Front end diving...

@NorthernMechanic

 

How do your springs look? No broken leaves or worn out spring pins? Any unusual tire wear? Shocks tight and not leaking? U-bolts tight?

 

Thanks @NorthernMechanic ...I knew you would have some input

 

Last time I had an issue like that was the leaf spring. I hit a pot hole on i80 and I thought nothing of it until I started to slow down and the truck started diving and clinging. Sure enough when I checked it throughly the leaf spring snapped.

 

I would lean toward NM and SMD's replies. However many years ago worked at a fleet that had 9670's with automatic slacks. Some times the slacks would have the adjustment toward the outer limits and do crazy stuff like that. If the adjustment was tightened up a little it would temporarily stop. Adjusting the clevis on the rod would correct it but they were always worse when stopping in reverse.

 

dry cam bushings will do that, bent shoes i have seen, spend the money and buy top quality shoes and drums, they more than pay for themselves in the long run. hammer down, go make that dollar!