Vibration diagnosis?
Thread Starter
Heel & Toe
Joined: Aug 2001
Posts: 21
Likes: 0
From: Marlborough MA
Vibration diagnosis?
I've got a significant vibration in the wheel, dash, and seat when driving my 1977 over 60 mph. I've already had the wheels balanced and double-checked at the fine level. I've had the wheels aligned. And the tires are new. Also, one wheel rim was hammered out. Also had lower ball joints and control arm bushings replaces in front,a nd all 4 shocks. So what else could this be? I do notice two things -- the vibration seems to come in repeating waves of 3 seconds of hard vibration, and one second of easing off. Also, when I go down a hill on the highway, and the engine is doing less work to maintain speed, the vibration eases off significantly. I don't get the vibration when revving in park or neutral. Any thoughts on what this is? Or is it normal for these cars? I hope not, because it's taking a lot of fun out of driving it. Thanks...
:sad:
[Modified by RickP, 6:07 PM 10/27/2001]
:sad:
[Modified by RickP, 6:07 PM 10/27/2001]
Burning Brakes
Joined: Apr 2000
Posts: 1,207
Likes: 1
From: Cave Creek AZ
Re: Vibration diagnosis? (Tom Johnson)
Couldn't it also be a worn U joint? I would think that a bad joint on the drive shaft would give you a vibration at certain speeds under load and stop when you let off the gas. I think that I would look there or one of the joints in the half shafts as well
just my .02
JoeB
just my .02
JoeB
Race Director
Joined: Dec 1999
Posts: 19,610
Likes: 778
From: Forked River NJ
Re: Vibration diagnosis? (woodworkr)
If you are only getting it at a certain mph it would be in the driveline somewhere. From the tranny on back. If it is only happening at a certain rpm it would be in the motor somewhere. I would guess a driveshaft or ujoint problem. I had my driveshaft balanced and it took away my vibration above 70 mph. With 4.11 gears the driveshaft spins pretty fast.
Thread Starter
Heel & Toe
Joined: Aug 2001
Posts: 21
Likes: 0
From: Marlborough MA
Re: Vibration diagnosis? (Gordonm)
Thanks, I'll look into having the shaft balanced. THe u-joint in front of the differential seems to have a worn spot on the rounded part, as if it's ben scraping against something as it turns.
