vibration in rear end

I have a 2000 Blazer LT that has a vibration in the rear end at speeds between 60 and 70 mph. I have had the tires rebalanced and had new tires put on, swapped the wheels around and still the vibration persists. Anyone ran into this ?

I had a 96 silverodo and the U joint or constant volocity joint was going out and caused the truck to shake I could also hear a clanking sound to at low speeds.... Check your rear diff oil to maybe its low... Good Luck

bad U-joint.

That or time to check your rear diff fluid.

GM representative says this is a known issue - there is no fix for it !!!--- all u joints, differentials, shocks, drive shaft etc check out OK!

He is full of crap bro.

There is no known shaking with any of the Blazers.

They are all more or less the same from 1995-present.

Are you running Goodyear tires?

I am running Goodyears now, Goodrich before that -Gillettes before that- same vibration - can't feel any difference when I changed tires. I agree - there are only so many things under there to cause a vibration, it will be a matter of finding it.

It will be tough.

Do you have any noise with the vibration?

Mainly the rattle of interior components being shaken loose by the vibration - but maybe a faint whoom - whoom -whoom noise. Doesn't sound like a u joint rattle or a clicking

have you taken the rear hubs off and looked at the brakes?

Check the rear bearings?

I have a 99 Silverado that has the same problem. Are you sure it's coming from the back? I bought new tires because the original set had uneven ware on the inside of the tires like the truck has been bouncing. The tire place said it was from not having the tires rotated. Since I was not the original owner, I thought my problems were solved, but 70k miles later the Michelins have the same ware pattern and my truck still feels like my tires aren't balanced and I take it in every 15k miles for balance and rotation. I have read a thread on this forum that gives detailed instructions to repair this problem, but I can't find it again. When I do find it or if someone can shed some light on this matter, I will pass it on to you.

I agree with BlazerLT, I would also suspect the U-Joints. How were they inspected? If you have the type that are held in the drive shaft with the injected plastic, I am wondering how your mechinic inspected them since you really cannot take them apart without damaging them. I'd double check the U-joints.

BlazerLT, how would you suggest to inspect the U-Joints without damaging them?

However, Since you're running into brick walls with the rear end, you might just check the front wheel bearings too. When my Front wheel bearings went out on an 82 Olds, it sounded like an airplane noise and vibrated to beat the band at higher speeds, but simply spinning the wheels while jacked up didn't reveal a problem. Once I pulled the bearing out, the metal flakes were a dead give away. It may be possible that the vibration/noise is transfering.

U-joint can't really be inspected, but only replaced.

There are two u-joints and it is best get them serviced anyways.

It is that or a rear bearing problem.

Exactly my point! Simply crawling under a jacked up vehicle and trying to shake or twist the drive shaft won't really tell you much about the condition of the U-Joints at high speeds unless they're about ready to fall out.

By "getting them seviced" I assume you mean replaced, as the factory U-Joints don't normally have grease fittings. I would replace them in a heart beat before spending any more money on tires, brakes etc.

Yea, true, I would get them both replaced first before moving on.

Also, a good check is to put the truck in reverse, and then to drive and listen for a clunk coming from the rear of the vehicle.

Thanks for all the info - I jacked the Blazer up and physically checked the u-joints, they felt OK but I will replace them anyway when I replace the rear wheel bearings. There is a little movemant in bot rear wheels when you grab them and move them up/down or side to side. Still cant hear any clunks when I go into reverse.

Hmmmmm.....

Does sound like your rear wheels bearing have a little too much play in them.

Hmmmmm.....

Does sound like your rear wheels bearing have a little too much play in them.

When you pull off the rear brake drums, look to see if there is oil coming out from around the axle. If the bearings are loose and/or worn it could cause the seal to leak as well as causing the vibration.

I have a 2000 Blazer LT that has a vibration in the rear end at speeds between 60 and 70 mph. I have had the tires rebalanced and had new tires put on, swapped the wheels around and still the vibration persists. Anyone ran into this ?

Does it vibrate no matter what position the gas pedal is in? So if you floor it does it still vibrate? or does it only vibrate when the gas pedal is about 1/2 way down?

I don't get why the throttle position would cause a rear vehicle vibration?

I don't get why the throttle position would cause a rear vehicle vibration?

I asked because mine has a rear end vibration between 50-60 mph, but only with the throttle about 1/2 way down, and I have changed u-joints, brakes and checked everything I can think of and still cannot figure it out.

It does not matter whether I am on the gas or not, vibrates coasting or accelerating

What about your driveshaft? It could be out of balance. Check to see if any weights are missing.

Does it hunm at all or is it a straight vibration with no sound?

Hey let me know if u find anything out. I have the exact same problem, I have a 2002 Blazer LT 2 door and the wobble seems to start at like 69mph and +. I've had the damn thing aligned twice, balanced 3 times, new tires on the front, taken it to three different places - 2 tire shops and 1 mechanic, have had the tie rod ends replaced (the looked 'loose') and the center arm of the steering replaced.... same exact problem. I've only owned the car for 3 months, the wobble is enough to prevent me from driving above 65mph! Only 40K miles on the car. No wheel dents or dings.

