Description
Quality replacement service gladhand for tractor, trailer and dolly air brake systems. The Midland Industries 39512 is an angle-mount blue service coupler with a powder-coated aluminum body, a black rubber full-face seal and two 3/8 in female pipe ports, and it meets SAE J318. It handles the service (control) line that pressurizes on brake application, and pairs with a red emergency gladhand such as the Midland 39511.
Signs You Need a New Gladhand
- Audible hiss at the coupling with the trailer connected, most noticeable when the service brake is applied
- Slow air buildup, compressor cycling too often, or the low-air warning light and buzzer triggering
- Weak, delayed or uneven trailer braking as the service line fails to deliver full signal pressure
- Gladhands popping apart under road vibration from a worn cam lock face or damaged wear plate
- Cracked or corroded body, or a cut, dry-rotted or blown-out seal drawing moisture and debris into trailer valves
Specifications
| Manufacturer | Midland Industries |
|---|---|
| Part Number | 39512 |
| Part Type | Angle Mount Service Gladhand |
| Engine Compatibility | Universal air brake systems, not engine-specific |
| Line | Service (control) — Blue |
| Mount Style | Angle / bracket mount |
| Ports | (2) 3/8 in FPT — second port ships plugged |
| Body Material | Powder-coated aluminum |
| Seal | Black rubber, full face |
| Filter Screen | None |
| Mounting Holes | (2) at 11/32 in diameter |
| Standard | Meets SAE J318 |
| Weight | 1.36 lb |
Cross References
This part replaces or is equivalent to the following part numbers:
- Phillips: 12-136
- Haldex: 11440
- OTR: OTR11440
- Tectran: 9217
- Velvac: 035092
- Grote: 81-0001-38B
- Tramec Sloan: F36161 (includes filter screen)
- Tramec Sloan: 441023
Applications
This gladhand fits the service line on any air-braked vehicle using a bracket-mount coupler, including:
- Tractors, trailers and converter dollies built to FMVSS 121
- Trailer nose mounting locations that accept a direct-bolt angle gladhand
- Any system using 3/8 in NPT service line connections
Verify mounting style and port thread against the gladhand being replaced before ordering. This is the blue service coupler — the red emergency side is a separate part. Gladhands couple by a standardized SAE J318 interface, so fitment is by mount and thread rather than truck make, model or year.
