74kelley

I just picked up a 76 c3, it has a vibration when you put power to it if you hold a steady speed, the vibration gets worse, ,,I the universals have been changed, we are putting it up on a lift tomorrow, is their anything I should be looking for?? thanks its bone stock

claysmoker

More info.

Stick or auto?

Does it shake when you rev it in neutral?

Any shake when accelerating or decelerating?

Check for play in the output yoke on the tranny and input yoke on the rear end for starters.

hugie82

Get the car vibrating and then Put the car in neutral and see if it's the engine.

74kelley

its an auto, the engine is smooth ,accelerating and when you hold steady, at 40-45 mph when it viberates shakes, ,it has new ujoints, when we jacked it up the pas side tire drooped lower than drivers side and the spring hanger bolt rubbed on wheel--it has had a 4wheel alignment, we asked the drive shaft people could they be out of wack?

74kelley

engine smooth,,wonder if the 1/2 shafts or the wheel bearings need attention,we are still looking

74kelley

its the harmonic balancer,, its loose and the rubber is falling off,,so we are going to replace it-thank you for your help

claysmoker

Glad you found it. I'm surprised you didn't detect it when revving the engine in neutral. Let us know how it turns out.

74kelley

gearbreaker

When you're done with the balancer you might want to get the exhaust pipe off the crossmember hole. The exhaust resting on the crossmember will cause vibration also.

74kelley