I have a whining noise coming from the transfer case I believe. when i step on the gas in 3rd and 4th and 5th gear it builds with the RPMs climb. I let off the gas and it whines a bit as the truck lunges foward and stops as the wheel speed matches the tranny speed. Then I hit the gas again the whine comes back. I only really notive the noise in the higher gears.

Now I've looked this up on here and seems like the bearings could be going. I ordered bearing just incase. Could it be the mainshaft gear going? is that part number FTC5089?

Im going to drain the fluid and take off the cover and inspect tonight.

Im leaving for the National Rally Sept 14th and kind of need this solved by then. Anyone bringing a spare t-case I could buy if mine decides to die? Ron?

Hey Daniel,

Hate to be the bearer of bad news, but that sounds exactly like my 5-speed Discovery's symptoms before it was found to have eaten the splines off the output shaft of the transmission. Pull the PTO cover off the t-case asap, and inspect the splines on the output shaft/input gear for damage. If severe you can see the damage with a flashlight, without pulling the gear. I recommend you pull the input gear though to really know if this is the issue or not.

You are probably aware of this very common issue related to inadequate oil supply to the splines. Overfilling the T-Case a bit is helpful (since the area is splash lubricated, and the highest point in the t-case), but installing the updated crossdrilled gear seams to be the only long term fix (still a good idea to slightly overfill the t-case though).

 

1. Do you have adequate oil in the t-case and transmission? Are there shavings in the T-case or transmission fluid?
2. Pull the PTO cover and check spline wear.

Report back.

Ron

PS I do not have a spare case at the moment I wish to part with.

 

Mine whined for a long time before it blew up, but when it went, it went catastrophically and ate the trans too. Don't be a me.

 

Yours was seriously messed up though JimC. The poor yellow truck looked like the valdez with the amount of oil it leaked.

 

The fill plug will not come off so im going to a shop tonight to have them try to take it off with an air gun. I will then see if im low on oil when i drain it. Then I will take the cover off and inspect and take the PTO cover off and inspect there. if gears look ok then it might just be low on oil.

My friend has a spare lt230 out of a Disco. Its an auto I imagine. Do I need anything to adapt this? or can i bolt this straight on?

 

I"ve yet to find an airgun than can get to the fill plug.

 

"Do I need anything to adapt this? or can i bolt this straight on?"

You have to take the bulbous top plate off and remove the solinoid. May have to use your old speedo drive.

edit: this is assuming the t-case is out of a disco I.

 

So i took it to pepboys and they cracked the 1/2 fill plug for me. I brought it home and took the fill plug all the way out. no oil drippled out. so I started to undo the drain plug and snap! I broke the bolt! half of it is still in there, so i was lucky i guess. unbolted the cover instead to drain it and i was waiting for a surge of oil to go all over me. but nothing came out! it was bone dry in there. i knew it was leaking oil but didn't know all the oil came out. gasket sealer around the plate and put it back. filled it with 75-90 and Lucas Oil Stabilizer and took it for a spin.

The noise went down considerably. I can still hear it whine but its very faint. the more i drove it to slpash the oil around the less i could hear the whine. I tried to get it up to good speed (5th gear) but sadly living in NYC doesn't help. i hit all the other gears and brought it up into the high RPMs to hear it spin and whine more. so far 50%-75% better. I need to drive it to a Charity Event tomorrow, so more testing then.

The old t-case is out of a Disco II i believe.

 

DII would require some mods. With your case and the DII one I could set up a nice case and would send you a DII double cardon front shaft to eliminate vibes in the front. It would cost money to have it all set up but once it was, it would be sweet.

What year is the DII case out of? Does it have diff lock?

A cheap patch solution to the LT230 you have is to put in a half of a bottle of lucas oil stablizer. It would make the whine go down considerably.

 

DII would require some mods. With your case and the DII one I could set up a nice case and would send you a DII double cardon front shaft to eliminate vibes in the front. It would cost money to have it all set up but once it was, it would be sweet.

What year is the DII case out of? Does it have diff lock?

A cheap patch solution to the LT230 you have is to put in a half of a bottle of lucas oil stablizer. It would make the whine go down considerably.

D2 case is from my 2001, 60k miles on it.. but no cdl (hence why I swapped it)... plus the front output flange has already been salvaged to a d1 for the d2 conversion... We may have a spare D1 lt230 as well, gotta look into it..

 

So budz (sal) lives in Brooklyn and is going to hook me up with a Defender t-case to use! I owe you Sal!

How much damage do you think was done to my old case? Where should I look for wear once I remove it and put the new on in? The gears looked good when i took off the plate. No markings on the teeth.

I got thinking about it this morning, and I was running only a front drive shaft for about 400 miles on the truck. I also ran only a rear drive shaft too for about 200 miles recently. Would this locked position but too much added wear on the front and rear output bearings on the case?

 

The diff blows up first. Also the input bearings as they are furthest from the oil.

BTW, odds are the old one is probably fine. I have seen many run w/o oil for long periods without much issue.

