File in Section:

Service Bulletin

Bulletin No.:
Date:

PIE0240
January, 2013

PRELIMINARY INFORMATION
Subject:

Engineering Information – Transmission Shift Concerns

Models:

2012-2013 Chevrolet Silverado
2012-2013 GMC Sierra
Equipped with Allison® LCT 1000 Automatic Transmission (RPO MW7)

Attention: Proceed with this PI ONLY if the customer has commented about this concern AND the
PIE number is listed in the Global Warranty Management / Investigate History link
(GWM/IVH). If the customer has not commented about this condition or the EI does not
show in GWM/IVH, disregard the PI and proceed with diagnostics found in published
service information. THIS IS NOT A RECALL – refer to Service Bulletin 04-00-89-053E
for more details on the use of Engineering Information PIs.

Condition
Important: If the customer did not bring their vehicle in for this concern, DO NOT proceed with this EI.
Some customers may comment on any of the following transmission shift concerns:
• Transmission would not shift out of low.
• Transmission will not upshift after first start-up.
• Intermittent late 1-2 upshift.
• Transmission takes long time to shift out of first gear.
• Transmission does not want to upshift at times (approximately 3500 RPM before it does).
• Transmission stays in first sometimes.
When checking the vehicle for DTCs, none may be present.

Cause
GM Engineering is attempting to determine the root cause of the above condition. Engineering has a need to gather
information on vehicles PRIOR to repair that may exhibit this condition. As a result, this information will be used to
"root cause" the customer's concern and develop/validate a field fix.

Instructions
Complete the following steps and contact the engineer listed below with your findings. The engineer will provide
further instructions.
1. Using a scan tool, check for diagnostic trouble codes (DTC).
2. From the Trans Data screen of the scan tool, log the following:
• SS1, SS2 and SS3 Valve Modulation counts
• Pressure Switch Dropout counts
3. Attempt to duplicate the concern by doing launches at various throttles.
4. Attempt to duplicate the concern by going to Reverse then Drive after an ignition cycle. It has been reported that
the condition occurs after the first shift of an ignition cycle.
5. Capture a snapshot of the events with a scan tool.

Contact Information
Engineer Name

Phone Number

Brett Caldwell

317-697-0519

Scott Mundy

317-697-5596

Please include the following information if leaving a message:
– Technician name
– Dealer name and phone number
– Complete VIN and repair order (R.O) number
On the repair order, document the date and time the call was placed (even if the engineer was not reached).
If engineering is unable to return the call within one hour, proceed with diagnosis and repair based on information
found in SI.

Warranty Information
If engineer was contacted or required information was provided, use:
Labor Operation

Description

Labor Time

K9564*

Engineering Information – Transmission Shift Concerns

0.8 hr

*This is a unique labor operation for bulletin use only. It will not be published in the Labor Time Guide.