drivetrain vibration

I purchased a '99 Tahoe 4x4 with 110,000 miles on it back in March and noticed a vibration when going over 65 mph. The vibration has gotten worse, now I can feel it between 22-30 and I can't figure out what is causing it. I read several threads and have tried most solutions, including:

rotate and balance tires (285/75/r16),
wheel alignment,
tried a completely different set of wheels and tires (32/10.5/r15),
replaced all four u-joints,
replaced all four shocks.

It is a little better, but, I believe the new shocks are absorbing the vibration better than the old ones.

I also put the back end on jack stands, removed the rear wheels, and had my wife get it up to speed. I didn't see anything unusual but, I noticed the vibration when touching the body and also when touching the front wheel.

I am considering changing out the motor mounts and the transmission mount because they have alot of miles on them.

I have not had much experience with working on four wheel drives and am at the point where I may need to take it to someone to help diagnose the problem.

Any else had a similar problem? Any other solutions?

I am not sure this will help, but I have a 1996 2 door Tahoe with 175,000 miles. Mine has a vibration in it that starts at 65 MPH and will stop when going above 73 MPH. After lots of checking it seams to be torque converter shutter. If you fix it please leave a post as to what it was. Thanks Dave

I am not sure this will help, but I have a 1996 2 door Tahoe with 175,000 miles. Mine has a vibration in it that starts at 65 MPH and will stop when going above 73 MPH. After lots of checking it seams to be torque converter shutter. If you fix it please leave a post as to what it was. Thanks Dave

Very interesting...I've got the same thing on a 2dr '98. It's very noticeable by kind of humming sound as well as vibration in the steering column, rear-view mirror and gas pedal. Starts at almost exactly 60 mph and completely goes away at 68 mph. Only difference is that these vibrations began after I had to get a double-cardan CV joint due to an excessive trans to driveline angle following installation of a lift kit.

I've got a 98 2dr 4x4 Auto Mine shakes like a manual transmission in too high of a gear after staying at about 2400 RPMs going up a semi-steep hill. If I coast for abit after tit starts, it returns to normal. Today, the 'Service Engine Soon' light came on (I was actually happy about that) right before the shutter stopped. Without fail, before I could get the codes read, the service light went out....:banghead:
Anyway, here's an excerpt from some GM docs... Right Click/Save As

GM Service Info #1 (http://www.phoenixisp.com/4-6-2/service information.txt)

GM Service Info #2 (http://www.phoenixisp.com/4-6-2/service information2.txt)

i had that problem before on my astro van. it turned out to be the driveshaft. the balence weight had broken halfway off and was creating a vibration at high speeds. if you look on the shaft ,there will be a small metal tab with 2 small welds (tacks) on it. american axel corp. is the mfg . of most of the chevy driveshafts and they balance every d.s. like you would a tire.a new d.s. for my 2dr 97 tahoe is 135.00.
other than the d.s. i would look into the front bearings or cv shafts,and boots. i hope its a d.s though. the 4x4 fnt bearings arent cheap and are a pain to change. g/l

Thanks for all of the replies. I'm working two jobs right now so I haven't had a chance to check anything recently. After reading some other forums, I'm leaning towards the problem being somewhere in the front drivetrain assembly.

I'll update when I have a chance to do so more testing.

Well I have the same problem. 99 two door Tahoe, it starts after 60 mph and trails away after 70 mph. If I take my foot off the gas when going that speed it goes away. I also tried staying in third gear at 60 and the same vibration came back. Th U joints were replaced last December and I just bought new tires yesterday and the problem still exists. The vibration wasn't even there three weeks ago. I have to drive cross country here in a month and would like to have an idea what this problem is. Thanks,

Update: I think I have ruled out the engine and transmission, because I tried changing gears manually at different speeds with no effect on the vibration. The other morning on my way to work, I looked at the speedometer and I was going 73 mph with only minor vibration. I tried to get it up to that range again today and the Tahoe felt like it was about to shake apart.

Hopefully I'll have more time in July to fix my vibration problem.

I'm having the same problem... 60 mph - 75 mph shake. I don't feel it in the steering wheel, but the entire body of the truck.

**** Has anyone found the answer to this problem ***

I've found the problem in my case; the centering kit on this double cardan Spicer joint I have (front joint on the driveshaft/next to trans) goes out after a few thousand miles b/c it's next to impossible to lubricate with grease like you're supposed to.

