• If you currently own, previously owned or want to own an Avalanche, we welcome you to become a member today. Membership is FREE, register now!

Vibration Between 70 and 80 mph

woyster_07avy

Full Member
Joined
Jul 24, 2009
Messages
49
Location
Katy (Houston), Texas
First some history...  For the past year or so now I have been trying to get rid of a squeak/squeal that my wife has been hearing on my 2007 Avalanche.  I have gone down many different avenues including rear brakes, front hubs, u-joints, all 4 shocks, and finally front brakes.  The squeak/squeal was finally fixed...not sure why it was the front brakes as they were the newest of anything when the search for the squeak/squeak began.

In any case, prior to changing the u-joints there was no vibration.  Afterwards, there is a vibration that begins at about 72 MPH and gets better at around 78 MPH (roughly 70 to 80).  I changed out the u-joints myself and I have checked and rechecked my work.  The stock waxed-in u-joints were removed and replaced with MOOG/Precision part number 234.  After reading some posts on this and other forums, I even rotated the yolk and driveshaft 180? as recommended by some.

Being at my wits end, I took it to a local shop last week to have them look at it and see what they thought the problem was expecting them to have to balance the driveshaft.  The shop checked everything and even gave me kudos for the workmanship stating that my u-joint swap was "better than they have seen from some other local shops".  They said everything looked fine with the driveshaft...no missing weights, no apparent damage from the u-joint swap.  They concluded that the speed-specific vibration was a tire issue and recommended that I have the tires balanced/rotated.  After balance and rotation, the vibration still remains.  The tire shop did a thorough inspection of the wheels and tires while performing the balance/rotation and said everything looked good (by the way, these are the same wheels/tires before and after the u-joint swap).

Where do I go from here?  Do I take it back to the shop and pay the "several hundred dollars" to have the driveshaft removed and balance checked?  The shop is reluctant to do this as they said a driveshaft vibration will begin at lower speeds and just continue to get worse as speed increases.  I give them credit for not trying to get me to do unnecessary work.  Did I use the wrong u-joints?  Is there a make/model or part number that I should have used instead?  Is there anything else that I should look at?

Just a thought...could it have anything to do with the shocks?  Those were replaced the same time as the u-joints.  I don't see how it could be related, but just thought I would throw it out there as I'm at a loss here.

Thanks in advance for your help!
 
I had never experienced a vibration from shocks before either but I have seen some posts on here about others experiencing a shock vibration caused by loose mounting. What you describe is typically a drivetrain vibration. Do you feel it in the seat of your pants or the gas pedal or thru the steering wheel? Typically the drivetrain/driveline vibes are felt thru the seat of the pants or at the gas pedal. You might want to check the integrity of the engine and trans mounts. Your driveshaft could look good to the naked eye but still be out of balance or bent. I don't understand how checking that could cost hundreds. It only involves dropping the shaft and having a driveline shop mount and spin it up and check the balance and straightness.
 
The shop I took it to wasn't a driveline shop and I've actually thought about trying to find one and cut out the middle man.  I've also considered swapping the U-joints again and see if maybe I got a bad one...
 
Heck you could take out the driveline and carry it in to the shop and have them test it and if they say the u-joints are a problem then you can do it or they can address the driveline while it is there.
 
I KNOW THIS THREAD IS A LITTLE OLD BUT WAS THERE ANY FIX TO YOUR PROBLEM? I SAME ISSUE WITH MY 07... RIGHT ABOUT 74-75 MPH I GET A VIBRATION AND THEN GOES AWAY AT 79-80... NOT HORRIBLE BUT FOR SURE NOTICEABLE/ANNOYING .. JUST HAD THE FRONT PASSENGER WHEEL BEARING REPLACED WHICH HELPED.... STEERING WHEEL SHUTTERS A LITTLE TOO... TIE ROD, BALL JOINT, ETC??? ALSO A LITTLE CLUNK WHEN CITY DRIVING, OVER SMALL BUMPS IN FRONT RIGHT. MECHANIC SAID EVERYTHING CHECKED OUT AND NOTHING LOOSE.. BRAND NEW FALKEN WILDPEAKS SO DONT THINK ITS TIRES CAUSING VIBRATION...
 
26,000 miles, keep air pressure @ 35lbs, rotate every 5000 miles along with oil change. I have no issues with tire wear, never had an alignment.
 
Back
Top