I am still sticking with the U-Joint theory. 6 of the 8 bearing caps on the Factory U-joints are sealed into the driveshaft with injected plastic and cannot be inspected. The remaining two are u-bolted to the rear end yoke. These last two bearing caps can be inspected, but don't give yourself a warm fuzzy about the first 6 by lookingat the last two. If your drive shaft is not missing any weights, and you've exhausted all other efforts, replace the u-joints.

I think Ill go have the U Joints looked at/replaced ASAP, I'm not totally stupid about cars, I can go general maint. but I have no idea what a U Joint is hehe

On rear wheel drive vehicles, the U-Joints are the cross-shaped or X-shaped swivels that are located on each end of the drive shaft. Each U-Joint has 4 bearing caps, one on each end of the cross. These bearing caps are full of small needle bearings, and are filled with grease. When the U-joint goes bad, it usually means that the needle bearings have worn ridges into the shaft of the U-joint, and in some cases the needle bearings will disintegrate completely, and the bearing cap will be full of rust and dirt. In either case, it will cause the drive shaft to vibrate and make noise, increasing both with speed. You may sometimes hear a clunk while reversing directions of the vehicle resulting from the U-Joint shaft slapping back and forth in the bearing cap that has lost its needles. In extreme cases, the U-Joint can snap and your drive shaft ends up in the road.

Older style U-Joints were pressed into the driveshaft, and held in place with horseshoe shaped clips or snap rings. But the newer ones are held into the drive shaft with injected plastic. To remove the injected plastic type, it requires heating the drive shaft yoke until the plastic melts. The replacement U-Joints will have clips or snap rings to hold them in place. If you have them replaced make sure you get the type that have grease fittings on them so you can periodically grease them.

Wow Thanks for the info!

Hey let me know if u find anything out. I have the exact same problem, I have a 2002 Blazer LT 2 door and the wobble seems to start at like 69mph and +. I've had the damn thing aligned twice, balanced 3 times, new tires on the front, taken it to three different places - 2 tire shops and 1 mechanic, have had the tie rod ends replaced (the looked 'loose') and the center arm of the steering replaced.... same exact problem. I've only owned the car for 3 months, the wobble is enough to prevent me from driving above 65mph! Only 40K miles on the car. No wheel dents or dings.

Have you checked the REAR wheels, looks like you are always focusing on the front.

Have you checked the REAR wheels, looks like you are always focusing on the front.

Believe me, I have taken it to two different National Tire and Battery stores - twice to one NTB, and I have taken it to a BP ProCare, I have asked all 3 places to check the tires and the wheels for any dings dents blagh blagh blagh if there is something wrong they can't find it :-( the front tires are 2 months new.

Believe me, I have taken it to two different National Tire and Battery stores - twice to one NTB, and I have taken it to a BP ProCare, I have asked all 3 places to check the tires and the wheels for any dings dents blagh blagh blagh if there is something wrong they can't find it :-( the front tires are 2 months new.

How about having them check beyond the tires and check the bearings etc.....

Don't get a tire store to check it out. Get a mechanic to check the bearings.

I am afraid my 02 Blazer may have the same problem.

I thought the tail was to light and added a subwoofer box to the trunk from my old car to the new one for the time being.

Box weighs about 100 pounds give or take but probably more.

Seemed to calm it down a bit. I wonder if this has to do with the suspension?

I am afraid my 02 Blazer may have the same problem.

I thought the tail was to light and added a subwoofer box to the trunk from my old car to the new one for the time being.

Box weighs about 100 pounds give or take but probably more.

Seemed to calm it down a bit. I wonder if this has to do with the suspension?

You should post your own thread so we can help you separately and not defect this thread help for yours.

Please post your own thread, this is not fair for this guy.

I didnt mean to detract from his thread, I am just giving input to the issue not attempting to look for my own answers.

Check the driveshaft itself for straighness/balance. If its dented at all, thats enough to throw it out of balance. Take it to a speed shop equipped to check this. Sounds like you have eliminated most other potential causes (tires, u joints, rear axle bearings)

What's a speed shop? Do you think taking it to a real Chevy Dealer would make a difference? I've been to National Tire and Battery (NTB) and (BP) ProCare....

Check your local yellow pages under "drive shafts" for shops that specialize in this service or just automotive machine shops. Sounds like the dealer has already given you the "its a known problem" line of BS so I would personally spend my money elsewhere. Most tire and general repair shops are are not equipped to check driveshaft straightness and balance. Keep in mind that the driveshaft is spinning anywhere from 3.08 to 3.73 (4.11) times faster than the wheels at any given speed depending on the axle ratio so ANY imbalance is going to cause a lot of vibration.

Hey let me know if u find anything out. I have the exact same problem, I have a 2002 Blazer LT 2 door and the wobble seems to start at like 69mph and +. I've had the damn thing aligned twice, balanced 3 times, new tires on the front, taken it to three different places - 2 tire shops and 1 mechanic, have had the tie rod ends replaced (the looked 'loose') and the center arm of the steering replaced.... same exact problem. I've only owned the car for 3 months, the wobble is enough to prevent me from driving above 65mph! Only 40K miles on the car. No wheel dents or dings.


