4T65-E Channel Plate Identification
Valve Body Xpress
| Valve Body Side | |
|---|---|
| GM Style | Volvo & GM Tap Shift Style |
 |  |
| Case Side | |
| Early Style (1 Blow-Off Ball) | Late Style (2 Blow Off Balls) |
 |  |
There are two worm track configurations on the valve body side of 4T65-E channel plates: GM Only style & Volvo/GM TAP shift style. There are two possible locations for pressure blow-off balls, along with their associated springs & retainers:
- The TCC blow-off ball is present on all models.
- The converter drain-back blow-off ball is only used on some channel plates.
On models with no drain-back ball, the pressure relief valve will instead be located in the return cooler line fitting. It is important not to put a channel plate with a drain-back ball on a unit that did not previously use one, as having both a valve in the return line and one on the channel plate will cause a lube restriction and failure.
Another difference between some early & late channel plates is an additional machined area for the new design 4th clutch that has an additional external tab on the steel plate. This was a running change made mid-year 2002. (BLUE ARROWS)
Part Number Chart
| Part Number | Channel Plate Casting Number | Years | Style | Blow-off Balls |
|---|---|---|---|---|
| GM171 (Warranty Only) | 24211900 | '97-'02 | GM | TCC Only* |
| GM172 (Warranty Only) | 24224086 or 24229721 | Mid-'02-Later | GM | TCC & Converter Drain-back |
| GM173 (Warranty Only) | 24224896 | Mid-'02-Later | GM | TCC Only |
| GM174 (Warranty Only) | 24213496 | '99-'02 | Volvo | TCC & Converter Drain-back |
| GM175 (Warranty Only) | 24224897 or 24229720 | '03-Later | Volvo & GM Tap Shift** | TCC & Converter Drain-back |
*NOTE: Some 24211900 channel plates have both TCC blow-off ball & cooler drain-back blow-off ball. The TAP Shift & Volvo channel plates have a Lo blow-off valve near the manual valve (see red box above) instead of a drain-back blow-off ball.
**NOTE: Looks like a Volvo on the valve body side and uses a late-Volvo-style valve body with 3-piece pump.
Related Parts
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