Moog Overrun Damper for BPW/PEITZ PAV/SR 1.3-X - Replacement Drawbar Damper for Trailers
- Moog hydraulic overrun damper for the BPW/PEITZ PAV/SR 1.3-X overrun coupling. It smooths the drawbar movement so the trailer brakes work gently and without jerking.
The Moog overrun damper for BPW/PEITZ PAV/SR 1.3-X is a hydraulic damper that works in the trailer drawbar between the overrun coupling housing and the drawbar shaft with the coupling head. It smooths the drawbar movement when braking and pulling away, so the trailer brakes come on gently and the combination does not jerk.
How the overrun damper works
When the car brakes, the trailer pushes against the tow ball and the coupling shaft slides into the housing. Through the lever and the brake rod this movement applies the trailer wheel brakes. The damper slows the shaft moving in and out. Without it the brake would act in jerks, and the combination would snatch when pulling away and on bumps.
When to replace it
You can recognise a worn damper by knocking and jerking when braking, the trailer braking too hard when you slow down slightly, or oil leaks. A simple test: with the trailer parking brake applied, the shaft should push in with a clear, even resistance and return by itself. If it slides in without resistance or returns in jerks, the damper needs replacing.
- knocking and jerking when braking
- trailer brakes abruptly when you slow slightly
- oil traces on the piston rod
- shaft slides in without resistance
Fitment
The damper is matched to the BPW/PEITZ PAV/SR 1.3-X overrun coupling. Length, stroke and end fittings must match the original, otherwise the brake will not work correctly. You will find the coupling type on the plate on the housing.
Fitting
Uncouple the trailer from the car and secure it against rolling. Drive out or unscrew the fixings of the old damper, fit the new one in the same position and secure the joints with new sleeves or nuts if the old ones are worn. Take the chance to inspect the shaft bellows and the whole brake linkage. Brake and overrun parts have a direct effect on driving safety. If you have no experience repairing trailers, leave fitting and adjustment to a workshop. After any repair, check the brake on a short test drive.
Key data at a glance
| Feature | Value |
|---|---|
| Brand | Moog |
| Type | overrun damper (hydraulic) |
| Fits | BPW/PEITZ PAV/SR 1.3-X |
Questions and answers
How do I know the damper is worn?
By jerking and knocking when braking and by the coupling shaft sliding in without resistance.
Does it fit a coupling other than BPW/PEITZ PAV/SR 1.3-X?
Do not fit it without checking. Dampers for different couplings differ in length, stroke and fixings.
Can I replace it myself?
With basic technical skills yes, but it is part of the brake system. If in doubt, let a workshop do it.