synthetic 15w-40 in diesels...watcha think? - Defender Source
Defender Source  

Go Back   Defender Source > Defender & Series Technical Discussions > Defender Technical Discussions


Reply
 
Thread Tools
  #1  
Old March 31st, 2008, 01:39 PM
D90user's Avatar
D90user
Status: Offline
steve
109/110 ambulance-55 series I
Member
 
Join Date: Oct 2004
Location: Nevada
Posts: 1,447
synthetic 15w-40 in diesels...watcha think?

Hey All,
I have been running Rotella 15w40 in the 300tdi but I'm considering switching to amsoil 15w40.

comments/suggestions?
I just did the oil pan and I dont have a sludge problem, just looking to extend life and possibly drain interval... how long can you leave synthetic in for during heavy use?
Reply With Quote
Sponsored Links
Advertisement
 
  #2  
Old March 31st, 2008, 04:12 PM
Overlander's Avatar
Overlander
Status: Offline
mark kellgren
in between D's in an 04 D2
Member
 
Join Date: Mar 2006
Location: Charlotte, NC
Posts: 6,531
Registry
good question. now that my engine is broke in, I switched to Mobil 1 turbo diesel.
Reply With Quote
  #3  
Old March 31st, 2008, 04:31 PM
Red90's Avatar
Red90
Status: Online
John B.
1991 Defender 90, 200TDI
Site Team
 
Join Date: Sep 2003
Location: Calgary
Posts: 9,232
Registry
Only use 15W-40 if you live somewhere that does not get too cold.

As to how long a drain interval.... Normally diesel engine oil change intervals are governed by soot levels. It should be changed before the soot reaches 1%. The only way to tell is through oil analysis as it will vary by engine. Any decent synthetic diesel engine oil will last many times longer than the time it takes to achieve these soot levels.
Reply With Quote
Sponsored Links
Advertisement
 
  #4  
Old March 31st, 2008, 04:35 PM
D90user's Avatar
D90user
Status: Offline
steve
109/110 ambulance-55 series I
Member
 
Join Date: Oct 2004
Location: Nevada
Posts: 1,447
Quote:
Originally Posted by Overlander
good question. now that my engine is broke in, I switched to Mobil 1 turbo diesel.
is that 5w40??probably good for you fresh motor... but for a older tdi I don't think I go that thin (Am I worng on this?).
FYI- Amsoil makes a HD 5w40 also

Follow-up Post:

Quote:
Originally Posted by Red90
Only use 15W-40 if you live somewhere that does not get too cold.

As to how long a drain interval.... Normally diesel engine oil change intervals are governed by soot levels. It should be changed before the soot reaches 1%. The only way to tell is through oil analysis as it will vary by engine. Any decent synthetic diesel engine oil will last many times longer than the time it takes to achieve these soot levels.
What is too cold?
Have you done an oil anlaysis on yours? What did you find?

Cheers
Reply With Quote
  #5  
Old March 31st, 2008, 04:43 PM
Red90's Avatar
Red90
Status: Online
John B.
1991 Defender 90, 200TDI
Site Team
 
Join Date: Sep 2003
Location: Calgary
Posts: 9,232
Registry
The SAE cranking test is -20 C for a 15W oil. I would suggest not cold starting below -10 C ever.

On my 200TDI, I had 0.2% soot at 6500 km, which is my only test to date. Assuming you think everything is OK and you are not heavily modified, 10000 km for your first change and analysis should be very safe.

Follow-up Post:

Quote:
Originally Posted by D90user
is that 5w40??probably good for you fresh motor... but for a older tdi I don't think I go that thin (Am I worng on this?).
FYI- Amsoil makes a HD 5w40 also
5W40 is NOT thinner than 15W-40 once the engine is at running temperature. The first number is the indication of cold temperature viscosity and the second is the running temperature viscosity. All XW-40 oils should have similar viscosity in a running engine.
Reply With Quote
  #6  
Old March 31st, 2008, 04:55 PM
D90user's Avatar
D90user
Status: Offline
steve
109/110 ambulance-55 series I
Member
 
Join Date: Oct 2004
Location: Nevada
Posts: 1,447
thanks for the info. My engine is not modified much. Looking to save time/$ in the short and long run.

http://www.defendersource.com/forum/...ght=diesel+oil

Found this to be interesting.... but 1w40 diesel oil is not easy to come by.

