saw this thought you guys might find it as usefull as i did
Oils and Lubricants for your Defender, Range Rover or Discovery
At the kind request of an LRO Forum Moderator here is a guide to selecting lubricants for your favourite 4x4. It is not intended as a criticism of anyone’s particular lubricant usage but simply to give you more information when making the choices that suit you best. It is NOT brand or SUPPLIER specific either, the SAE viscosity grades and API or ACEA application grades are International Standards that are used by ALL lubricant manufacturers.
With so many variants of engine and gearbox, it’s easy to get confused when deciding just what lubricant will ensure your favourite 4x4 gives a long and trouble-free life.
Although selecting the wrong lubricant doesn’t usually result in catastrophic failure (unless you get it REALLY wrong) it does more often than not:
Reduce performance
Reduce economy
Increase oil consumption
Accelerate wear
Give baulky gear changes (in the case of gear oils)
Many folks have found the ideal lubricant for their engines through careful research, manufacturers’ recommendations or trial and error. However, for those who don’t have easy access to the right information, or who are confused by what the various grades and specifications mean, here is a guide to selecting the right lubricants for your Land Rover vehicle.
Engines
4 Cylinder Petrol and Diesel (Naturally Aspirated) 2286 & 2495cc (Land Rover 90 & 110)
These engines are very, very robust but also dated by modern standards. Consequently, the design, running tolerances and typical operating conditions of these engines do not demand ultra low viscosity synthetic oils, which are predominantly too thin. Additionally, you MUST NOT use a latest generation, highly additive treated oil with these engines since this can sometimes give rise to bore glazing and damaging bore wear.
Therefore a 15W50 multigrade plain mineral oil is ideal and, being a higher viscosity, its thicker film will make up for its lack of film strength compared to low viscosity synthetics.
By adopting a viscosity span of SAE 15W/50, slightly improved fuel economy and cold starting is achieved as a result of lower frictional losses compared with using conventional SAE 20W/50 grades but SAE20W50 can be used too of course.
Land Rover’s original recommended quality grade of API SF/CD is somewhat dated now. Hence you should look for quality grades of API SG/CE or ACEA A2-96/B2-96. Do not exceed these grades for the reasons mentioned earlier.
Equally, good quality 15W50 is getting harder to find nowadays (beware very cheap brands which are sold for keeping old bangers on the road at the barest minimum cost) so you may need to mail order it from specialists like us.
However, you can substitute a 15W40 viscosity grade if your engine is in very good condition and is not suffering from high oil consumption. 15W40 still dominates many trucking fleets so good quality brands shouldn’t be hard to find. Again grades API SG/CE or ACEA A2-96/B2-96 are more than adequate.
If you experience smoking or higher oil consumption with a 15W40 oil then switch back to a 15W50 grade.
If you are working these engines very, very hard then we recommend a service interval of no more than 3,000 miles, however a 6,000 mile interval will suffice for most.
Note modern lubricants are compatible with BOTH petrol and diesel engines if the correct grades are selected.
4 Cylinder Turbo Diesel - 19J Falcon 2495cc (Land Rover 90 & 110)
This engine was introduced BEFORE the later 200TDI and has, rightly or wrongly, suffered a mixed reputation for reliability. It is essentially a derivative of its naturally aspirated predecessor so owes much of its engineering to that venerable old design. However, the higher performance and temperatures of this engine means it can use lubricants with higher additive levels without the danger of bore glazing.
The addition of a non-intercooled Turbo has perhaps pushed the engine close to its design limits and consequently it does not favour being worked hard at high RPMs for prolonged periods (i.e. thrashing up and down motorways). Nonetheless, many happy owners have enjoyed long service from this engine but be warned, neglect its servicing at your peril and drive it conservatively.
The Turbo needs a rapid feed of oil first thing since it spins at many thousands of RPM (don’t rev your Turbo engine when you start it, wait a minute or two for the oil to circulate, allow time too for the turbo to slow down before turning off your engine). Hence the oil needs to flow rapidly from start up, especially on cold winter mornings. Therefore we recommend a 15W40 viscosity grade, but this time look for really severe duty, long drain grades of API SJ/CH-4 or ACEA B3, E3 specification. These will ensure that the lubricant can cope with thermal and mechanical stresses of this particular engine as well as the combustion by-products that build up in the oil (the Falcon engine isn’t a particularly clean burning engine compared to its later cousins).
15W40 is available in both plain mineral and semi synthetic formulation, however a plain mineral grade is more than adequate IF it meets the quality grades above.
It is also possible to use a 10W40 viscosity grade (a very, very common viscosity nowadays) however this may produce a smoky start up until the engine warms up due to its lower viscosity. If you experience smoking or higher oil consumption with a 10W40 oil then switch back to a 15W40 grade.
