September 30, 2005
Anatomy of a Transmission: Oil Flow in the Pump-PR-Converter-Cooler Lube Circuits
Gregg Nader
Symptoms:
- Code P0872
- Code P1711
- Pressure switch stuck on
- Failsafe mode
- 3rd Gear starts
Cause:
Deterioration of the E-shift bore causes valve sticking that leads to trouble codes and drivability concerns.Correction:
Stop valve hangup and restore normal operation by reconditioning the bore and installing Sonnax oversized E-shift valve kit.Warning:
Required tool kit F-37000-TL15 is no longer in production. Check with your distributor for availability.
1000/2000/2400
Oversized E-Shift Valve Kit
Part No. 37000-15K
Fits '00–'09 units only.
-
Tooling:
- F-37000-TL15
- VB-FIX
You need this if... View Instructions Find a Distributor
GM trucks equipped with Allison® 1000/2000/2400 transmissions often go into failsafe mode with codes P1711 or P0872 set in computer memory. This can be caused by bore wear at the E-shift valve, which allows the valve to hang up in the bore. Reconditioning the bore and installing Sonnax oversized E-shift valve kit 37000-15K restores normal operation by renewing critical clearances to allow smooth valve movement and the hardcoat anodized aluminum valve combats premature wear.
- Spring
- Valve
- End Plug
Sonnax valve body layouts provide a detailed overview of individual units making it quick and easy to determine what’s available for the specific valve body you’re working on. See all Sonnax valve body layouts.
GM Allison® 1000/2000/2400 Valve Body Layout
February 08, 2017
Identifying Allison 1000/2000/2400 Valve Bodies
August 01, 2019
Allison 1000/2000/2400 Vacuum Test Guide
You need this if...
Vacuum testing at the port(s) indicated fails to hold the recommended minimum in-Hg, or if wear is visually detected.
