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For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 1999 🢒 Chevy P12 Chassis 🢒 Transmission/Transaxle 🢒 Automatic Transmission - Allison 🢒 Low Main Pressure in First Gear

Low Main Pressure in First Gear for Chevrolet Chevy P12 Chassis 1999

Possible Cause

Action

The first range circuit is leaking in the control valve body.

Replace or rebuild the control valve body.

The first clutch piston seals are leaking excessively.
  1. Overhaul the transmission.
  2. Refer to applicable Allison Transmission Service Manual.
  3. Replace the seals.

Refer to applicable Allision Transmission Service Manual.