4 Cylinder Turbo Diesel – VM engine 2393 & 2500cc (Range Rover)
In common with Land Rover’s own early Turbo Diesel (the 19J Falcon), these Italian engines fitted to Range Rovers also enjoyed a mixed reputation for reliability. Being of a similar generation it’s probably no surprise to learn that these engines have identical lubricant requirements to the 19J Falcon engine.
Therefore we recommend a 15W40 viscosity grade and again look for really severe duty, long drain grades of API SJ/CH-4 or ACEA B3, E3 specification. This will ensure that the lubricant can cope with thermal and mechanical stresses of these particular engines as well as the combustion by-products that build up in the oil (the VM engine isn’t a particularly clean burning engine compared to more modern Diesels).
200TDI & 300TDI Diesel (Land Rover 90 & 110, Discovery, Range Rover)
Moving on from the 19J Turbo engine we come to Land Rover’s legendary TDI, in both early 200TDI and later 300TDI guise. The TDI engines were a significant step forward for Land Rover since these engines give good economy and reasonable Torque. Although both engines have minor design flaws, these are easily addressed and with the right lubricant a TDI will run at least twice round the clock without difficulty.
Because of their affordable versatility, TDIs find themselves doing everything from long Motorway hauls to (dare I say it) school runs, and so they need a really versatile lubricant to cover all these conditions.
Consequently, we recommend a 10W40 viscosity grade with a high synthetic content that meets API grade SL/CF or ACEA grade A3/B3. This will give good economy but still cope with the most severe demands likely to be placed on the engine, even if it has been performance enhanced (which often increases the combustion by-products building up in the oil, something an ACEA A3/B3 grade can take in its stride).
Once again though, if you have a ‘tired’ engine that is smoky as a result of highish oil consumption, you should switch to a 15W40 viscosity grade as used by the 19J Falcon engine (API SJ/CH-4 or ACEA B3, E3), since its thicker viscosity will reduce oil consumption, especially from start up.
TD5 5 Cylinder Turbo Diesel (Land Rover 90 & 110, Discovery)
Now we come to the most modern of the diesel engines in the current fleet, the TD5. In one sense the TD5 is kinder to its lubricant by virtue of its cleaner burning design and superior filtration. It should therefore produce less particulates and combustion by-products than, say, a TDI. Equally, this engine truly does owe its design and development to the latest generation of higher performance, clean burning, electronically managed diesel engines and consequently it is ideally suited to the latest generation of low viscosity lubricants.
For engines in standard tune, you should select an oil with a viscosity of 5W30 that meets or exceeds ACEA specification A1/B1. Such oil will either be high (at least 50% synthetic) or fully synthetic and will give the best combination of protection and ECONOMY in the TD5.
However, many of you will have performance enhanced TD5s (i.e. superchipped or power boosted) and performance enhanced engines often run at higher temperatures than those in standard tune (if you are working them hard).
Consequently, performance enhanced TD5’s need a lubricant with an upper viscosity span that has the staying power to protect and lubricate even in the most critical areas of thermal stress and extreme load. Hence for such engines you should use a 5W40 viscosity grade that meets ACEA specification B3 or B5. Note the penalty for this is a slight lessening of economy but if you’ve power boosted your engine, economy probably isn’t your overriding consideration.
V8 Petrol – Carburetor and EFI (Land Rover 90 & 110, Discovery, Range Rover)
Lastly we come to the venerable but cherished V8 petrol power plant. As many of you will know, this engine has been around in various guises since the sixties and consequently it’s not too demanding of its engine oil (in terms of thermal and mechanical stress) despite its reputation for longevity.
However, because it is based on a very old design it likes a relatively viscous oil to give a good amount of oil pressure, especially in the upper engine and hydraulic tappets. Equally, the running tolerances and temperatures on older engines (eg carburetor variants) do not favour highly additive treated lubricants which can give rise to bore glazing.
Hence for older Land Rover V8's (all carburetor versions) a good quality 15W50 viscosity grade mineral oil is perfectly suited. By adopting a viscosity span of SAE 15W/50, slightly improved fuel economy and cold starting is achieved as a result of lower frictional losses compared with using conventional SAE 20W/50 grades grades but SAE20W50 can be used too of course.
With Land Rover's V8 engines, what really matters is the cleanliness of the oil since V8's have a tendency to pollute it with combustion by-products (via leaking head gaskets) and this leads to heavy, constricting deposits and tar like gums within the engine.
Therefore for best results you should opt for an oil with good detergency. A diesel compatible oil is ideal for these very reasons. Therefore you should look for an oil that meets quality grades API SG/CE or ACEA A2, B2.
Note though that if the engine has been neglected or is tired and already has heavy deposits of sludge, then a very highly detergent oil may dislodge deposits that subsequently block oil ways, increase leakage or increase running tolerances so don't use a very highly specified, so-called 'diesel specific' oil.
