Peterbilt bouncing problem!!!

Only thing left is Kingpins and leveler valves.

 

General rule of thumb: front end problem is felt in the steering wheel & rear of truck/drive shaft comes up through the seat. I had a W9 with a bad vibration that was not noticeable in the steering wheel but it sure did shake the truck. Turned out to be a steer tire with a couple of dips in the outer rib. To me they did not appear to be big enough to cause the shaking I had. I could let go of the steering wheel and the truck would go straight down the road without any wobble in the steering wheel. Removed that tire - no more shake. Go figure

 

I had the same problem. The bounce would come and go. I even had my mechanic ride beside my truck in his car and could see the rear end bouncing. I did have a 3 axle alignment done 3 times. It wasn't until my mechanic asked if they used a torch to align the rear. I said no and was totally confused. He told me where to go. It took me 2 weeks before my appointment. They had to use a torch to take the nuts off the rear and put shims in. One axle was pointing one way and the other pointing the other way. My front was way out also. That solved ALL my tire problems and bounce.

The alignment was done at FleetPride in Londonderry, NH by an old timer. He's been there forever and that's all he does there. He told me my truck was never aligned properly since there were no shims anywhere on the truck. They use one big ### air wrench there.

 

it's the kingpin.. hook to a newer trailer, and it will ride like a new bounce free sexy beast

 

What did you ever find out what it was

 

Did you ever figure out the problem? I’m having the same exact bounce.

 

I had the same problem what I did was let some air out of my tires. Everything else was replaced front end, bushings ,kingpins, everything beforehand. It wasn't perfect but it cured most of the shake and the bounce. Too much air can cause you to feel the road excessively. So just try putting less than the recommended PSI on steer tires.