PIE0676

Subject:
Engineering Information – Engine Coolant Reservoir Being Overfilled with Discolored Coolant, Shudder, Shake,
Vibration, Harsh Shift, Delayed Shift and/or Slipping Transmission Performance
Attention:
Proceed with this EI 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 PIE and proceed with diagnostics found in published
service information. THIS IS NOT A RECALL – refer to the latest version of Service Bulletin 04-00-89-053 for more
details on the use of Engineering Information bulletins.
Brand:
Cadillac
Model:
Model Year:
VIN:
Engine:
Transmission:
LSY
MHS, M5N
from
to
from
to
2020
2022
—
—
CT6
2019
2020
Escalade
Models
2021
2022
LM2
MQC
Silverado 1500
(New Model)
2019
2019
LM2, L3B
MQE, MQB, MQC
Silverado 1500
2020
2021
Silverado 1500
LTD (RPO J21,
12th VIN Digit =
4 or less)
2022
2022
LM2
MQC
LM2, L3B
MQE, MQB, MQC
LM2
MQC
CT4
CT5
Chevrolet
MHS
Silverado 1500
New (RPO J22,
12th VIN Digit =
5 or greater)
Suburban
2021
Tahoe
GMC
Sierra 1500
(New Model)
2019
2019
Sierra 1500
2020
2021
Sierra 1500
Limited (RPO
J21, 12th VIN
Digit = 4 or less)
2022
2022
Sierra 1500 New
(RPO J22, 12th
VIN Digit = 5 or
greater)
Yukon Models
2021
1
Involved Region or Country
North America
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 having one of the following conditions:
•
Engine coolant reservoir being overfilled/underfilled with discolored coolant and poor transmission
performance with any of the following symptoms: shudder, shake, vibration, harsh shift, delayed shift or
slip
•
Engine coolant or transmission fluid leak under the vehicle. There may or may not be any engine or
transmission performance issues report beside the external leak.
These conditions may be caused by:
Cause
•
Internal Leak: The Automatic Transmission Heat Exchanger may be experiencing an internal leak allowing
engine coolant and automatic transmission fluid to intermix.
•
External Leak: The Automatic Transmission Heat Exchanger may be experiencing an external and internal
leak allowing engine coolant and transmission fluid to intermix.
Correction
If you encounter a vehicle with the above concern, inspect the engine coolant reservoir for possible engine coolant and automatic transmission fluid intermixing. If
intermixing is suspected, the transmission fluid should be checked for evidence of glycol before contacting engineering. Refer to latest version of Service Bulletin #
08-07-30-035 (Information on Water or Ethylene Glycol in Transmission Fluid) in SI.
Contact Information
The Contact Information has been redacted.
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
8486108*
Engineering Information - Shake, Vibration, Harsh Shift, Delayed Shift, Slipping
Transmission Performance
0.3 hr
*This is a unique Labor Operation for bulletin use only.
Version
1
Modified
Released January 24, 2022
2