Balancing issues

[mconstant81]

I took my car to a dealership to get a shaking problem fixed between 45 - 55 miles per hour. They found balance issues after driving the car at high speeds. So they fixed it. They said one tire was out .036 so they balanced it and put it in the back of the car. Everything was going fine until I went on the highway and went about 75mphs. Then it started to shake again but it felt like it was coming more from the back. Now the car vibrates more and shakes at different speeds. And when the road is rougher I feel it a lot more.

My questions are if cars are balanced and I drive at a higher speed could that "un"balance them if there was something truely wrong with the steel wheels? I checked and the weights were still on them.

Can out of balance tires make a rough road feel a lot worse?

[chronoti]

yes, rub your hand over the tires and feel for bumps or air pockets they are easier to find when hot, because if you find one go get a new tire right away

[Hajoca]

Tire balancing machine spins the tire and weights corrects the balance for that range of speed. so it is possible that machine did not balance to 75 mph.

It will not correct a deformed and out of round tire.
Some tire balancers have a rolling load bar that will detect out of round tires and vibration under load.
Did the mechanic check for uneven wear on the tire tread?

[73sport]

What they said is true! ^^

IME, drivetrain vibrations induced by CV's, bearings, ect start at 45mph. That's not to say you have an issue with CV or anything as you said it comes from the rear. That implies a bad tire. If the tires have good deal of tread and can not be replaced under warranty or anything like that, you may opt for a speed shop that does dynamic On-car wheel balancing.

[mconstant81]

The issues happened even with old tires. I had shaking happening at 45 - 50. Replace the tires and still had the issue. Had the front driver side axle replaced. Still had the issue.
So I got the car balanced and they said that there was an issue with the balance at high speeds. So they fixed it. Then once I went fast it seemed to cause issues again.
So the tires are almost brand new but like I mentioned I did have issues before with the old tires.
I am just wondering if it is possible that my steel rims not my tires are at fault. I am very close to just trading this car in or selling it. Just seems like I have tried everything for such a small problem.
The only thing I haven't tried is replacing the steel wheels.

[73sport]

I'd take it to a shop, have them go for a ride along with you. Let them experience the shake. Tell them you'll pay to have it fixed. If they can't isolate, then no $$$$ changes hands.


Are the wheels bent?
Do the wheels/tire show runnout either lateral or side to side?
Was the car ever wrecked? It could have bent hub making any good wheel shake. Check for runout on the car.
How many miles on this car?
Engine? Trans? Shocks?
When is the last time it was aligned?


Is there someene in the family you could trade tires with?

[chronoti]

can you jack up the back end grab a tire and try to shake it to see if there is any extra play (shaking) might be a bad hub bearing or connecting rod.