| Subject: | Flare and Or Harsh 2-3 Shifts |
| Models: | 2007-2008 Cadillac Escalade, Escalade ESV, Escalade EXT, STS-V, XLR |
| 2006-2008 Chevrolet Corvette |
| 2007-2008 Chevrolet Silverado |
| 2007-2008 GMC Sierra Denali, Yukon Denali, Yukon Denali XL |
| Equipped with 6L80 (RPO MYC) or 6L90 (RPO MYD) Automatic Transmission |
The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.
Condition/Concern:
Some customers may comment on a flare or harsh 2-3 shift.
Recommendation/Instructions:
This condition may be caused by leaking 1-2-3-4 and 3-5-R clutch fluid seal rings (230). The following conditions are indications that the fluid seal rings may be leaking:
| • | Delayed/extended or delayed with harsh feel initial Park to Drive and/or Reverse to Drive shifts, that are more likely to occur when the transmission temperature is below approximately 40 degree C (104 degree F).
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| • | Harsh or flaring 2-3 shifts that are more likely to occur when the transmission fluid temperature is in the approximately 0 degree C (32 degree F) to 40 degree C (104 degree F) temperature range, but can be present at any temperature.
|
| • | Harsh 2-3 shifts that are more likely to occur at less than 50% tp.
|
Vehicles built in the January through August, 2007 time frame are more likely to have leaking fluid seal rings.
Important: When inspecting the 1-2-3-4 and 3-5-R clutch fluid seal rings (230) there probably will not be visible signs that the seal rings are damaged.
If any of the conditions above describe the flare/harsh 2-3 shift condition replace the 1-2-3-4 and 3-5-R clutch fluid seal rings (230), DO NOT replace the valve body or TCM.
Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.