 

Ron is certainly one of the boards gurus on this, so take his good advice. However, I'd still look at the transmission output shaft/ transfer case input gear spline relations. Because of its position in the transfer case, I would think that it would have been affected the longest as the oil level dropped, since the lower the oil level gets, the less lubrication it gets. My Discovery went along time with the whine before failing, and even at that it even got to the shop under its own power, but it wasn't pretty when we pulled it out.

Here are some photos of spline wear issues, if you haven't seen any. The shaft shown is threaded because it is from an LT77 (the older LT77 gearbox mainshafts had a nut on the end of the shaft). I also included a photo of the upgraded cross drilled input gear, which also has the added benefit of longer internal splines, to distribute the load better (the manual transmission splines were always longer, but the adapters for the autos, shown in front of the gear), show the a newer, longer spline and older shorter spline adapter.

 

Thanks so much guys! I will have the old t-case out this weekend and will look at it then. So far it seems to be running a bit better and not as noisy. The gears look good but that does mean that the spline can have some wear on it like Scott said.

Does anyone know the size of the drain plug? I need to get one.

 

It could have spline wear (or not) my experience is that they either have no wear or are nearly toast. Normally presents as a "clunk" not whine though.

Ron

 

It could have spline wear (or not) my experience is that they either have no wear or are nearly toast. Normally presents as a "clunk" not whine though.

Ron

Not to discount your experience, but my Discovery ('96 5-speed) started whining at highway speeds, and gradually got louder and louder. Beyond the normal clunkiness of Land Rover drivetrains, there was no noticeable clunk, until one day when I noticed this really nasty grinding/clunking noise as I drove slowly through a parking lot. At first I almost thought I had blown a CV, or maybe a wheel bearing was gone.

I started playing around, and noticed that if I put the transfer case in neutral, and let the clutch out in gear I could hear this not so nice metal against metal 'wobbling' noise, so I knew it was input side of the t-case. When we pulled the case, the rest of the internals looked pretty good..

 

I know, you mentioned that. It seems odd to me because there should be no whine at all because it would just run on the one side while moving.

As always, anything is possible. My tactic (which I am sure most real techs hate -- like Fidel and Pendy) is to indirectly find the problem by eliminatign the most obvious down to the least obvious issues.

IE, here, whining t-case most obvious = low oil

 

No problem! Let me know it work and enjoy the rally!!!!

So budz (sal) lives in Brooklyn and is going to hook me up with a Defender t-case to use! I owe you Sal!

How much damage do you think was done to my old case? Where should I look for wear once I remove it and put the new on in? The gears looked good when i took off the plate. No markings on the teeth.

I got thinking about it this morning, and I was running only a front drive shaft for about 400 miles on the truck. I also ran only a rear drive shaft too for about 200 miles recently. Would this locked position but too much added wear on the front and rear output bearings on the case?

 

Question on the whining guys...

I finally finished my rebuild of our d-90 that was totaled and since I've been driving it I've noticed a whine that seems louder than I remember it being. We didn't change anything on the transfer case, the only thing on the transmission that we changed was the clutch, but we did rebuild both diffs and put in 4.11's. Anyway, the whining I'm getting is very much as described - 4th/5th gear whine that varies with acceleration speed and goes away upon deceleration.

I pulled the PTO cover and the gear, spline, and bearings look good and were thoroughly coated in oil. There were very few signs of wear which is pretty good for 92k on the clock. The only thing of note is that the bearing cage (I don't know what else to call this, it's the cage that holds the bearings) seems a bit looser than on most newer bearings. I don't know how loose is too loose though and I don't know if this is causing the whine. Any ideas as to what else it might be?

 

I think I have 80k on my truck now I bought it with 41k. I have since day one been running Mobil1 throughout and Redline MTL. I have always always overfilled the transfer case by close to a quart. I overfill the gearbox maybe by half.

Does anyone know the VIN range on the updated input gears? Was it something that happened in the late 90's? My truck was built Feb96 so who knows what to expect. No I have neglected to pull the input gear I am almost afraid to.

What is the general consensus on this? Roughly what mileage are people getting out of the R380s before a rebuild? It seems like a taken care of driveline should last at very very least 100k. I doubt Ill ever stop whining.

 

I think Ashcroft transmission website has info on which xfer cases have cross drilled input gear. I gave up and put a lt230Q in my d-90, noise difference was like nite and day. Rest of the drivetrain still flunks, though, but not the boxes!

 

I was at 153K when i rebuilt mine R380. I was getting a new clutch put in and was told that the output shaft was nearly rounded off. When they tore the tranny down, they said it was in great shape except for the shaft. My transfer case actaully leaks now since they put the new gear in. Im guessing the seal isn't in there properly.

 

Where did you have your transmission rebuilt?

 

I had a local guy take it out and had it shipped out to Rob at SW Rovers. Came back looking brand new with a new gear for the transfer case. Let me know if you want check it out.

 

Yeah I would really like to see how it drives, would also like some insight into mine as well. Who did you have work on your truck here?