Vibration at 70 mph

[fisher60]

This vibration started about 6 months ago and is slowly getting worse. I had an alignment done and the front tires re-balanced. No improvement. Yesterday I replaced the front tires and still no improvement. Could this be coming from the rear wheels? How many of you re-balance the rear duals at periodic intervals? Mine are just over three years old and have never been off. Any suggestion is welcome

[j-d]

I had oscillation in a worn out Second Generation E-Series that my company had. I'll tell you explanation as I remember hearing it. The wheels spin as a gyroscope. Hit a bump and the force tries to push the wheels up. But as a gyro, the wheels try to go to the side. If anything is worn, they do. Now the wheels drop as the van rebounds. Gyro forces the wheels the other way. Slack in suspension parts...oscillation. I crossed a railroad track at 35 and had to come to nearly a full stop before it stopped.

[Bordercollie]

Had an oscillation in front wheels after hitting rough spot in road,slowed down and oscillation stopped. Reminded me of a shopping cart caster wobble. Had suspension etc checked by an RV service, nothing found, suspension was like new. Was told that my symptoms are fairly common with Ford E-450 front end.(?)

[DUNEBUGGYDOUG]

Just try slowing down a little bit .70 mph is a little fast IMHO.

[enblethen]

Have a good front-end shop check the control arm bushings and the ball joints.

[IAMICHABOD]

I see in your signature that yours is a 01 but there was a service bulletin for 2003 and newer but it may apply to earlier models too, might be worth looking into. the links in this thread may be helpful.


Steering problems

[fisher60]

enblethen wrote:
You added that you believe the vibration is in the steering wheel. That would not be consistent with drive line vibration.
Is the vibration side to side or is more like a bounce? Is it a rumbling sound?
How many miles are on the rig?
What chassis? Ford?
Has anyone checked the ball joints and control arm bushings.
Vibrations can be funny. You make think it is in one place and actually be some where else.

It's a Chevy chassis with 83k miles on it. I have not had any front end work done on it except for an alignment and brake job. The vibration is definetly a bounce. I know chasing these issues can be frustrating.

[fisher60]

dakdave wrote:
I would drive Motorhome a few miles on highway come back and immediately crawl under and lay a hand on each U-joint and hanger bearing looking for one or more that are warmer than others.
It sounds to me like you have one that is tight.

Dave

I will do that

[fisher60]

othertonka wrote:
Were the front tires spin balanced on the vehicle? that way you balance the whole system, brake drums/rotors, wheels and tires. Check for out of round tires/wheels.

No

[enblethen]

You added that you believe the vibration is in the steering wheel. That would not be consistent with drive line vibration.
Is the vibration side to side or is more like a bounce? Is it a rumbling sound?
How many miles are on the rig?
What chassis? Ford?
Has anyone checked the ball joints and control arm bushings.
Vibrations can be funny. You make think it is in one place and actually be some where else.

[dakdave]

I would drive Motorhome a few miles on highway come back and immediately crawl under and lay a hand on each U-joint and hanger bearing looking for one or more that are warmer than others.
It sounds to me like you have one that is tight.

Dave

[othertonka]

Were the front tires spin balanced on the vehicle? that way you balance the whole system, brake drums/rotors, wheels and tires. Check for out of round tires/wheels.

[fisher60]

othertonka wrote:
while you are under the rig check for bad U Joints also. yes rear tires can also be out of balance and cause vibration. If fronts are out you usually feel it in the steering wheel. If rears are out, you usually feel it in the seat of your pants.

This is definetly in the steering wheel

[othertonka]

while you are under the rig check for bad U Joints also. yes rear tires can also be out of balance and cause vibration. If fronts are out you usually feel it in the steering wheel. If rears are out, you usually feel it in the seat of your pants.

[fisher60]

enblethen wrote:
It could be the center drive line support bearing.

Hmmmm that's a thought. Going to drain & refill the differential here in a day or two and I'll take a look then. Thanks