Mailbag: Possible Causes and Cures for the (Vehicle) Shakes
M.K. • Darien, GA
Q: I have a 1983 Camaro Z28 with a rebuilt 305. I can’t drive over 80 miles-per-hour without the whole car shaking. I have tried different brands and widths of wheels and tires, but nothing has helped. I am stumped at this point—what should I be looking for?
A: We suggest checking the following things:
- Look for dents or missing weights on the driveshaft. Have it checked for straightness and proper balance.
- Check for bent rear axles.
- Check the engine mounts and transmission mounts to see if the rubber parts have cracked or are missing. If they are, replace them with new mounts—Energy Suspension polyurethane mounts are ideal performance replacements.
- If the driveshaft and mounts are OK, look for a damaged flexplate, torque converter, or transmission input and output shafts. Make sure the harmonic damper is the correct one for the engine, too.
simplest thing to do first is replace your U-joints…then look into the above suggestions
70 mph is the high speed lol
Did it shake before, if it didn’t reinstall the driveshaft 180
I had a 69 Charger that had the same issue at 90+ mph. So much so that if you let off the throttle fully, it would break the tail shaft housing on the trans. It turned out to be worn pinion bearings and too much gear slop. replaced all the bearings in the differential and the car ran smooth up beyond 140mph.
mine was pinion bearing
Also check brake drums/disks and suspension mounts and bushings. It could be something simple and easy to fix. I had a car that drove me nuts until I checked the suspension, turned out the bushings on the suspension were dry rotted and under enough stress (re: speeds over 70 mph) would cause heavy vibration.
You might also want to check your underarms make sure it doesn’t move up and down. JK steering linkages to make sure there’s no play. Check your front wheel bearings make sure there’s no play up and down left and right. Check your lower front a arm bushings. Cherokee rear drag link bushings. And check and make sure that your axles aren’t getting a groove worn into them from the rear axle bearings. And check your torque arm bushing it’s big metal plate runs from the rear end to the transmission
Idlerarm not underarm