Shaking under acceleration

[todras]

I thought it was the tires possibly out of balance. So I had them balanced. Then I realized that it was only happening when I put my foot on the pedal at highway speeds. 60+ Is this a motor mount problem?

 

[Bizzy]

What shape are the tires themselves in? Are they worn or is there any cupping?

It could be a combination of several problems. Tires to start with and alignment. These problems can be amplified by loose or worn front end components like inner and outer tie rods, etc.

Edit: I don't think it's a motor mount problem. You'll notice a good bit of torque steer when you first start to move and motor movement (forward or backward rocking) with a bad mount.

<small>[ August 05, 2003, 02:20 PM: Message edited by: Bizzy ]</small>

 

[todras]

Tires are in excellent shape. They are a size taller than stock though. Previous owner must have thought he wanted a more cushy ride. frown

 

[todras]

Car tracks straight as an arrow BTW. Doesn't mean the alignment isn't off I guess. Tires are wearing normal. The vibration has gotten worse over time.

 

[sdpatt]

What is shaking?

 

[todras]

Entire car.

 

[Huntervf]

Ball joints, tie rod ends, bushings...our cars wear out front end items in the worst way. Odds are something is worn out & causing the shake at higher speeds, or you could just have a bad rim. We've also had vehicles at the dealership with a similar shake...even though the tire balances out you can still have a shake at higher speeds if you have a bad rim or even bad tires.

 

[todras]

I know what it could be but wouldn't it more obvious since it only vibrates when the engine is under load? Defective tires would vibrate all the time. Like if I'm going 70 and let off the gas the vibration stops. shrug

 

[SHO_Driver]

Could be a driveshaft with a worn inner joint. Usually the outer joint wears causing a knocking noise on turns. When the inner joint wears you could get a steady vibration when accelerating, especially at higher speeds.

 

[shojuan]

Inner joint wear is extremely rare unless the boots have torn. And inner boots don't tear very often.

I would suspect all the wearable suspension components first. A wheel bearing might be on its way out. Anything that allows dynamic toe or camber changes while driving down the road isn't going to be too good for the ride either. How old are those tie rods? Are your strut mounts or ball joints worn?

 

[todras]

When my dad had the car for a little while he had a Midas Shop replace one of the boots that I discovered ripped. Wonder if they reinstalled everything correctly. Maybe the boot had been ripped too long and caused damage. I've heard CV's go and this isn't it. No clicky turning. It will get a singe clunk when taking off from a start now and then. Every 3 days I'll hear it.