What could it be?
Thread Starter
Instructor
Joined: Jan 2007
Posts: 115
Likes: 0
From: Jasper Indiana
What could it be?
After getting my car back from my mechanic, I noticed that there is a bad vibration coming from the rear end. He replaced the ring and pinion in the differential and replaced all four wheel bearings. The car had been sitting for six plus months. He said that he thought the tires had become squared off from sitting for so long without moving. He had the car aligned. I had two Dayton tires on front and two Firehawk tires on back when she sat. I replaced the two front Dayton tires with two new Firehawks. I kept the old Firehawks on the back, but they were taken off the wheels and put back on. Does anyone have any input for me? I would appreciate it very much.
Thank you
Doug
Thank you
Doug
Last edited by Doug Maitlen; Jan 9, 2009 at 11:21 PM.
Burning Brakes
Joined: Jul 2006
Posts: 1,108
Likes: 0
From: Sebastian Florida
Try putting your spare on. 1st on one side then the other, see if is one of your tires.
Did you drive it to the mechanic? If it wasn't there before it's probably not a tire.
Does it change with speed? Is it there if you shift into neutral?
Did you drive it to the mechanic? If it wasn't there before it's probably not a tire.
Does it change with speed? Is it there if you shift into neutral?
Limping across the line
Joined: Oct 2002
Posts: 5,299
Likes: 109
From: Peoria Az
Check your U-Joints.
When does vibe start? 55-75mph is probably tires
vibe coming on at 70mph + is more than likely a shaft out of phase(U-Joints)
Warped brake rotors will cause vibe but it usually comes on early 35mph
When does vibe start? 55-75mph is probably tires
vibe coming on at 70mph + is more than likely a shaft out of phase(U-Joints)
Warped brake rotors will cause vibe but it usually comes on early 35mph
Last edited by AzMotorhead; Jan 9, 2009 at 11:57 PM.
Pro
Joined: Mar 2005
Posts: 683
Likes: 4
After getting my car back from my mechanic,
This is the part of your message that I wonder about. I would call the local Corvette club and see who they could recommend for you to have the car checked out. I would have a second opinion done in this case.
Steve
This is the part of your message that I wonder about. I would call the local Corvette club and see who they could recommend for you to have the car checked out. I would have a second opinion done in this case.
Steve
Le Mans Master
Joined: Jan 2006
Posts: 9,192
Likes: 27
From: Boca Raton Florida
Sounds like something in that rear end isn't right, for a couple os reasons: 1, tires do not get squared off in 6 months unless they were flat sitting on the rims. 2, you had a mechanic replace all that stuff in the rear end and now it makes noise. The differential on a vette is a complicated piece of mechanical hardware, there is a lot of close trollerence fitting that has to be done in order for it to be right. There are also clutch plates in there (its a positrac) so it needs the correct lubricant and conditioner in there.
Same principal applied to the rear wheel bearings on the Trailing Arms, the factory tollerences are .005 to .008 which is way to loose, Forum experts set them to .0015 to .002.
Does youe mechanic KNOW corvettes or has he just worked on yours?
Same principal applied to the rear wheel bearings on the Trailing Arms, the factory tollerences are .005 to .008 which is way to loose, Forum experts set them to .0015 to .002.
Does youe mechanic KNOW corvettes or has he just worked on yours?
Le Mans Master
Joined: Nov 2003
Posts: 5,772
Likes: 694
From: Maryland
St. Jude Donor '05, '09, '15
Tires will flat spot, even overnight. Swap the tires front to back and see if the vibration follows the tires. If so you know you have a tire issue. Is the rear limited slip? If so it must have the proper limited slip additive. I use two bottles of the GM additive. Once the additive is installed you need to do some figure eights to mix and circulate the additive to the clutches.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
10 Things Every Corvette Owner Needs (2026 Edition)
Michael S. Palmer
8 Most "Only Corvette Owners Understand" Quirks and Problems
Pouria Savadkouei
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years
Joe Kucinski
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Instructor
Joined: Aug 2003
Posts: 104
Likes: 0
From: Newfane NY
A lot of good points here, but the best thing is to get some measurements done.
If you have already tried the new tires on the rear, and that has not fixed the problem,
a new problem has come up.
What was the origional reason for the rear rebuild?
Good luck!!
If you have already tried the new tires on the rear, and that has not fixed the problem,
a new problem has come up.
What was the origional reason for the rear rebuild?
Good luck!!
Le Mans Master
Joined: Nov 2003
Posts: 5,772
Likes: 694
From: Maryland
St. Jude Donor '05, '09, '15
Jack the rear wheels off the ground. With the car in neutral, engine off, turn one of the rear wheels by hand. If the other rear wheel turns the same direction it is LS. If the other wheel does not turn or turns the opposite direction it is an open rear.
Drifting
Joined: Mar 2006
Posts: 1,526
Likes: 2
From: Oak Ridge NC
If it is chattering while turning corners, then most likely clutches in the diffy...get the GM additive.Swap the tires front to back. Easiest thing to do.
If the vibration is getting worse while you are turning....something might be loose...lug nuts? Or possibly a missing alignment shim..maybe it fell out? So how much did he charge you to get the rear end aligned?
If it were me, I would swap the tires first. If this didn't fix it, I'd bring it back to this mechanic and watch him as he checks everything....he should not have delivered it to you without a test drive. Test drive would have surfaced the problem.