I have an intermittent problem with my truck shaking. It is a 1990 Suburban 5.7 engine, auto trans, 4x4 280,000 miles. When I am driving the truck and am just cruising(not accelerating or decelerating) the rearend of my truck gets a terrible shake in it. I thought it was the transmission but I have been driving witht the trans in drive and overdrive and I still have the problem. It is not the tires and wheels because the problem is not all the time.

Any help would be great.

Thanks
Joe

 

With that many miles, I'd pull the cover off the differential look for gear problems. I have a 2000 that was noisey, it turned out to be the planet gears, was easy fix at that point.

 

Greetings joey welcome to the Forum !

I just can't help but think it's a Balance or Alignment problem.

Check both again, and maybe you can find someone who can use
one of the older Balancers, which really spin um up high.

It could be an issue, where your tires need to be "together"
in a certain place, before they shake. You might try stopping
and turning or in circle, just to get the tires out of the location
that they were in compared to the other.

If you have some good Jack Stands, you might try getting the
rear end up off the ground, and running it while you watch close.

So ok, I'm just guessing here HA, but it just has to be one of
those two things.

Good Luck

 

I have a 2003 Suburban and went through a load of attempted fixes before I finally got rid of the back-end vibration I was experiencing.

Like mine, I think yours could be the Prop shaft U joints are worn - you experience the most vibration when running at high speed under light load - I had mine replaced and it cleared up about 80% of the vibration.

The other 20% my Chevy dealer found was due to a road force issue with the budget back tires I had on the truck. I had had them balanced multiple times and they looked perfect on a normal balancer - however when I had them roadforce balanced by my tire shop - both tires failed and they replaced them under the tire warantee. The truck now runs perfectly with zero vibration.

 

I'm wondering if I have the same issue. The truck has a load booming vibration over 40 MPH that seems to disappear at 50MPH. Did yours do something like that before the u-joints were changed?

 

My vibration is at any speed up to 70 and down to 35. I am going to send my driveshaft out for balance next.

 

could be the tires.

what name brand, size, tread pattern do you have? Try rotating them around.