BPR1 TYPE PROPORTIONING VALVE 4.0PSI

Name: 170.065145 - BPR1 TYPE PROPORTIONING VALVE 4.0PSI
Brand: Automann
SKU: 170.065145
Price: 57.15 USD
Availability: InStock

This is a BPR1-type bobtail proportioning relay valve for heavy-duty truck air brake systems. It combines a standard relay valve (lower section) with a proportioning valve (upper section) to automatically reduce air pressure to the rear brakes when the tractor is operating without a trailer (bobtail mode). By lowering rear brake force, it prevents wheel lockup and improves stability and control during solo tractor operation. The valve opens at a crack pressure of 4.0 PSI and is replaced when it fails to properly modulate pressure, causing uneven braking or rear wheel lockup while bobtailing.

$57.15

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Verified fitment

Heavy-duty tractors operating without a trailer (bobtail mode)
Class 8 air brake systems requiring bobtail proportioning

Designed for any heavy-duty tractor with air brakes that needs bobtail brake modulation; verify port sizes (1/2" NPT supply, 3/8" NPT delivery, 1/8" NPT control, 1/4" NPT service) and crack pressure match OEM specification.

Specifications

SKU170.065145BrandAutomannSupplierPost OnsiteCategoryBrakes & Wheel EndAvailabilityIn StockCrack Pressure4.0 PSISupply Port1/2" NPTDelivery Ports2 × 3/8" FPT (side), 2 × 3/8" FPT (bottom)Control Port1/8" NPTService Port1/4" NPTActuationAirMaterialAluminum housingMountingFrame mount with bracket (5/16" mounting holes)