What would be my benifit to switching to 5w-40 synthetic like the rotella synthetic? -10C will not happen often for me. But I will be driving to South America so avalibility is an issue.

Is all this a moot point and I should just stick with 15w40 dino and change often?

cheers
Reply With Quote
  #7  
Old March 31st, 2008, 06:39 PM
Red90's Avatar
Red90
Status: Online
John B.
1991 Defender 90, 200TDI
Site Team
 
Join Date: Sep 2003
Location: Calgary
Posts: 9,232
Registry
There are benefit to a quality oil in engine life, but the differences may mean rebuilds at 500000 miles instead of 1000000........ Changing it before it becomes too dirty or degrades is the biggest thing. However multi million miles between rebuilds are possible with the proper oil, good maintenance and proper use of oil analysis. Quality modern oils can get you to very low wear values.

I don't think that there is any benefit to 5W-40 over 15W-40 if you are in a warm climate. There probably is a slight benefit, but I have not see any analysis to show the differences. You should be able to get 5W-40 synthetic in the USA for $20 a gallon, so, personally, I can't see the reason to use 15W-40 dino oil n a smal engine such as this.

Shell Rotella 5W-40, Petro-Canada Duron XL 5W-40 or Mobil 1 Turbo Diesel Truck 5W-40 should all be easy to find and not very expensive. 0W-40 diesel engine oils are common in Canada, but I don't think they are in the US.

If you care (which you seem to) it really does make sense to get an oil analysis done every change. They cost little and will tell you if the oil is working in YOUR engine and can also point out other problems that you may not know about. Things like intake leaks are easy to see from an analysis.
Reply With Quote
  #8  
Old April 1st, 2008, 07:24 AM
Lee
Status: Offline
Lee O
95 NAS D-90 300Tdi
Member
 
Join Date: Jun 2007
Location: Wilton, NH
Posts: 43
Why wouldn't you start below -10C (~14F)? What do you do if it's below that temp?
Reply With Quote
  #9  
Old April 1st, 2008, 02:48 PM
Red90's Avatar
Red90
Status: Online
John B.
1991 Defender 90, 200TDI
Site Team
 
Join Date: Sep 2003
Location: Calgary
Posts: 9,232
Registry
Quote:
Originally Posted by Lee
Why wouldn't you start below -10C (~14F)? What do you do if it's below that temp?
15W-40 is too thick and will not pump quickly enough to prevent cold start damage. You should be using a different oil if you need to cold start below those temperature.
Reply With Quote
  #10  
Old April 1st, 2008, 03:40 PM
Lee
Status: Offline
Lee O
95 NAS D-90 300Tdi
Member
 
Join Date: Jun 2007
Location: Wilton, NH
Posts: 43
I'm using 5W-40. Your comment about never below -10C seemed to be regardless of the weight.

-Lee
Reply With Quote
  #11  
Old April 1st, 2008, 05:26 PM
Red90's Avatar
Red90
Status: Online
John B.
1991 Defender 90, 200TDI
Site Team
 
Join Date: Sep 2003
Location: Calgary
Posts: 9,232
Registry
Quote:
Originally Posted by Lee
I'm using 5W-40. Your comment about never below -10C seemed to be regardless of the weight.
If you say so. That is not how I intended it.

Quote:
Originally Posted by Red90
The SAE cranking test is -20 C for a 15W oil. I would suggest not cold starting below -10 C ever.
The test for a 5W oil is -30 C..... So I would suggest not cold starting below -20C.......
Reply With Quote
Reply

Lower Navigation
Go Back   Defender Source > Defender & Series Technical Discussions > Defender Technical Discussions

Tags
diesel

Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
V8 Engine Oil - Synthetic vs Semi Synthetic nickt Defender Technical Discussions 68 September 18th, 2016 09:38 AM
Synthetic or Dino, What do you use??? javelinadave Defender Technical Discussions 16 February 8th, 2005 07:33 PM
Dynaflex Synthetic Winch Lines Starting @ $280.00 RedRhinoProducts The Vendors Loft 1 November 4th, 2004 09:07 AM
Oil Info XD90 Defender Technical Discussions 5 September 7th, 2004 10:07 PM
Which synthetic rope revisited: snuffer Defender Technical Discussions 0 June 14th, 2004 07:59 PM


All times are GMT -5. The time now is 12:19 PM.


Copyright