Nissan Stanza/200SX/240SX 1982-1992 Repair Guide

Brake Proportioning Valve


All Datsun/Nissans covered in this guide are equipped with brake proportioning valves of several different types. The valves all do the same job, which is to separate the front and rear brake lines, allowing them to function independently, and preventing the rear brakes from locking before the front brakes. Damage, such as brake line leakage, in either the front or rear brake system will not affect the normal operation of the unaffected system. If, in the event of a panic stop, the rear brakes lock up before the front brakes, it could mean the proportioning valve is defective. In that case, replace the entire proportioning valve.


See Figures 1, 2 and 3

Models built in 1985 and later years do not use a separate proportioning valve.

  1. Disconnect and plug the brake lines at the valve.
  3. Unscrew the mounting bolt(s) and remove the valve.

Do not disassemble the valve.

  1. Installation is in the reverse order of removal. Bleed the complete brake system.

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Fig. Fig. 1: Proportioning valve-Stanza

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Fig. Fig. 2: Cross section of proportioning valve-most models similar

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Fig. Fig. 3: Bleeding the brakes