2000 Suburban Rear Diff noise

I have a 2000 Suburban, 150K, with a whine/roar when i accelarate. It seems to be coming from the rear end, and has become louder over the past few months. Any Ideas, what it would be? and if it would be easier or cheaper to swap the rear end out with a used one? It is a K1500 4X4, i believe 3:73 rear. Has anyone had similar problems? The noise also comes when going down a hill or decelarate mode, sounds like the gears in the rear? please help

While my 86 burb is much older than yours I experienced a similar noise/whine that sounded like it was coming from the back. I eventually traced it back to a leak in the transfer case resulting in low fluid level, filled up the transfer case and the whine disappeared. So I wouldn't limit your search to just one area as sound has a way of bouncing around.

Have you checked the fluid level in the transmission, transfer case and differentials? That's where I would start. You might also try putting the truck in neutral on a downgrade; if the sound is from the differential you likely would not notice any change but if its coming from the transfer case or transmission I would expect a reduction in noise as the load is lessened on those components.

In my area a differential from the wrecking yard is much cheaper than a new one, so it probably depends on whether you are doing your own work and your tolerance for risk - what happens if your used replacement grenades? In my area the wrecking yards stand behind their parts for 30 days but not the labor to install or replace. You can search http://car-part.com/ to get a feel for what a differential brings in your area.

Sounds like rear diff bearing noise.Not a big deal if you have a good tech that you like.No it is not cheaper to swap out with used.You have 2 pinion bearings about $35 each,2 carrier bears a $40 each some oil and about 3 hours lab.A smart monkey would do both wheel bears and 4 diff bears and be done with it.

Thanks for the info, I will check the transfer case, I know the trans, and rear diff fluid is ok.

Thanks for the info, the transmission shop said it is coming from the rear diff. probably a bearing. They quoted $800- $1200. I would like to attempt myself but i hear if you mess with the ring and pinion, it can be tricky.. I will have to do more research, before i dig into it. You are right it would be cheaper to replace everything myself instead of swapping out the axle. Thanks for the info, any help or hints are welcomed.

8-1200 bones,holy crap.We don't charge enough at my shop.R U serious? They looked at you in the eye and said that. 2 times as much as it should be,and your right, you have to know what your doing in a diff.

UPDATE<<<<

Hey Guys, Thanks for the Input. We Rebuilt the whole rear diff, 4:10 in my suburban, (We meaning myself and an experianced guy, who does it on the side). We found a bad pinion bearing and bad, carrier bearing. I went ahead and replaced the ring and pinion with a Richmond Gear set, along with all new bearings and seals. We got the tolerance dead on and the gear mesh pattern perfect. after putting back together it was alot quieter, however the bit#@h still has a bit of a whine between 45-55mph, mainly on the coast. I have not ruled out the transfer case or front diff, however it still does sound like the rear again. I could put back the original gear set, but I am not 100% sure the whine wasn't present before that either, as the bearings were making most of the noise. the guy who installed it was pissed and called Richmond, who will give me another set, (which could do the same thing).,, but they did say to expect some noise with the higher gear sets????I could try sound dampening material??? ..Or trade it in... Any suggestions as to how to eliminate this whine?

thanks

If the truck has the 8.5" ring gear, the higher ratio shouldn't be a problem. They are right that higher ratios can have a tendency to make a bit more noise on smaller carriers, but the OEM figured out how to hob the gear lead-ins to keep the noise down.

Unless you got everything perfect on the gear installation, you can still get a whine out of the rear.I would check the gear pattern again,before you go to the trouble to change them.Then again it could just be a characteristic of that specific gear set. White lithium spray grease is good to do a quick spot check like this.Good luck

I have to agree,in this case PERFECT means PERFECT.It must be.I'll bet you have a small case of gear whine.

After speaking with someone at Randy's Ring and Pinion, they said the Richmond will have a bit of a whine as they are a performance Gear. He sells the actual GM Set and a Yukon brand which is supposed to be quieter than the richmond set. Of coarse the suburban resinates the noise more than a truck would because the cabin is over the diff. I'm not sure it is worth swapping to another Brand, unless I go back to the GM brand, which is not as durable,but is quieter. any suggestions, or what brand of gears are people putting in these vehicles?

Once I had a noise like that and noticed a bit of seepage coming out of the pinion seal and I could swear that I even felt a bit of movement in the pinion when I wiggled the yolk with both hands. I then convinced myself that this nasty growling noise was coming from inside the axle. I sold the truck to a buddy for a song under the assumption that it needed a diff. He couldn't wait to tell me a week later that replacing the U-JOINTS fixed the problem!!!