Hi Gentlemen,

I have been lurking for a while and have decided to make my first post. I have a 98 1500 4x4 5.9 that is giving me a few problems

When accelerating ONLY, I am hearing a grinding noise coming from the rear somewhere. If I brake or let of the gas, it does not grind. I did some research on here and thought it may be a u-joint or wheel bearing.

Has anybody had this kind of the problem? Any ideas on what it might be or where I should start? Thanks in advance for your help guys.

Brian

 

In park, get under front drive shaft and reach into driver side axle. You'll see the ujoint and try to move it. If it has any play, then that is culprit. Do same for passenger side. You can also do the same for the front and rear driveshafts.

Those would be at least my first looksees based on your description.

Welcome to DF and since you've been lurking, add your truck info to signature to help ppl out. zman will tear you apart.

At top of forum: User CP > Edit Signature.

Edit: i know you stated "rear" sound. In addition to above, you may want to open rear diff and look. Other people here can comment further. Do you have LSD?

 

I had the same problem five or six years ago. Ended up being the LSD. Pull the cover and have a look. Mine had chunks of metal coming out with the oil.

 

I believe I do have a LSD. Thanks for the responses guys. I have one more questions : Am I safe to still drive the truck?

 

I would not continue to drive it with a grinding noise you will just make things worse and possibly add $$$ to the fix. It may or may not be the lsd you need to check it out along with the whole driveline. Put it up on jack stands and go from back to front.

You can find the service manual in the diy area for a 2001 download it, it will help you with info on how to check things out.

 

You might want to check the pinion for play, get the rear tires off the ground put it in neutral and turn the driveshaft back and forth there should not be any up, down or in and out movement. Had the same sound with an 8 3/4 back in the day with the rear off the ground and a helper you could see the pinion going in and out under accel and decell. Tightened the pinion nut and it was good. I got lucky...usually the only way you will have slop in it is if a bearing is going bad.


One more thing..is it a 4X4? There is a snap ring that breaks that will let the output shaft move around and make some nasty grinding noise. It is an easy fix though just have to pull the tail housing off...no need to drop anything..well except for the driveshaft.

 

Newman1367, I really dislike it when you post.

Reason is b/c then I see your picture in the sig...and it makes me yearn like no other.

 

Ditto.... Only mine was more of a gear whine on decel only and ended up being from LSD chunks damaging my pinion bearing.... had it all rebuilt and been good since

 

I also have a grinding sound coming from the back of my 98 1500, at first i thought it was the rear brakes but it definitely wasn't, i got under it and was looking, the U-joints didn't look bad but then i grabbed the drive shaft and tried to move it and it had a little bit of play to it where it comes out of the transfer case, not much but was noticeable. I have had people tell me different thing about what they think the noise is, so I'm hear to ask y'all what you think it could be and how to fix it.

 

jack it up, and spin things by hand. See if you can feel anything.