Toyota Tacoma Load Sensing Proportioning and By-Pass Valve (LSP & BV) Inspection Guide

Quick guide from the manual

This document provides the official procedure for inspecting and adjusting the Load Sensing Proportioning and By-Pass Valve (LSP & BV) on 2003 Toyota Tacoma vehicles. The process involves setting the rear axle load, installing a pressure gauge, and verifying rear brake pressure against front brake pressure specifications.

Inspection Procedure

1. Set Rear Axle Load: Ensure the vehicle is loaded to the specified weight (700 kg for 2WD except Pre Runner; 850 kg for 4WD and Pre Runner).
2. Install Gauge: Use the SST 09709–29018 to connect a pressure gauge and bleed the air from the system.
3. Check Pressure: Raise front brake pressure to 7,845 kPa (1,138 psi) and measure the resulting rear brake pressure.

Fluid Pressure Adjustment

If the rear brake pressure is incorrect, follow these steps:

• Adjust No. 2 Shackle: Lengthen the shackle to decrease pressure or shorten it to increase pressure.
• Valve Body Adjustment: If shackle adjustment is insufficient, raise or lower the valve body (Lower body for low pressure; Raise body for high pressure).
• Torque: Tighten the nuts to 13 N·m (130 kgf·cm, 9 ft·lbf).

Valve Body Check

If pressure remains incorrect, assemble the valve body in the uppermost position and perform a final pressure check against the provided standard tables. If values are still outside the standard, the valve body must be replaced.