Product Description
Fits 2019-later units only!
Tooling Required: F-154740-TL26, VB-FIX
Pressure loss, a burnt 2-3-4-6-8 (S4) clutch and poor shift quality are common complaints with GM 8L45 and 8L90 transmissions. These symptoms can be caused by a worn S4 clutch control valve and bore that allows valuable clutch apply fluid pressure to leak, reducing the force needed to apply the clutch. The Sonnax oversized S4 clutch control valve kit 154740-26K has an added scarf-cut seal at the signal apply end and a lengthened inboard spool at the clutch apply end that seals a reconditioned bore and restores proper function.
- Hardcoat anodized aluminum valve combats premature wear
- Lengthened valve spool utilizes unworn bore section to seal apply oil
- Annular grooves help center the valve in the bore to reduce future side-load wear
- Scarf-cut seal prevent leaks at the signal apply end for proper clutch control
NOTE: Sonnax "F-Tool" kits designed to service a specific bore require the VB-FIX, a self-aligning valve body reaming fixture.
Contents
- Valve
- Spring
- Seal
Symptoms
- Burnt clutches
- Pressure loss
- Poor shift quality
Cause
Wear of the 2-3-4-6-8 (S4) clutch control valve and bore can allow clutch apply fluid pressure to leak, resulting in pressure loss, a burnt clutch and poor shift quality.
Correction
Recover hydraulic control and renew clutch apply fluid pressure performance by reconditioning the bore and installing the Sonnax oversized S4 clutch control valve kit.