Candidly, if the engine is anything darker than honey brown under the rocker covers then it may need some TLC in the workshop if you want best results from it. Conversely, it will probably soldier on for a very long time in a worn state but with lower performance and economy.
You should, however, change the engine oil regularly at no more than 6,000 mile intervals WITHOUT FAIL and many enthusiasts change the oil at 3,000 miles.
If you have a later EFI V8 (Fuel injected), then these engines (in good condition) are capable of running on a lower 10W40 viscosity grade. This gives better economy, especially for EFI engines that are soaking up higher mileages on fast roads such as motorways. You can opt for high or fully synthetic oils of this viscosity range but do bear in mind the aforementioned effects of a highly additive treated oil (say ACEA grade A3/B3) on an engine that has significant tar like deposits within, or that is not running at those higher temperatures borne of sustained high speeds. Only opt for 10W40 grade if your EFI engine is in good condition and is being worked hard at higher road speeds.
If you are racing your V8, then you have quite a few choices to make since you may wish to sacrifice the ultimate longevity of the engine in return for greater power output. If you want the lowest viscosity, then you might opt for a 10W30 grade but this is on the very limit of the viscosity that the V8 will accept even in race tuned condition. For racing engines, we recommend nothing thinner than a 10W40 viscosity span which should be fully synthetic.
If you are really, really squeezing the power out of the engine (perhaps with NOS), then we recommend you look for a specialist 20W50 fully synthetic racing oil (popular in the US amongst V8 racers) since this will have the film strength to cope with the extremes of stress and temperature imposed at the very highest limits of the V8’s power capability.
Gearboxes
Having covered engines, we can now consider transmissions.
5-speed LT77 and R380 main gearbox (Land Rover 90 & 110, Discovery, Range Rover)
Firstly, let’s deal with the somewhat notorious LT77 and R380 5-speed main gearbox. These are famed for a poor, notchy gear change, especially from 1st to 2nd gear.
The notchy gear change is due to a combination of a weak synchromesh and the use of a plain mineral ATF fluid.
ATF was originally specified for the LT77 5-speed gearbox and, theoretically, could be used in the later R380 box. Type DIII is the best grade currently available. ATF was originally specified because of the weak synchromesh in the LT77 and R380 boxes (especially second gear).
ATF has a very low viscosity (rated as 5W20 since it falls below normal gear oil viscosity grades) and so it has minimal drag on the gears, enabling the weak synchromesh to do the best of a bad job.
BUT ATF has several drawbacks which is why it is NO LONGER recommended for use in such boxes. These are:
It is generally a plain mineral base stock formulation (even DIII) and this, coupled to its very low viscosity, means that it is poor at preventing metal to metal wear in manual transmissions.
This is compounded by the fact that the viscosity improvers within (thickeners) are more rapidly sheared down in manual transmissions. Again, this reduces the protective film strength of the ATF in those areas of high pressure contact and also increases transmission noise.
ATF thickens as temperatures drop (increasing that drag on the gears) which is why folks notice that gear changes are worst on cold mornings and improve after a few miles motoring when the ATF has warmed up a little.
So, what are the alternatives?
Land Rover currently has commercial arrangement with Texaco/Chevron that leads it to recommend a Texaco/Chevron MTF94 fluid. From the freeback we have received and read on this Forum and elsewhere, we feel it’s a little too viscous (5W30 or 70W80) to give the best results. Nonetheless you should use it in preference to ATF if your choice is limited to the two.
However, there are better alternatives such as the fully synthetic MT75D gear oil we have developed. Rather than simply plug our MT75D I’ll give pointers to what you should look for when seeking alternatives to ATF or MTF94.
Firstly, the lubricant must have the original 5W20 low viscosity of ATF fluids to give minimum gear drag. However, it MUST also be formulated only from fully synthetic base stocks since these will have a much higher lubricant film strength so as not to be squeezed out of those all important high pressure contact areas where wear might occur. This, and the low viscosity, has the added benefit of reducing friction which lowers transmission noise and improves economy.
It must also be highly shear stable and able to maintain its optimum working viscosity over a very wide temperature range. This and a very, very carefully matched coefficient of friction (probably the most critical parameter) will ensure that it dramatically improves gear shifting in LT77 and R380 boxes (especially from cold).
It is the improved shear stability and higher film strength that enables synthetic gear lubricants to outlast their plain mineral counterparts by up to 5 times. However, we err very much on the cautious side and recommend only a doubling of drain intervals.
Note that unlike engine oils, gear oils do not have combustion by-products building up in them, nor do they suffer the higher temperatures of engines, so extending drain intervals is entirely acceptable if the lubricant is of the highest performance and the increase is modest. The exception to this would be if the gear oil were contaminated, perhaps by water or mud during deep wading, though this is unlikely. If the oil is contaminated in this way it MUST be changed immediately, regardless of its formulation.
