Patent ID: 8250967

Claim:
An automatic transmission servo for hydraulically operating a brake band of an automatic transmission, comprising: a housing having a bore engaging portion for engaging an existing servo bore in a case of the automatic transmission and an external portion for positioning externally of the servo bore, the external portion of the housing including an interior bore; a piston disposed in the interior bore of the external portion of the housing for reciprocating movement, the piston being externally remote from the servo bore and having an outer diameter greater than an outer diameter of the servo bore; an actuator rod for engaging and operating the brake band of the automatic transmission, the actuator rod attached to the piston to reciprocate with the piston; and hydraulic circuitry for connecting to existing hydraulic circuits of the automatic transmission for supplying pressurized fluid from the hydraulic circuits of the automatic transmission to reciprocally move the piston and the actuator rod; a cylindrical sleeve removably positioned between the interior bore of the external portion of the housing and the piston for reciprocally supporting the piston, such that the automatic transmission servo can be provided with alternative piston bore sizes by exchanging the cylindrical sleeve and piston in matched sets.