C2 Help needed to find vibration

[Gary Kemp]

I finally have my 63 convertible roadable. Not finished yet but close. I took it out for a short test drive and have a vibration between 28-35 mph. I get the vibration in gears 2,3, and 4. (I didn't try 1st). The vibration feels like it is under the seats or towards the rear end. I checked for loose bolts from the bellhousing through trans, driveshaft, axle shafts, rear spring, trailing arms and found nothing loose. Not being an experienced mechanic, I am asking for suggestions on what to look for and/or what to try to find and correct the problem. The wheels and tires have been balanced but no alignment has yet been done other than by eyeballing. Steering and tracking feel okay.

Help, anyone?

Gary

[Joe Kemp]

Re: C2 Help needed to find vibration

My Corvette mechanic had a 64 in his shop with the same problem, except the vibration started at around 40 and up. He tried everything. Finally in a last attempt he installed four new brake drums.... problem solved!
I'm not saying that's your problem, it just to show how difficult vibration diagnosis can be. I'd start by closely inspecting engine and tranny mounts, bearings and u-joints.

[roy braatz]

Re: C2 Help needed to find vibration

May be U-joints not seated or drive shaft need balanceing

[Wayne K.]

Re: C2 Help needed to find vibration

Gary,

As mentioned, check to make sure the driveshaft u-joint is properly seated in the diff.. Also if you didn't index the position of the driveshaft before removing you might try to install it 180 degrees front present and see if that changes anything.

[Nick Culkowski]

Re: C2 Help needed to find vibration

A soon to fail u joint caused similar vibration on one of my 67s. Also good advice to try rotating drive shaft 180 degrees.