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Leveling Valves | Trailer ABS | Hose, Fittings, Misc.
Leveling Valves | Trailer ABS | Hose, Fittings, Misc.
Trailer Valves
Below on this page you will find a list of the Haldex trailer air valves that are currently in stock.
The first step to understanding how to maintain air valves is to identify your configuration. Haldex offers comprehensive charts that show typical configurations and provide recommendations for typical problems. You can view these charts best by zooming in and scrolling around to see the components and recommended maintenance.
The first step to understanding how to maintain air valves is to identify your configuration. Haldex offers comprehensive charts that show typical configurations and provide recommendations for typical problems. You can view these charts best by zooming in and scrolling around to see the components and recommended maintenance.
Haldex Guides for Identifying Air Brake Configurations & Troubleshooting
Spring Brake Valves
Haldex FF2 Full Function Valve
Our biggest selling valve combines 4 service brake ports with 2 spring brake control ports for those trailers that do not require ABS. Available new and re-manufactured. Used with single or twin air tanks. When upgrading an existing system you will replace both the relay and spring brake valves.
Haldex Full Function valve used with two reservoirs.
RT4 Multi-function trailer (spring brake) valve
- Used on trailers to control parking and emergency functions. Complies with FMVSS-121 to apply brakes upon loss of trailer supply pressure. Specifications for the RT4 trailer valve can be found here.
- Combined with the RT4 valve the 2 port RG2 trailer valve can also be used by trailers that do not require ABS. For port sizes and control port angle see specs for the RG2 here.
Typical RT4 Multi-function valve configuration
Other Helpful Info
about Spring Brake Valves
Haldex Trailer Valves Currently In Stock
| |
| Trailer | Spring brake valves |
| FF2 Full function service relay w. 2 spring brake controls |
| | KN28600 |
| | new, OE N4304AC; crack pressure 3 psi |
| | spring brake ports 3/8"; reservoir 3/4"; control 1/4" |
| | 4 delivery ports 3/8"; supply 3/8" |
| | KN28601 |
| | OE pn N4304AB; crack pressure 3 psi |
| | spring brake ports 3/8"; reservoir 1/2"; control 1/4" |
| | 4 delivery ports 3/8"; supply 3/8" |
| | KN28601X |
| | OE pn N4304AB; crack pressure 3 psi |
| | spring brake ports 3/8"; reservoir 1/2"; control 1/4" |
| | 4 delivery ports 3/8"; supply 3/8" |
| RT4 Multi function spring brake valve |
| | KN26000X |
| | reman, 2 supply pts 3/8"; 1 control 3/8"; 4 delivery ports 3/8" |
| | reservoir ports 1/2. 3/8", 55 psi PPV closing |
| | KN26020 |
| | new, supply pt 3/8"; control pt 3/8"; 4 delivery ports 3/8" |
| | reservoir ports 1/2. 3/8", OE N4305A; 70 psi PPV closing; |
| | PPV Closing pressure |
| |
| Trailer | Relay valves |
| RG2 2 port relay valve for tractor/trailer compares to Bendix R-12 |
| | KN28500X |
| | reman, 2 del. pts 3/8", 1/4" contrl pt, 2 suply pts 3/8", 5.6 crk |
| | KN28510X |
| | reman, 2 del. pts 3/8", 1/4" contrl pt, 2 suply pts 3/8" & 1/2" |
| | KN28520 |
| | new, 2 del. pts 1/2", 1/4" contrl pt, 2 suply pts 1/2", 5.6 crk |
| | KN28520X |
| | reman, 2 del. pts 1/2", 1/4" contrl pt, 2 suply pts 1/2", 5.6 crk |
| 2 Port with Integral Bracket for truck/trailer |
| | KN28060X |
| | reman, truck/trailer OE N30096L; crack pressure 4.6 +/- 1.5 psi |
| | 2 supply ports 1/2"; 2 delivery ports 3/8"; 1 control port 3/8" |
| | KN28061X |
| | reman, truck/trailer OE N30096L; crack pressure 4.6 +/- 1.5 psi |
| | 2 supply ports 1/2"; 2 delivery ports 1/2"; 1 control port 3/8" |
| 2 Port without Anti-Compounding - dual control for truck/trailer |
| | KN28065X |
| | reman, crack pressure 4.6 +/- 1 psi; oe N30100AR; with bracket |
| | 2 supply pts 1/2"; 2 delivery pts 1/2"; 2 control pts 1/4" |
| 2 ports for truck/trailer service brakes includes bracket |
| | KN28131X |
| | reman, OE N30106F; crack pressure 4.6 +/- 1 psi; no bracket |
| | 2 delivery pts 1/2"; 2 supply pts 1/2"; 1 control pt 1/4" |
| 4 Port with Integral Bracket for truck/trailer |
| | KN28085X |
| | reman, OE N30096P; crack pressure 4.6 +/- 1.5 psi |
| | 2 supply pts 1/2"; 4 delivery pts 3/8"; 1 control pt 3/8" |
| Emergency relay valve for pre-121 trailers |
| | KN30300X |
| | reman, 2 delivery pts 1/4", 1 control pt 1/4", crack 3.0 psi |
Haldex Relay Valves - when ABS not required
Trucks and trailers manufactured since 1997-98 are required to use ABS valves for controlling service brakes and a separate relay valve is not required with trailer ABS systems. Haldex continues to offer a wide variety of standard relay valves with 2 and 4 delivery ports, 1-2 control ports, a built-in two-way check valve for anti-compounding, and dual crack pressures. Several of the valves that we have in stock can be used for either truck or trailer.
Prior to new FMVSS 121 regulations in 1992, in the absence of spring brakes, relay valves were used to apply brakes in emergencies. Those older valves continue in production and are stocked by Plaza. See the piping diagram using pn KV300300X below.
Prior to new FMVSS 121 regulations in 1992, in the absence of spring brakes, relay valves were used to apply brakes in emergencies. Those older valves continue in production and are stocked by Plaza. See the piping diagram using pn KV300300X below.
Typical valve configuration prior to FMVSS 121 using relay emergency valve KN30300X
