Sonnax forward clutch hub front washer 34298-078 replaces the OE .063" thick washer in GM TH400, TH425, 4L80-E and 4L85-E transmissions between the forward clutch hub and the forward drum. It is .015" thicker than OE and is the optimal way to tighten front unit endplay in most common builds.

Shimming at this location does not alter the endplay path through the unit. This washer is an alternative to the Sonnax washers 34301-078 and 34301-094.

• Forward hub washers are .015" thicker than OE
• Installation between the forward drum and forward clutch hub reduces front unit endplay