So I just had a 5" BDS suspension lift and a tranny rebuild done on my 2001 Ram Sport 4x4 Offroad, regular cab, short bed with 105K miles. Whenever I am going around 35mph or higher and I let off the gas completely or barely step on the gas I hear a somewhat loud grinding noise for about 2 seconds. It also does this when I shift into neutral and coast down a hill but it'll make the grinding noise the whole time if I do that. It's hard to tell exactly where it's coming from when I open up the sliding rear window. My guess is that its either from the tranny or the rear differential. I wouldn't think it's the tranny though because it shifts just fine, and also when I am hauling two quads around and the truck is loaded down a little bit with 700 pounds it doesnt make the grinding noise at all. I took the cover off the rear differential so I could put a new gasket on and replace the oil in it and I found a piece of metal about an inch long and an inch wide. I don't know where it came from or how long it's been there but I know it's not one of the gear teeth. I'm assuming this problem has to do with the lift that was put on by a shop. The rear diff wasn't re-geared or anything, i didn't think it had to be unless it was a 6" lift or higher. Has anyone ran into this problem before or have any idea what it could be or how to fix it? Thanks

 

I have no experience with lifts, but I'm thinking your problem is transfer case related. You might want to look into installing one of these even if it is not the problem right now.

http://www.drivetrain.com/parts_cata...ase_saver.html

 

+1 on zman with checking that. In addition, possibly check your driveshaft ujoints. Recheck all bolts from the lift that were torqued.

As for the rear diff, that piece isn't good. Do you have LSD? Does the piece you found look anything like this?



You might be able to reproduce the grind but putting truck on jack stands.

 

Hmm I will have to check on those. I don't know a whole lot when it comes to working on cars but I'm all about looking stuff up and doing it myself. I do have a LSD rear diff and the piece I have looks exactly like its a broken piece of the part you posted. What is that part? I would post a pic of it but I can't figure out how, I'm new to this forum as of today. But yea, it's a piece of that about an inch long. Is that a huge deal? And do you think that could possibly be the cause of the grinding noise? I'm looking into the driveshaft u-joint because that seems like a reasonable cause. Thanks for your help so far guys!

 

Broken piece in any gearbox is a big deal. Stop driving it.

Go to the FAQ/DIY and download the service manual and a parts manual. May want to p[ick up a Haynes at FLAPS as well. You gonna need 'em!

 

do you have a floor shifter for 4x4? if you accelerate heavy does it move a fair bit..?

 

Mine doesn't move much at all... check your engine/transmission mounts.

 

Will that broken piece he found in the diff cause movement there?

I must have missed OP's comment about anything moving.

 

If the piece you found is what I posted, then your c-clip(s) are broken. These are what provide the pressure on the clutch plates. You will hear grinding from this b/c the edge of the c-clip is rubbing on the clutch plate. Those plates the the far left of my picture are the clutch plates. Notice the shiney surface? That is the result of the edge grinding off the ridges.

Your carrier is fine, so you'd really want to replace the LSD. There are better options out there, but I don't recall any brands to mention. Some people here have replaced theirs and maybe could recommend.

To post pictures, there are 2 ways:

1. upload to this site as an attachment. A problem with it is typically having to reduce the filesize as there is a limit.

2. upload the photo to a sharing site like photobucket.com, imageshack, flickr, etc. For each photo a URL (link) is generated. Paste that URL here, but clicking this button:

 

DOn't know about the others, but onphotobucket, click on the IMG link. It automatically copies the link. Then come pback and paste it where you want it. Otehr may be that easy as well, I just haven't used them.