Front End Vibration

[Ugly3]

I have a 98 Chrysler T&C with 150,000 miles on it. Ran 80,000 miles on a set of tires and had no vibration of any kind.

Because of mileage I had new struts installed and new brakes installed as well as new tires. I now can go 60 MPH with no vibration, above 60 MPH and the steering wheel starts to shake. I had the tires rebalanced on a Hunter GSP7200 machine (puts 1200# load on the tire while balancing) - the tires and wheels are "perfect".

Recently on a road trip I was going 60 MPH and all of a sudden it felt like I was riding on the rumble strip on the side of the road. I stopped, looked things over (looked OK) and kept going but at 50 MPH. The "rumble" continued for 20 miles then stopped. Returned to 60 MPH and was smooth as glass.

I think the over 60 MPH vibration is caused by the new rotors being out of balance. I think the "rumble" is the axle half shafts about to go out.

Any thoughts will be appreciated.

 

[outrun]

Take it to a respectable dealer or an experianced front end shop for a full suspension-steering evaluation.

Also photo copy all your previous suspension-front end work orders so the techs will have some idea of previous repairs.

The key with these hard to figure out problems is to find a good and honest tech/shop.

It is easy to find idiot techs/shops, its a goldmine to fine the excellent and experianced. ones :

 

[Gary Allan]

Motor mounts? This will cause the short side axle to wobble. Any clunking on startup or coming to a stop? The "hub" would be another thing that I'd investigate. It usually doesn't show up like that however. It usually shows up as tire wear.

 

[seotaji]

my axles are going and it shakes when accelerating to highway speeds.

quote:

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I think the over 60 MPH vibration is caused by the new rotors being out of balance

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you mean warped or uneven?

i'd check the axles for too much play just to make sure.

 

[Ugly3]

Outrun -

Here is the part that just drives me crazy. Before I had the front end worked on it was just fine, just had a lot of miles on it. Now, with TLC and new parts I get a vibration - the world just ain't fair.

Never had any work done on the front end except sway bar bushings (they were really banging) and the links between the sway bar and the struts were replaced.

After that I had the struts replaced, new brakes and rotors (Chrysler rotors). The shop said the front end was tight (ball joints and tie rod ends) and that the axle shafts were just fine.

At the same time I replaced the rear shocks (the big ones required for rear ABS), only available from the dealer for real $$.

I know the shop I am using is an honest shop but they are not front end specialists. The owner is a friend of mine for 30 years, he wants to get the problem solved too but doesn't know what to do next.

I will continue to look for the "experienced" and honest front end shop - thanks for your reply.

 

[Ugly3]

Gary Allen -

The motor mounts are a possibility, never thought of that. Thanks.

The previous tires were on for 80,000, never rotated, and the fronts were way better than the rears. The rear tires had more rubbor on them but were not wearing as even as the fronts. So I doubt the hubs are the culprit.

No clunking on starts or stops. Like a church mouse!

Thanks for the reply.

 

[Ugly3]

Seotaji -

you asked:

you mean warped or uneven?

The rotors work fine a s a brake part, no pedal pulse, no fade, no nothing.

I am guessing they may be heavier on one side than the other causing a higher speed vibration while going down the hiway. The tires and wheels are balanced and the only remainig part that spins is the rotor and it was not balanced with the wheel and tire assembly.

I am considering jacking up the front end and running the Van up to about 100 MPH to see which side if any is vibrating. I think I have to keep the brake on slightly to keep the pressure on the alex shafts.

Anyone have any experience with such a retard procedure?

 

[theguru]

Don't do it unless you want to seriously hurt or kill someone, possibly including yourself.

 

[seotaji]

Don't do it.
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I would think that if one side of the rotor is heavier than the other, it would show up as a uneven part (thicker) where a micrometer would be able to tell. Or just get some new rotors and see if that fixes it?

A lot of times, rotors are shipped from china stacked high and that usually affects the ones on the bottom. Could be that they installed a faulty part.

 

[Ugly3]

Got the problem fixed!

It was the axel shafts, replaced both sides and it is as smooth as a kitten at all speeds.

 

[seotaji]

quote:

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i'd check the axles for too much play just to make sure.

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HA i was finally right!

actually, i had this same problem and just had the axles replaced.