2015 Peterbilt 579 Drive Wheel Shake

‘15 579. New Michelin drive tires. Four eight months ago and four two months ago. Prior to the last four I blamed the recaps but it is still there and worse than ever. What I’ve done: Centramatics!, 2 new balanced drums, centering bushings for all drums, sleeved centering lug nuts….2 on each wheel, removed tires…broke the bead then applied black tire grease to the rim and tire. I pull a flatbed and when I have a load like 20 foot steel bars where the load is concentrated toward the center of the trailer it is much worse. (Aluminum flatbed…like a big leaf spring) When the load is spread out like lumber the shake is barely noticeable. Empty or bobtail…..even less noticeable but still there. Any suggestions anyone?

 

All drums and wheels are running true as I put it on jackstands and run it to 75 mph. Bearings are tight. New shocks. This is not a vibration. It is exactly like an out-of-balance or out-of-round shake/shimmy. Like recaps usually do.