PART NO : AB8474P                          
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The R-8P pressure equalizing pilot relay valve is a devicedesigned to reinforce the control signal on long wheel base towing trailers and converter dollies. Unlike a standard relay valve which typically has a 4 PSI crack pressure and similar differential between control and delivery, the R-8P valve has a 0 PSI differential. On the converter dolly and long wheel base towing trailers, the R-8P valve reinforces the service brake application signal without the differential found in standard relay valves.The 0 PSI differential of the R-8P valve assures that alltrailer and dolly brakes will receive the same strength control signal even during light brake applications. By providing a balanced pressure signal to all trailer and dolly brakes, the R-8P valve helps achieve overall vehicle brake balance and stability. The R-8P valve also helps improve brake lining wear balance on combination vehicles by causing even the most distant brake to contribute it's share of braking effort.

SUPPLY PORT:
3/4" NPT

DELIVERY PORTS:​
3 @ 1/2"

CONTROL PORT:​
1/4"

CRACK PRESSURE:
0 PSI

CROSS REFERENCES:
287114X, 107455, KN28300, R8P.
A cross reference listing means that this valve is a suitable replacement for the part numbers listed. Some changes in air line plumbing may be required.