Vibration at 70 mph
Thread Starter
Instructor
Joined: Jul 2007
Posts: 150
Likes: 0
From: Lewisville Texas
Vibration at 70 mph
I've got a harmonic vibration in the rear (at least it feels like that's where it's coming from) when I get up to around 70 mph and only under load, when I let off the gas and coast it stops.
I've been in the process of tracking this down for awhile now and can't seem to find it. I've replaced the T/A with new offset ones from Van Steel, rotated wheels and tires, had it realigned and it's still there. The only other things I think could cause it are u-joints and/or transmission yoke. How can I check these and is there anything else that could cause this?
Thanks
I've been in the process of tracking this down for awhile now and can't seem to find it. I've replaced the T/A with new offset ones from Van Steel, rotated wheels and tires, had it realigned and it's still there. The only other things I think could cause it are u-joints and/or transmission yoke. How can I check these and is there anything else that could cause this?
Thanks
Race Director
Joined: Feb 2005
Posts: 16,100
Likes: 17
All mine went away when I did TA bushings on my 78 (vibration at 70-75)...used rubber...
Seems bad u-joints would make wheel wobble...you can check those by jacking up rear...move wheel same as checking rear wheel bearings...other than that,maybe a drive shaft balance ???
Rich
Seems bad u-joints would make wheel wobble...you can check those by jacking up rear...move wheel same as checking rear wheel bearings...other than that,maybe a drive shaft balance ???
Rich
Drifting
Joined: Jul 2007
Posts: 1,712
Likes: 0
From: Tampa FL
You'll need to check the joints while in neutral. Jack the rear up (or back it up on a set of ramps) set the emergency brake, chock the wheels and make sure it's not going to fall. Check the front and rear u-joints and look for play (in and out, side to side, up and down) Any movement means the joint needs to be replaced.
If the u-joints check out it could be a missing weight, you would see a little rectangular spot where the weight used to be.
