96 4x4, Rear end makes a whining noise when I let off the gas or on deceleration is it normal in these trucks?....PO told me he had just replaced the transfercase and I'm hoping their isnt any issues with it or the rear axle but its a loud gear like noise kind of like my jeep used to make when threw it in reverse....
It doesnt seem like it tranny related at all and is most noticeable when the rear window is open sometimes I can make out a vibration that goes with it....
Any Ideas?
thanks.
oh yeah truck has a 4 inch body lift and heavier coils and add a leafs.... and new 35" mudders if it matters

 

its normal if there is a problem. do you have an lsd rear end?
check your transfer case fluid level and change your differential fluid in the rear end so you can inspect the gears while you have the cover off.

 

bad pinion bearing will make one loud whine on acceleration, and another, growlier whine on deceleration. its a big job to remove the carrier and pinion and press in new bearings. i'd guess several hundred dollars in labor. an alternative is to find an entire rear end assy in the junk yard, and just swap the whole thing. sometime you can find one cheap.

 

this guy might still have one in dansville, ny
http://buffalo.craigslist.org/pts/1347548721.html

edit: wait, do the 2500's have a 9.25 rear end? can't remember. dunno, either way you might want to check that truck out for other parts if you need anything.

 

thanks for the responses....not sure on the rear end or even what gears are in it...asked to PO (second owner) and he said he didnt know. But it seems to have plenty of low end with the 35" tires on it and the speedo is correct so I'm not sure if it was gearing or programming... I actually came across that truck a while back right after I bought mine on craigslist that is an option if the gearing is right...I have to take mine in because of a recall email on the hood latches I got from Dodge and I met a guy who works at the dearership a couple weeks ago when I bought a rollbar from him on craigslist who has the same truck. I'll ask him if he or someone there heard the noise before.
I dont really hear anything when driving just on decceration but I wouldnt doubt it if the rear is shot especially since he blew the transfercase...stuff I should have noticed when I bought it but was in a hurry when I looked it over.

 

Before you go out and just buy a new rear end or anything. I'd check your gear lash see where your gears are riding on each other and if they are worn out. The noise your hearing coming from the rear could be just a poor set up on the rear gears if they have been changed. Its easy all you have to do is take your rear diff cover off and clean the gears with some brake cleaner and then apply some gear marking paint. Then just run the paint on the carrier gear back and forth on the pinion. After you do that see where your pinion gear is riding and I bet it is on the far inner or outer edge of the carrier gear and thats the noise your hearing on decel. If so you just have to have the rear end re-set up with some new seals and bearings and it will be a lot cheaper than just buying a new one.

 

This makes sense and I do plan on opening it up to take a peak around, thanks.