Another vibration thread!

[Mac442]

Getting a general “vibration” when I hit about 50-55 mph. Gets worse for a bit when I let off the gas. If I hit the gas again it gets a little better. Only happens around 50.

1985 442 only has about 67000 miles on it. Engine has about 1000. Trans 2500.

I have replaced the body bushings and have the Jeep steering shaft. Since the vibration started I also replaced the entire front suspension, and trans mount.

U joints about 7500 miles old. But I wondering if this could be driveshaft/u joint related. Stock driveshaft. Weights are still there. Any thoughts or similar experiences would be great. Thanks.

 

[83StreetMachine]

Definitely driveshaft

I'd take it out and check the u-joints, for any failures, and have it rebalanced.

To be honest I'd just replace the u-joints and have it rebalanced

Also make sure there is no big dents along the driveshaft either

 

[pontiacgp]

sounds like it could be the idler arm....

 

[Mac442]

Since I hate to leave threads unresolved (and I still have the vibration) I’ll keep this going.

I was finally able to take the 442 out today for a drive. When it vibrates over 50-55 (most when letting my foot off the gas) I shift into neutral but the vibration still is there until I get back under 50. Does this still seem like u joints? I’m trying to narrow things down. Thinking of getting tires balanced just to eliminate that. And I replaced the idler arm when I redid the suspension.

no dents or anything on the driveshaft. I joints were replaced about 4000 miles ago...20 years ago.

 

[Streetbu]

Where do you feel the vibration? Steering wheel or the seat? Is it violent and slow, or very high speed and kind of minor?

 

[pontiacgp]

put the car in the air and have axle stands to keep the rear at ride height, have some bring the speed up to where you feel the vibration and take a look to see what is vibration. If you do not feel any vibration then it has something to do with the front wheels, bearings or rotor

 

[airboatgreg]

Pull the driveshaft and check the travel and ease on the ujoints. Should not be stiff of catch. Also check the trans mount

 

[Mac442]

Where do you feel the vibration? Steering wheel or the seat? Is it violent and slow, or very high speed and kind of minor?

Definitely coming from the rear of the car, I can see the trunk lid shake violently when driving. Odd thing is, it’s doing more at 60-65 today. At 50-55 it vibrated in the past, but not today.

 

[pontiacgp]

check your rear axles to see if the axle bearing has caused a groove in an axle, also check to see if the pinion seal is leaking on the rear, that is an indication a problem with the bearing

 

[Streetbu]

Definitely coming from the rear of the car, I can see the trunk lid shake violently when driving. Odd thing is, it’s doing more at 60-65 today. At 50-55 it vibrated in the past, but not today.

If the trunk lid is shaking I kinda doubt it's a driveshaft issue. Sounds more violent. To me it sounds like a bent wheel, severely out of balance tire, bent axle shaft or something like that. Start at the basics. Take the the rear wheels off and go get them balanced. Tell them your fighting a vibration and ask if they see anything wrong with them when they are on the balancer.