LT230 Transfer Box (Land Rover 90 & 110, Discovery, Range Rover)
That’s the problems of the LT77 and R380 boxes solved, but what about the LT230 transfer box to which these are commonly mated?
You should NOT use ATF, MTF94 or MT75D in an LT230 TRANSFER box. It must use a thicker gear oil such as EP90 (monograde), EP80W90 (multigrade which is better for cold starting lubrication on winter mornings) or EP75W90 (typically fully synthetic giving the best lubrication of all). This is the same lubricant that you should use in your axles and you should look for an API GL5 specification for best protection.
Borg Warner Chain Drive Transfer Box (Range Rover)
The only transfer box from Land Rover where ATF was originally recommended is the BORG WARNER chain drive box as fitted to Range Rover vehicles from around 1989 onwards. Again, type DIII is the best grade currently available but guess what, these Borg Warner boxes suffer from wear around the chain and sprockets!! Another application for a fully synthetic MT75D type solution, we feel.
LT95 & LT85 (Land Rover 90 & 110, Range Rover)
Very early 90 and 110’s were fitted with either LT95 4-speed (also fitted to early Classic Range Rovers) or LT85 5-speed gearboxes.
These boxes are very robust and when mated to engines in standard tune are relatively unstressed. Consequently, both boxes can be filled with a 15W50 or 20W50 engine oil (API SG/CE or ACEA A2-96/B2-96).
If you choose to use engine oil in your LT95 or LT85 gearbox, we very strongly recommend that you change the oil in the box at the SAME time as you change your engine oil (i.e. no more than 6,000 miles). This is because in manual gearboxes, engine oil provides limited extreme pressure protection and the viscosity improvers within it tend to shear down faster, again reducing protection since the lubricating film thins out.
If you want better protection for these boxes you should opt for 75W90 Fully Synthetic Gear Oil to API GL5 specification.
Be careful though since, generally speaking, GL5 oils are incompatible with the copper alloys found in older generation gearboxes. Certain additives within can cause leaching of the copper and this weakens the component, especially the synchro rings. You should check with your supplier that any GL5 Fully Synthetic Oil you use is FULLY compatible with copper and its alloys and suitable for use in older transmissions.
ZF HP22 4-speed Automatic Gearbox (Land Rover 90 & 110, Discovery, Range Rover)
That’s manual gearboxes covered, but many late vehicles are fitted with the ZF HP22 4-speed automatic box.
In reality, the ZF 4-speed auto box fitted to these vehicles is more than happy with Non Synthetic ATF fluids, and the latest ATF DIII grade is the one to use since it is better suited to the small orifices and electronic control systems in the latest generation of auto boxes. Regular fluid and filter changes will see the box give a very, very long life without the need for Synthetics.
However, if you live in hotter climes, or if the box is being worked extremely hard (say touring the Alps in Summer!), then a Synthetic fluid will significantly reduce the transmission temperature and this is worth the expense alone to avoid an overheated transmission.
So, if you want the best fluid for your ZF auto box then synthetic is the way to go for maximum box life, best economy (such as it is with an auto box!) and lowest transmission temperature. If you want the VERY best fluid then you won’t do better than an MT75D type fluid since it is perfect for ZF 4-speed auto boxes.
Chrysler Torqueflite 3-speed Automatic Gearbox (Range Rover)
Reputedly, this 3-speed auto box offered prior to the ZF 4-speed was about as ‘bullet proof’ as auto boxes could get. It’s a very tough, very simple, long lived unit and runs happily on ATF Type DII or as mentioned earlier, the latest ATF Type DIII type fluid.
Note that not all older generation auto boxes can run on ATF DII or DIII, but the Torqueflite unit factory fitted to Classic Range Rovers is fine with either.
Further Info
I hope you find the information above useful.
Don’t forget too that you can find some FREE and detailed features on renewing gearbox oils and servicing your favourite 4x4 in our online technical library:
Difflock Servicing Guides
You can also find some free and detailed guides to selecting engine oils on our website here:
Difflock Guide to Oils & Lubricants – Background Info
Difflock Guide to Oils & Lubricants – Selecting the best oil for your engine
Feel free to email me at: info@difflock.com if you have any specific lubricant queries you would like me to answer.
One last note, some of you folks may wish to copy all or some of this info to your club website or similar. By all means feel free to do this but DO please acknowledge www.difflock.com as the source of the info, since without visitors (and hopefully customers) on our website we can’t survive and continue to provide the free resources that many of you find helpful.