I have changed the rear wheel bearings and still have the vibration. Going to do the drive balance thing next. I did note a lot of 'slop' in the differential though.

Phil, I assume that you have rear disk brakes (my 2000 Jimmy SLE does). Have you checked your Differential fluid? Please clarify what you mean by a "lot of slop" in the Differential. You might try draining the Rear-End fluid and see if you have any metal flakes in the oil. It might cost you a rear-end gasket and some oil, but it might be worth it. (why they stopped putting drain plugs on rear-ends I'll never know). But overall, I'm sticking with My U-Joint theory. When you find the answer, please let us know so we can end this thread!

Well I just bought a 2000 LT with 87000 and brand new tires and a littel vibe at about 65 mph. Also noticed it could use shocks .I wonder if a minor balance problem is more aparent with weak shocks.

Yes, no question about it.

I have already put new grease in the rear end, when I put the new wheel bearings in. No metal flakes in the oil at all. I have also noted that the shocks are fairly new, and this is the third set of tires I have put on the blazer, with multiple rebalnces on each set. It does indeed have rear disk brakes.

Well, it sounds to me like you've just about ruled everything else out except the Driveline and U-joints.

What about slightly warped rear rotors?

I am having a similar problem, but when i hold the brake in and shift to drive or reverse it clunks? I had the rear u-joint replaced think it could be the front? oh yea 97 blazer LS

Yes, replace the front joint. A clunk when shifting from drive to reverse without "moving" the vehicle or steering wheel is a bad U-Joint! And don't wait, the clunk means that the bearing cap or caps have lost their needle bearings and you are at risk of snapping the U-Joint in half.

anyone check theire rear rotors for warping?

anyone check theire rear rotors for warping?
warped rotors will be noticeble by a pulsing feel in the brake peddel and a bad warp will be felt as a jerky stop. but so far I've never noticed a vibration from a warped rotor ,not to say it can't happen but you will get the other symptoms first

Sorry, I am helping the thread starter who is the one that asked the question.

Sorry, I am helping the thread starter who is the one that asked the question.
Please forgive me if I've stepped on any toes. But I didn't know this forum was only for one person to receive help and only for one person to give help. I have blazer with the same problem , and over 20 years experience in automotive and aviation mechanics

Please forgive me if I've stepped on any toes. But I didn't know this forum was only for one person to receive help and only for one person to give help. I have blazer with the same problem , and over 20 years experience in automotive and aviation mechanics

Then start your own thread.

This thread is dedicated to helping this thread starter.

Let's please respect him and not whore his thread.

Hey philsblazer, you should check out GM's Technical Service Bulletins (TSB's). I got a long list of these TSB's for my 99 Silverado. TSB #00-02-35-004 may help you out it gives the parts and detailed instructions to repair these known issues. Try this link www.agmlemon.freeservers.com/GeneralBulletins.html

good idea Bobbido found gm tsb 02-04-21-005a dated feb. 2003 in a listing of s10 blazer tsb,s. The only discription i could find was for an Escalade, It reads"If the drivetrain leaks , makes excessive noise, VIBRATES, slips in four-wheel drive, or exhibits a hot odour, the front axle may have excessive preload in the pinion or carrier bearings.
Its not the first thing I'd tear into but its something to think about.

Hey Philsblazer, did you ever change your U-joints? How about your Rear rotors? Give us an update on where you're at with this!

I have replaced rear bearings, shocks, tires, u-joints, balanced drive shaft, replaced grease in rear end and took it to two more dealer ships still vibrates. One of them told me that in the 2000 model year range that GM took a lot of two wheel drive Blazers and made them 4 wheel drives and that they were told that this has caused this issue. Anyoone ever heard this before?

Why are you focusing everything on the rear end?

Have you checked the alignment on the frontend?

I once replaced u-joints and didn't center them, had the same problems as before replacement (shimmy, shake)...so for time sake if you replace them your self, center them and check for free movement, lesson learned here...

My turn to take a shot st this problem. I have delt with a lot of vibration problems over the years.
1. When you are driving where in the car to you feel the vibration most?? In the steering wheel?? in the seat of your pants your but ?? with your feet on the floor?
what area is the worst.
Anything felt in the steering wheel is from the front of the car and it depends where on the floor say like on your feet is front and the seat of you pants butt is from the rear ooops no pun intended we have to find that area first.
Sec ALL GM dealers must have a vibration tool to help locate the vibration and a set of microphones and recording box that we set up under the trucks to find any noise that would lead us to the vibration.
Does it ever do it in 4 wheel drive hi lock.
This problem could be a transfer case vibration

The steering wheel is rock solid stable, all of the vibration is coming rear, and the farther back into the rear of the vehicle you go the 'better' you can feel it.. It also vibrates in 4 hi as well as 2 hi. I had the drive shaft balanced after I installed the new u-joints. The dealerships used thir vibration analyser and said that it was a drive train vibration, they ruled out engine and wheel by the frequency of the vibration.

If this was under warranty, I would have them replace the axle.