Transfer case

[Kmiller86]

I had a very loud grinding/metal on metal sound coming from under the car. It sounded like the transfer case to me. Took it out and drained the oil from it. The oil only had 1500 miles on it and i could see a nice silver film in it. I think its time for a new one. Would you recomend to get one from a salvage yard. I can get one for 450 but the guy doesnt know how many miles were on the car it came off of. Any advice would be great

 

[4pistons]

A silver film won't make a grinding noise. If you can turn the input and output shafts on the Xfer case freely by hand then that's not your problem. Unless it ran dry of oil then I doubt it's shot. You can pickup a used Xfer case for $200 or less on the Trader. $400 is WAY too much!

Rick- '91 GSX

 

[Kmiller86]

Well i put new fluid in it and it still makes that noise just like before. Let me explain more about the problem since you dont think its a transfer case problem. It will make this grinding/ metal on metal noise when engine breaking(which i dont do too much) from 3300 rpms to 2200 rpms only! never does it higher or lower. It will also do it while coasting at part throttle (5% throttle). I do have a welded center dif from shep, that is why i thought that it could be a xfer case, there is more stress on it. This is also weird the noise almost dissapears when i have the a/c on. It will dissapear completly when its doing it and it turn the a/c on quick. Im at a loss. Its been doing this for a few weeks now. Any far out ideas?

 

[4pistons]

The DSM Xfer case is a very simple device. It only has two gears, that are constantly meshed, and some bearings in it. And since it is constantly submersed in oil (I assume you haven't run it dry) not much can go wrong. Nothing "slips" or engages and disengages. They can be "broken" but since some 10 and 9 second cars still use the stock one I doubt you broke yours. And a welded diff isn't putting any more stress on it than a 10 second car does! I've been driving on my welded diff for 5+ years now without any problems.

It's very hard to pinpoint a noise or vibration without being there. But don't get so focused on what you THINK it might be when some simple diagnosis could narrow it down. When you had the Xfer case out did it turn freely by hand? If yes, then it's not that.

Do you have an aluminum flywheel by chance?

Rick - '91GSX

 

[Kmiller86]

Yes I do have a alum. flywheel. The noise started when i put in the new clutch/flywheel/shep racing tran. What would the flywheel have anything to do with it?
Thanks

also I have a stage 5 SPEC clutch and pressure plate. ITs a full faced disk sprung. Would this have anything to do with it.

 

[GritsnGravy]

Since you have a weldd center dif., couldn't you just pull the transfer case off and drive it fwd to see if it is the transfer case. If it is still making the noise, then its not the transfer case.

 

[4pistons]

would the flywheel have anything to do with it?

Read this entire thread - http://www.dsmtuners.com/forums/showthread.php?t=179513

couldn't you just pull the transfer case off and drive it fwd

YES, but the hard part is what to do with the driveshaft. You'd have to take the whole thing out. PITA. If you had the Xfer case out you could easily inspect it on the bench for damage.

Rick - '91 GSX

 

[Kmiller86]

Read this entire thread - http://www.dsmtuners.com/forums/showthread.php?t=179513

Quote:

Wow ive never heard of that. The only thing it didnt answer was should it be balanced right away or can it be driven on for a while. This is my daily driven car so i would like to wait till winter to remove it and balance it. Thanks alot for the replies.

 

[4pistons]

should it be balanced right away or can it be driven on for a while

I've been driving mine like that for a year now. Next time I pull the tranny it's getting balanced. It's a little annoying but I don't think it's hurting anything.

Rick - '91 GSX

 

[Kmiller86]

I think im going to email SPEC and see what they think also. Im very thankful for the responses. I almost ordered a new xfer case. I would have never even thought of it being the lightweight flywheel and the pressure plate. Thanks again

 

[Kmiller86]

Well 4piston you were correct on the alum. fly. I emailed SPEC and this is what they had to say

It's gear rattle from deceleration, not balance. Yes, it is normal
with an
aluminum flywheel.

Thanks,