Best regards
Peter
http://www.difflock.com
Follow-up Post:
by the way
i am in no way affiliated with Difflock or thier site just saw that info on another forum and thought it might be useful to those who havent seen it but dont want ya'll thinking im plugging my own site
James
Oils and Lubricants for your Defender, Range Rover or Discovery
At the kind request of an LRO Forum Moderator here is a guide to selecting lubricants for your favourite 4x4. It is not intended as a criticism of anyone’s particular lubricant usage but simply to give you more information when making the choices that suit you best. It is NOT brand or SUPPLIER specific either, the SAE viscosity grades and API or ACEA application grades are International Standards that are used by ALL lubricant manufacturers.
With so many variants of engine and gearbox, it’s easy to get confused when deciding just what lubricant will ensure your favourite 4x4 gives a long and trouble-free life.
Although selecting the wrong lubricant doesn’t usually result in catastrophic failure (unless you get it REALLY wrong) it does more often than not:
Reduce performance
Reduce economy
Increase oil consumption
Accelerate wear
Give baulky gear changes (in the case of gear oils)
Many folks have found the ideal lubricant for their engines through careful research, manufacturers’ recommendations or trial and error. However, for those who don’t have easy access to the right information, or who are confused by what the various grades and specifications mean, here is a guide to selecting the right lubricants for your Land Rover vehicle.
Engines
4 Cylinder Petrol and Diesel (Naturally Aspirated) 2286 & 2495cc (Land Rover 90 & 110)
These engines are very, very robust but also dated by modern standards. Consequently, the design, running tolerances and typical operating conditions of these engines do not demand ultra low viscosity synthetic oils, which are predominantly too thin. Additionally, you MUST NOT use a latest generation, highly additive treated oil with these engines since this can sometimes give rise to bore glazing and damaging bore wear.
Therefore a 15W50 multigrade plain mineral oil is ideal and, being a higher viscosity, its thicker film will make up for its lack of film strength compared to low viscosity synthetics.
By adopting a viscosity span of SAE 15W/50, slightly improved fuel economy and cold starting is achieved as a result of lower frictional losses compared with using conventional SAE 20W/50 grades but SAE20W50 can be used too of course.
Land Rover’s original recommended quality grade of API SF/CD is somewhat dated now. Hence you should look for quality grades of API SG/CE or ACEA A2-96/B2-96. Do not exceed these grades for the reasons mentioned earlier.
Equally, good quality 15W50 is getting harder to find nowadays (beware very cheap brands which are sold for keeping old bangers on the road at the barest minimum cost) so you may need to mail order it from specialists like us.
However, you can substitute a 15W40 viscosity grade if your engine is in very good condition and is not suffering from high oil consumption. 15W40 still dominates many trucking fleets so good quality brands shouldn’t be hard to find. Again grades API SG/CE or ACEA A2-96/B2-96 are more than adequate.
If you experience smoking or higher oil consumption with a 15W40 oil then switch back to a 15W50 grade.
If you are working these engines very, very hard then we recommend a service interval of no more than 3,000 miles, however a 6,000 mile interval will suffice for most.
Note modern lubricants are compatible with BOTH petrol and diesel engines if the correct grades are selected.
4 Cylinder Turbo Diesel - 19J Falcon 2495cc (Land Rover 90 & 110)
This engine was introduced BEFORE the later 200TDI and has, rightly or wrongly, suffered a mixed reputation for reliability. It is essentially a derivative of its naturally aspirated predecessor so owes much of its engineering to that venerable old design. However, the higher performance and temperatures of this engine means it can use lubricants with higher additive levels without the danger of bore glazing.
The addition of a non-intercooled Turbo has perhaps pushed the engine close to its design limits and consequently it does not favour being worked hard at high RPMs for prolonged periods (i.e. thrashing up and down motorways). Nonetheless, many happy owners have enjoyed long service from this engine but be warned, neglect its servicing at your peril and drive it conservatively.
The Turbo needs a rapid feed of oil first thing since it spins at many thousands of RPM (don’t rev your Turbo engine when you start it, wait a minute or two for the oil to circulate, allow time too for the turbo to slow down before turning off your engine). Hence the oil needs to flow rapidly from start up, especially on cold winter mornings. Therefore we recommend a 15W40 viscosity grade, but this time look for really severe duty, long drain grades of API SJ/CH-4 or ACEA B3, E3 specification. These will ensure that the lubricant can cope with thermal and mechanical stresses of this particular engine as well as the combustion by-products that build up in the oil (the Falcon engine isn’t a particularly clean burning engine compared to its later cousins).
15W40 is available in both plain mineral and semi synthetic formulation, however a plain mineral grade is more than adequate IF it meets the quality grades above.
It is also possible to use a 10W40 viscosity grade (a very, very common viscosity nowadays) however this may produce a smoky start up until the engine warms up due to its lower viscosity. If you experience smoking or higher oil consumption with a 10W40 oil then switch back to a 15W40 grade.
