A common problem in GM 200-4R and 4L60 transmissions is burned bands and/or 3-4 clutches. This failure can be reduced by eliminating throttle boost oil leakage. Sonnax drop-in TV boost valve kits 77917-02K (.423" dia.), 77917-03K (.471" dia.) and 77917-04K (.500" dia.) eliminate these problems in a variety of applications. For maximum pressure and shift feel for high performance applications, use Sonnax TV boost valve kit 77917-04K.
| Sonnax Part No. | Sleeve Dia. | Performance Applications | 
|---|---|---|
| 77917-02K | .423" dia. | Minimum line pressure for V6 applications and smaller vehicles | 
| 77917-03K | .471" dia. | Higher line pressure for towing and off-road | 
| 77917-04K | .500" dia. | Maximum line pressure and shift feel for high performance applications | 
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.
 
              