Sonnax Heavy Duty Reverse Clutch Piston Kit - SX28761-01KPG HEAVY DUTY REVERSE CLUTCH Suit GM Powerglide Part Number: SX28761 01K Sonnax heavy duty reverse clutch piston kit 28761 01K for GM Powerglides is configured to utilize four frictions and five steels. It can also be machined to accept additional frictions and steels for transbrake applications. To reduce rotating weight in circle track applications, two frictions (rotating) and seven steels (non rotating) can be used. High strength piston will not