4 Cylinder Turbo Diesel – VM engine 2393 & 2500cc (Range Rover)
In common with Land Rover’s own early Turbo Diesel (the 19J Falcon), these Italian engines fitted to Range Rovers also enjoyed a mixed reputation for reliability. Being of a similar generation it’s probably no surprise to learn that these engines have identical lubricant requirements to the 19J Falcon engine.
Therefore we recommend a 15W40 viscosity grade and again look for really severe duty, long drain grades of API SJ/CH-4 or ACEA B3, E3 specification. This will ensure that the lubricant can cope with thermal and mechanical stresses of these particular engines as well as the combustion by-products that build up in the oil (the VM engine isn’t a particularly clean burning engine compared to more modern Diesels).
200TDI & 300TDI Diesel (Land Rover 90 & 110, Discovery, Range Rover)
Moving on from the 19J Turbo engine we come to Land Rover’s legendary TDI, in both early 200TDI and later 300TDI guise. The TDI engines were a significant step forward for Land Rover since these engines give good economy and reasonable Torque. Although both engines have minor design flaws, these are easily addressed and with the right lubricant a TDI will run at least twice round the clock without difficulty.
Because of their affordable versatility, TDIs find themselves doing everything from long Motorway hauls to (dare I say it) school runs, and so they need a really versatile lubricant to cover all these conditions.
Consequently, we recommend a 10W40 viscosity grade with a high synthetic content that meets API grade SL/CF or ACEA grade A3/B3. This will give good economy but still cope with the most severe demands likely to be placed on the engine, even if it has been performance enhanced (which often increases the combustion by-products building up in the oil, something an ACEA A3/B3 grade can take in its stride).
Once again though, if you have a ‘tired’ engine that is smoky as a result of highish oil consumption, you should switch to a 15W40 viscosity grade as used by the 19J Falcon engine (API SJ/CH-4 or ACEA B3, E3), since its thicker viscosity will reduce oil consumption, especially from start up.
TD5 5 Cylinder Turbo Diesel (Land Rover 90 & 110, Discovery)
Now we come to the most modern of the diesel engines in the current fleet, the TD5. In one sense the TD5 is kinder to its lubricant by virtue of its cleaner burning design and superior filtration. It should therefore produce less particulates and combustion by-products than, say, a TDI. Equally, this engine truly does owe its design and development to the latest generation of higher performance, clean burning, electronically managed diesel engines and consequently it is ideally suited to the latest generation of low viscosity lubricants.
For engines in standard tune, you should select an oil with a viscosity of 5W30 that meets or exceeds ACEA specification A1/B1. Such oil will either be high (at least 50% synthetic) or fully synthetic and will give the best combination of protection and ECONOMY in the TD5.
However, many of you will have performance enhanced TD5s (i.e. superchipped or power boosted) and performance enhanced engines often run at higher temperatures than those in standard tune (if you are working them hard).
Consequently, performance enhanced TD5’s need a lubricant with an upper viscosity span that has the staying power to protect and lubricate even in the most critical areas of thermal stress and extreme load. Hence for such engines you should use a 5W40 viscosity grade that meets ACEA specification B3 or B5. Note the penalty for this is a slight lessening of economy but if you’ve power boosted your engine, economy probably isn’t your overriding consideration.
V8 Petrol – Carburetor and EFI (Land Rover 90 & 110, Discovery, Range Rover)
Lastly we come to the venerable but cherished V8 petrol power plant. As many of you will know, this engine has been around in various guises since the sixties and consequently it’s not too demanding of its engine oil (in terms of thermal and mechanical stress) despite its reputation for longevity.
However, because it is based on a very old design it likes a relatively viscous oil to give a good amount of oil pressure, especially in the upper engine and hydraulic tappets. Equally, the running tolerances and temperatures on older engines (eg carburetor variants) do not favour highly additive treated lubricants which can give rise to bore glazing.
Hence for older Land Rover V8's (all carburetor versions) a good quality 15W50 viscosity grade mineral oil is perfectly suited. By adopting a viscosity span of SAE 15W/50, slightly improved fuel economy and cold starting is achieved as a result of lower frictional losses compared with using conventional SAE 20W/50 grades grades but SAE20W50 can be used too of course.
With Land Rover's V8 engines, what really matters is the cleanliness of the oil since V8's have a tendency to pollute it with combustion by-products (via leaking head gaskets) and this leads to heavy, constricting deposits and tar like gums within the engine.
Therefore for best results you should opt for an oil with good detergency. A diesel compatible oil is ideal for these very reasons. Therefore you should look for an oil that meets quality grades API SG/CE or ACEA A2, B2.
Note though that if the engine has been neglected or is tired and already has heavy deposits of sludge, then a very highly detergent oil may dislodge deposits that subsequently block oil ways, increase leakage or increase running tolerances so don't use a very highly specified, so-called 'diesel specific' oil.
