Help! 1989 Callaway

[BOCG]

I have vibration which becomes noticeable at low speed and again at around 60mph. Seems like I can drive through it if I drive at higher MPH. I have had car checked out by non corvette specialist. They did not find anything wrong with wheel balance, shocks or anything else obvious. They thought it could be transmission related such as unbalanced half shaft. Any one have a similar experience of suggestions? Thanks tom

 

[boomdriver]

have you pinned it down to the drive train or rolling assembly?

get it to the worst vibration and push in clutch...see if it stops. Then place trans in neutral...see what happens while coasting. If it still vibrates in neutral at 60 mph then its wheel/tire bearing related. If it stops but tries to vibrate as engine is revved and when you put it back in gear and apply power...its engine/drive-train. There it could be clutch, crank balancer (those get destroyed on hi-torque engines) or a bad bearing in the trans.

Most times you will find something in the drive train or clutch plate or throw-out bearing. The typical wear parts. As long as you are comfortable that it is not an engine misfire of some sort...focus on drivetrain after the rolling test.

If you are parked and rev the engine to various rpm...do you feel anything? revving and holding that rpm for 1-2 seconds?

 

[BOCG]

thanks

Boomdriver, Thanks for the reply. I will take it out tomorrow and put it through the various tests you suggested. Will let you know what I find out. Tom

 

[BOCG]

Uodate

Boomdriver, Took it out and tested against your recommendations. Seems like it's back to wheels/tires. Vibration stays same when clutch in neutral. No vibration while stationary when revving. I have already replaced two wheel bearings recently, maybe other tow need sale. Will check it out next week. Thanks, again. Tom

 

[boomdriver]

Boomdriver, Took it out and tested against your recommendations. Seems like it's back to wheels/tires. Vibration stays same when clutch in neutral. No vibration while stationary when revving. I have already replaced two wheel bearings recently, maybe other tow need sale. Will check it out next week. Thanks, again. Tom

Well, thats about the easiest way to pin it down. If its looking like wheels, it might be a worn bearing. Look for a wad of grease inside a wheel rim, or knots on the inside of a tire.

 

[WhalePirot]

all that labor for the bearings, I'd surely replace the U-joints on the half-shafts; maybe also the driveshaft's.