For any who are unfamiliar with what I'm talking about here, it's basically two u-joints joined as a sort of single unit or joint via an "H" assy with a centering kit in between them--basically a spring and other parts that make sure both u-joints consistently share half of the total angle. When this spring breaks or other parts warp due to lack of grease, the amount of angle each u-joint is acounting for fluctuates constantly and results in heinous vibration. I have to use this type of joint b/c the lift I put on resulted in excessive driveline angle coming out of the transmission (the rear axle is shimmed up, so the angle back there is still close to stock) that will burn through normal u-joints in a flash.

Probably more than anyone cares to know, but my point is--from my understanding, everyone else here has vehicles at stock height with stock single u-joints that exhibit vibration problems almost identical to those that I experience due to this constantly failing joint, very interesting....

Well..

I took the rear drive shaft off to inspect the drive shaft U-joints. They look good and snug so I reinstalled.

I put the back of my truck up on jack stands, spun the rear tires up to 75 mph... smooth as butter.... so now I'm guessing something in the front. I've been told this vibration can occur from the front 1/2 shafts.

As I was taking a closer look to the front 1/2 shafts, I can see greese being spun out of the left side 1/2 shaft upper boot. So even thought all rubber boots are good on the front 1/2 shafts, I'm guessing I have a bad U-jont in the left and/or right 1/2 shafts. I plan to replace them next weekend. I'll keep everyone up to date on the out come.

I wish I had some news to report, but I haven't had many opportunities to work on my Tahoe.

I was wondering if it's safe to remove the front driveshaft (transfer case to the front differential) to rule out the half shafts.

I was wondering if it's safe to remove the front driveshaft (transfer case to the front differential) to rule out the half shafts.


NO...NO... NO....

Do not remove the 1/2 shafts and drive the truck... Don't ask me how I know...but don't do it... your wheels will fall off..... NO JOKE !!!!!!! If you remove the front drive shaft, the 1/2 shafts will still turn since they are directly connect to the wheel.

As for the front driveshaft... I don't know if you can remove it safely or not.

Well, I replaced the 1/2 shafts, I still have the vibration. While doing to the 1/2 shafts I noticed the Pitman arm and Idler Arm were very loose. I'll be replacing them today.

After replacing the pitman and idler.... I still have the vibration.

Issue resolved...

I had bad tires.. Even though I had them balanced several times and everyone said they looked good and spun good, I had them replaced and truck runs smooth now.

*** I went down from 285 to 265 size tire.

Good luck to everyone who had a similar issue.

I undestand the front hub bearings go out frequently. Yo have to buy the complete assy instead of replacing the bearing. I am not sure of the price.

I have a 97 2 Dr and I am getting a vibration or howl as well. Mine starts around 60 and gets worse the faster I go. I have had it into a well respected drivetrain place here and they can't figure it out either. They have checked everything and have had everyone in the shop look at it. Then I took it to my tire shop to have the tires balanced again. One tire was calling for 3lbs of weight and another was calling for 2lbs. Something very wrong there. Replaced tires and vibrations\howl is still there. I worried now that I will ruin another set of tires. Will keep you posted on what I find. Taking it to have an alignment at local stealer. Hopefully they can figure out what is wrong.

I have a 95 hoe with the vibration trouble but its very hard to find the vibes any 1 figure out their problem .. mine is starting to get worse ... :banghead:

I have a 2000 Tahoe 4X4 with a vibration coming from the transmission area. I can feel it around the arm rest area. My vibration starts at 60KM and continues till about 80KM/H.

I can't believe that we all have this problem and know one has a fix. My mechanic says that you just start replacing thing until we find the problem. This can be very expensive with a 4X4.

I started with the cheapest and easiest. I had my tires re balanced, this did nothing. My tires were worn out so had them replaced and balanced, still exactly the same vibration.

On this forum people talk about drive shafts, torque converters, U joints the works.
I just want it fixed. Has anyone found the answer? before I dig deep into my wallet.

I have a 2000 Tahoe 4X4 with a vibration coming from the transmission area. I can feel it around the arm rest area. My vibration starts at 60KM and continues till about 80KM/H.

