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Old 03-26-2010, 09:05 PM   #1
jimgmc
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Question Vibration problems

For some reason i cant figure out what is going on with my truck. I rebalanced my driveline and all for wheels, but for some odd reason after going over say 25mhp i get this vibration on the truck.

Last edited by jimgmc; 03-26-2010 at 09:06 PM.
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Old 03-26-2010, 09:27 PM   #2
ChevyTech
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Re: Vibration problems

Tire vibration because of balance shows up most in the 55 to 60 MPH speed range.

Drive shaft balance problems usually show up around 45 MPH.

For a problem that you can feel at 25 MPH you should be looking for a bent wheel, a tire with a bulge or belt problem, or a bent axle.

What year is the vehicle?
What vehicle?
Is it a four wheel drive truck?
Have you tried running it on jack stands?
Have you checked the U joints?
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Old 03-26-2010, 09:56 PM   #3
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Re: Vibration problems

Its a 1999 gmc 2500 2wd 350 auto not sure on rear ratio. When i bought the truck it had steel wheels and it did the same thing. The u joints look good. Would warped discs cause that?
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Old 03-26-2010, 10:22 PM   #4
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Re: Vibration problems

I don’t think it is the rotors.

I would put the back up on jack stands, with the truck running in neutral (NOT park), and the wheels should spin enough, and at a good speed, to see if an axle is bent. Have someone sit in the driver seat for safety.
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Old 03-26-2010, 10:30 PM   #5
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Re: Vibration problems

Thanx ill try that this weekend. This vibration is really getting on my nerves.

Last edited by jimgmc; 03-26-2010 at 10:31 PM.
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Old 03-27-2010, 01:34 PM   #6
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Re: Vibration problems

Just to add my $.02 worth....rotors on disc brakes that have any irregularity don't necessarily show up until you are on the brakes. My personal experiences include brakes that were heated up on a downhill run. That added to the effect...a pulsating brake pedal and a shimmy in the front end that quit when I got off of the brakes. My wifes' Lexus and my '00 Tundra both had that to happen to them.

Great thing is that my GMC has not been afflicted by any brake issues....short of needing pads and the rotors turned.
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Old 03-29-2010, 09:53 AM   #7
GASoline71
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Re: Vibration problems

Well... my 1994 GMC Sierra K1500 has developed a vibration at 40mph... and then at around 60mph. I can feel it through the steering wheel. Not bad, but annoying... and will prolly get worse.

Truck needs brakes all around. The rear brakes are starting to "surge" a little... I'm sure it's uneven drums. I was noticing this vibration about a month ago, and had the tires rebalanced and rotated. Now I can feel it through the steering wheel. So... I'm hoping it's just tires out of balance. I need to take it back to the tire shop, and have them rebalance.

I checked the front end this weekend. No worn ball joints... but one of the tie rods prolly has a little more play in it than it should. Could be contributing to the vibration I feel in the front. I checked drivelines too, and all u-joints appear to be in good shape. No slop either.

Good times... I hate chasing Gremlins... at least it's not electrical... those Gremlins are worse.



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