Candidly, if the engine is anything darker than honey brown under the rocker covers then it may need some TLC in the workshop if you want best results from it. Conversely, it will probably soldier on for a very long time in a worn state but with lower performance and economy.
You should, however, change the engine oil regularly at no more than 6,000 mile intervals WITHOUT FAIL and many enthusiasts change the oil at 3,000 miles.
If you have a later EFI V8 (Fuel injected), then these engines (in good condition) are capable of running on a lower 10W40 viscosity grade. This gives better economy, especially for EFI engines that are soaking up higher mileages on fast roads such as motorways. You can opt for high or fully synthetic oils of this viscosity range but do bear in mind the aforementioned effects of a highly additive treated oil (say ACEA grade A3/B3) on an engine that has significant tar like deposits within, or that is not running at those higher temperatures borne of sustained high speeds. Only opt for 10W40 grade if your EFI engine is in good condition and is being worked hard at higher road speeds.
If you are racing your V8, then you have quite a few choices to make since you may wish to sacrifice the ultimate longevity of the engine in return for greater power output. If you want the lowest viscosity, then you might opt for a 10W30 grade but this is on the very limit of the viscosity that the V8 will accept even in race tuned condition. For racing engines, we recommend nothing thinner than a 10W40 viscosity span which should be fully synthetic.
If you are really, really squeezing the power out of the engine (perhaps with NOS), then we recommend you look for a specialist 20W50 fully synthetic racing oil (popular in the US amongst V8 racers) since this will have the film strength to cope with the extremes of stress and temperature imposed at the very highest limits of the V8’s power capability.
Gearboxes
Having covered engines, we can now consider transmissions.
5-speed LT77 and R380 main gearbox (Land Rover 90 & 110, Discovery, Range Rover)
Firstly, let’s deal with the somewhat notorious LT77 and R380 5-speed main gearbox. These are famed for a poor, notchy gear change, especially from 1st to 2nd gear.
The notchy gear change is due to a combination of a weak synchromesh and the use of a plain mineral ATF fluid.
ATF was originally specified for the LT77 5-speed gearbox and, theoretically, could be used in the later R380 box. Type DIII is the best grade currently available. ATF was originally specified because of the weak synchromesh in the LT77 and R380 boxes (especially second gear).
ATF has a very low viscosity (rated as 5W20 since it falls below normal gear oil viscosity grades) and so it has minimal drag on the gears, enabling the weak synchromesh to do the best of a bad job.
BUT ATF has several drawbacks which is why it is NO LONGER recommended for use in such boxes. These are:
It is generally a plain mineral base stock formulation (even DIII) and this, coupled to its very low viscosity, means that it is poor at preventing metal to metal wear in manual transmissions.
This is compounded by the fact that the viscosity improvers within (thickeners) are more rapidly sheared down in manual transmissions. Again, this reduces the protective film strength of the ATF in those areas of high pressure contact and also increases transmission noise.
ATF thickens as temperatures drop (increasing that drag on the gears) which is why folks notice that gear changes are worst on cold mornings and improve after a few miles motoring when the ATF has warmed up a little.
So, what are the alternatives?
Land Rover currently has commercial arrangement with Texaco/Chevron that leads it to recommend a Texaco/Chevron MTF94 fluid. From the freeback we have received and read on this Forum and elsewhere, we feel it’s a little too viscous (5W30 or 70W80) to give the best results. Nonetheless you should use it in preference to ATF if your choice is limited to the two.
However, there are better alternatives such as the fully synthetic MT75D gear oil we have developed. Rather than simply plug our MT75D I’ll give pointers to what you should look for when seeking alternatives to ATF or MTF94.
Firstly, the lubricant must have the original 5W20 low viscosity of ATF fluids to give minimum gear drag. However, it MUST also be formulated only from fully synthetic base stocks since these will have a much higher lubricant film strength so as not to be squeezed out of those all important high pressure contact areas where wear might occur. This, and the low viscosity, has the added benefit of reducing friction which lowers transmission noise and improves economy.
It must also be highly shear stable and able to maintain its optimum working viscosity over a very wide temperature range. This and a very, very carefully matched coefficient of friction (probably the most critical parameter) will ensure that it dramatically improves gear shifting in LT77 and R380 boxes (especially from cold).
It is the improved shear stability and higher film strength that enables synthetic gear lubricants to outlast their plain mineral counterparts by up to 5 times. However, we err very much on the cautious side and recommend only a doubling of drain intervals.
Note that unlike engine oils, gear oils do not have combustion by-products building up in them, nor do they suffer the higher temperatures of engines, so extending drain intervals is entirely acceptable if the lubricant is of the highest performance and the increase is modest. The exception to this would be if the gear oil were contaminated, perhaps by water or mud during deep wading, though this is unlikely. If the oil is contaminated in this way it MUST be changed immediately, regardless of its formulation.
