1976 Corvette, L-48, 4-Speed. Heres the Problem and what I"ve done to try and figure it out.
I have a vibration that is felt in the steering wheel/column, beginning around 2500 RPM in 3rd gear and all of 4th gear. The vibration is not constant but only when you press the accelerator. Let off the accerlator, and either come down or cruise and it disappears if not almost disappears. So its mostly when you press the accelerator, not in 1st or 2nd gear, only 3rd and 4th after reaching appx 2500 RPM and higher.
Next: The vibration is NOT felt in the gear shift lever at all, nor the gas or brake....and really nothing in the clutch (only comes up thru the steering column). Let off the gas and it disappears, push in the clutch and it disappears. Press in the clutch and rev the engine and its not present. So it really feels like a U-joint issue, but (see below)
This is what I've done (not all for the vibration issue tho):
1. New front sway bar link bolts
2. New shocks all around
3. New Rear Leaf Spring
4. New parking brakes
5. New rear sway bar links
6. New rear leaf spring bolts
7. New U-joints on the rear half-shafts
8. New plugs and wires, Distributor cap and rotor are fine.
9. Complete 4-wheel alignment
The main drive shaft U-joints look and feel fine, but have not been replaced. I have not yet checked wheel balance (air is fine). Again it only appears during acceleration as described above.
Any thoughts on what items and areas to look at next?? What am I missing?
Thanks
I have a vibration that is felt in the steering wheel/column, beginning around 2500 RPM in 3rd gear and all of 4th gear. The vibration is not constant but only when you press the accelerator. Let off the accerlator, and either come down or cruise and it disappears if not almost disappears. So its mostly when you press the accelerator, not in 1st or 2nd gear, only 3rd and 4th after reaching appx 2500 RPM and higher.
Next: The vibration is NOT felt in the gear shift lever at all, nor the gas or brake....and really nothing in the clutch (only comes up thru the steering column). Let off the gas and it disappears, push in the clutch and it disappears. Press in the clutch and rev the engine and its not present. So it really feels like a U-joint issue, but (see below)
This is what I've done (not all for the vibration issue tho):
1. New front sway bar link bolts
2. New shocks all around
3. New Rear Leaf Spring
4. New parking brakes
5. New rear sway bar links
6. New rear leaf spring bolts
7. New U-joints on the rear half-shafts
8. New plugs and wires, Distributor cap and rotor are fine.
9. Complete 4-wheel alignment
The main drive shaft U-joints look and feel fine, but have not been replaced. I have not yet checked wheel balance (air is fine). Again it only appears during acceleration as described above.
Any thoughts on what items and areas to look at next?? What am I missing?
Thanks