I can't believe that we all have this problem and know one has a fix. My mechanic says that you just start replacing thing until we find the problem. This can be very expensive with a 4X4.

I started with the cheapest and easiest. I had my tires re balanced, this did nothing. My tires were worn out so had them replaced and balanced, still exactly the same vibration.

On this forum people talk about drive shafts, torque converters, U joints the works.
I just want it fixed. Has anyone found the answer? before I dig deep into my wallet.

Well let us start at the beginning
My mechanic says that you just start replacing thing until we find the problem
RUN !!!!!!!!!!! Run as fast as you can away from this guy..he has no idea what he is talking about!

With any vibration, you must start off with an understanding of rotating components and their frequencies.
Then a little math..and we can identify the rotating group that is the source of the vibration.
Not knowing some specifics make the math difficult, but some of the information you gave can help.
You will need to test drive the vehicle at the complaint speed and use either a reed tach or and EVA to find the answer.
Here is what I come up with.
Since you are complaining of a vibration between two speed, I split the difference and came up with 70 kpm or 43 mph.
If your vibration analizer gives you the following readings, you would diagnose the rotating group that is causing that frequency.
8 hz...tire and wheel assembly and its related components...out of balance
16hz...tire and wheel assembly and its related components...bent
24hz...tire and wheel assembly and its related components...cv joints/tripod joints

24-29 hz....propshaft and components...out of balance/out of round
49-58hz.... propshaft and components...U-JOINTS or working angles.


Your local GM dealer has the diagnostic tools to identify the cause.

Thank You for your reply GMMerlin.
Finally someone who knows what there talking about. I have had bad experiences with dealers.
Can you help me?

When I bring my truck in what do I ask for?
Do I just tell them what I'm experiencing and hope that they perform the test drive using the reed tach or EVA. Or do I request such a test drive. What should I expect to pay for such a test drive?

Will they be able to diagnose it that easily. You make is sound very straight forward. Are they able to say we got such and such a reading you need to replace this. Or are they going to do what my mechanic said. We thought it was this but you still have a vibration so it must be .....

I just want it fix and fix properly the first time. Not some guessing game were at the end I'm out of Money and I end up with a brand new truck after replacing allot of needles parts.

Thank You once again for your reply and any future advice.
Vince

Thank You for your reply GMMerlin.
Finally someone who knows what there talking about. I have had bad experiences with dealers.
Can you help me?

When I bring my truck in what do I ask for?
Do I just tell them what I'm experiencing and hope that they perform the test drive using the reed tach or EVA. Or do I request such a test drive. What should I expect to pay for such a test drive?

Will they be able to diagnose it that easily. You make is sound very straight forward. Are they able to say we got such and such a reading you need to replace this. Or are they going to do what my mechanic said. We thought it was this but you still have a vibration so it must be .....

I just want it fix and fix properly the first time. Not some guessing game were at the end I'm out of Money and I end up with a brand new truck after replacing allot of needles parts.

Thank You once again for your reply and any future advice.
Vince

Explain to the dealer your problem and request that you go with the technician to verify your concern and show them the exact problem you are having.
Also request that the technician that looks at your vehicle be 100% trained in manual drivetrain and /or steering and suspension and has an understanding of how to use an EVA.
Since you are paying for the diagnosis, request a completed copy of the vibration diagnosis worksheet as found in TSB 03-00-91-001C ..the information you want is the frequency reading and g force at the complaint speed.
You can reference the info I gave you in the post above and see if it matches up....it's hard to come up with the information without having the vehicle, but I think you may find that my math is pretty close.
I would suspect that at that speed you probally have a drivetrain vibration and not a tire /wheel vibration...but that is a SWAG :evillol:
That diagnosis to come up with the readings should take about an hour...next is narrowing down the source.

I just talked to a dealer. He said that they would charge from $50.00 to $100.00 CA 1/2 to 1hour labor for the test drive( diagnostic ). He also said that they would cancels the diagnostic charge if I had the work done there.
They are very busy at the dealer so I'm bring it in after the holidays. I'll let you know what happens.

i had the same problem @190k it was the carrier bearings in the rear diff ez job for me ... the driver side carrier bearing takes all the pinoin load on starts ... Hope this helps ...

i feel it in my truck fom 68 to 72 then it goes away after 72.. 99 tahoe