LT230 Transfer Box (Land Rover 90 & 110, Discovery, Range Rover)
That’s the problems of the LT77 and R380 boxes solved, but what about the LT230 transfer box to which these are commonly mated?
You should NOT use ATF, MTF94 or MT75D in an LT230 TRANSFER box. It must use a thicker gear oil such as EP90 (monograde), EP80W90 (multigrade which is better for cold starting lubrication on winter mornings) or EP75W90 (typically fully synthetic giving the best lubrication of all). This is the same lubricant that you should use in your axles and you should look for an API GL5 specification for best protection.
Borg Warner Chain Drive Transfer Box (Range Rover)
The only transfer box from Land Rover where ATF was originally recommended is the BORG WARNER chain drive box as fitted to Range Rover vehicles from around 1989 onwards. Again, type DIII is the best grade currently available but guess what, these Borg Warner boxes suffer from wear around the chain and sprockets!! Another application for a fully synthetic MT75D type solution, we feel.
LT95 & LT85 (Land Rover 90 & 110, Range Rover)
Very early 90 and 110’s were fitted with either LT95 4-speed (also fitted to early Classic Range Rovers) or LT85 5-speed gearboxes.
These boxes are very robust and when mated to engines in standard tune are relatively unstressed. Consequently, both boxes can be filled with a 15W50 or 20W50 engine oil (API SG/CE or ACEA A2-96/B2-96).
If you choose to use engine oil in your LT95 or LT85 gearbox, we very strongly recommend that you change the oil in the box at the SAME time as you change your engine oil (i.e. no more than 6,000 miles). This is because in manual gearboxes, engine oil provides limited extreme pressure protection and the viscosity improvers within it tend to shear down faster, again reducing protection since the lubricating film thins out.
If you want better protection for these boxes you should opt for 75W90 Fully Synthetic Gear Oil to API GL5 specification.
Be careful though since, generally speaking, GL5 oils are incompatible with the copper alloys found in older generation gearboxes. Certain additives within can cause leaching of the copper and this weakens the component, especially the synchro rings. You should check with your supplier that any GL5 Fully Synthetic Oil you use is FULLY compatible with copper and its alloys and suitable for use in older transmissions.
ZF HP22 4-speed Automatic Gearbox (Land Rover 90 & 110, Discovery, Range Rover)
That’s manual gearboxes covered, but many late vehicles are fitted with the ZF HP22 4-speed automatic box.
In reality, the ZF 4-speed auto box fitted to these vehicles is more than happy with Non Synthetic ATF fluids, and the latest ATF DIII grade is the one to use since it is better suited to the small orifices and electronic control systems in the latest generation of auto boxes. Regular fluid and filter changes will see the box give a very, very long life without the need for Synthetics.
However, if you live in hotter climes, or if the box is being worked extremely hard (say touring the Alps in Summer!), then a Synthetic fluid will significantly reduce the transmission temperature and this is worth the expense alone to avoid an overheated transmission.
So, if you want the best fluid for your ZF auto box then synthetic is the way to go for maximum box life, best economy (such as it is with an auto box!) and lowest transmission temperature. If you want the VERY best fluid then you won’t do better than an MT75D type fluid since it is perfect for ZF 4-speed auto boxes.
Chrysler Torqueflite 3-speed Automatic Gearbox (Range Rover)
Reputedly, this 3-speed auto box offered prior to the ZF 4-speed was about as ‘bullet proof’ as auto boxes could get. It’s a very tough, very simple, long lived unit and runs happily on ATF Type DII or as mentioned earlier, the latest ATF Type DIII type fluid.
Note that not all older generation auto boxes can run on ATF DII or DIII, but the Torqueflite unit factory fitted to Classic Range Rovers is fine with either.
Further Info
I hope you find the information above useful.
Don’t forget too that you can find some FREE and detailed features on renewing gearbox oils and servicing your favourite 4x4 in our online technical library:
Difflock Servicing Guides
You can also find some free and detailed guides to selecting engine oils on our website here:
Difflock Guide to Oils & Lubricants – Background Info
Difflock Guide to Oils & Lubricants – Selecting the best oil for your engine
Feel free to email me at: info@difflock.com if you have any specific lubricant queries you would like me to answer.
One last note, some of you folks may wish to copy all or some of this info to your club website or similar. By all means feel free to do this but DO please acknowledge www.difflock.com as the source of the info, since without visitors (and hopefully customers) on our website we can’t survive and continue to provide the free resources that many of you find helpful.
Best regards
Peter
http://www.difflock.com
Follow-up Post:
by the way
i am in no way affiliated with Difflock or thier site just saw that info on another forum and thought it might be useful to those who havent seen it but dont want ya'll thinking im plugging my own site
James
