Trailer "jumps/hops/skids" When Braking Empty/Light Load

Has anyone off you ever put a pressure gauge on their problem trailer?

 

I'm taking it into the shop tomorrow, I'll keep you guys posted on what the problem is!

 

I did. everything was within specs.

 

Doesn't air ride have shocks??? Never seen one that didn't. Seems no shocks on air ride suspension would make for a brutally bouncy ride? Please correct me if I'm wrong!

 

It is a newer design off airbag.
I read about it a while back.

 

Hendrickson - ZMD - Zero Maintenance Damping

 

Put a 2x4, pipe or piece of dunnage up against the tire treads and try to lever them around. If you can shove an axle fore or aft look closely at the trail arm bushings.

Also, were all the drums definitely replaced with new? Or was a few changed, a few left old and all the slacks tightened up?

A warped old drum with tight adjustment will grab on the "high spot" so to speak and that torque is transmitted into raising the trailer.

 

Get the abs checked, this almost always happens when I pull a trailer with a faulty ABS. It feels like the brakes pulse when you hit them. Especially dangerous when your loaded and need to stop quick and your brakes are only at half power.

 

Thanks for everyone's suggestions! It turned out being the valve. The shop replaced valve again, and put oem in this time! I guess oem is the only way to go for air valves and abs equipment!