Chrysler 727 and 904 Pro Brake Part Installation

Your Chrysler 727 / 904 Pro Brake valvebody is designed to have a reverse lockout safety feature. To engage reverse, the shifter must be placed in reverse and the Trans brake switch must be depressed simultaneously. Install a good bolt-in sprag! If necessary, refer to a transmission manual for detailed instructions on disassembly and reassembly. The transmission should be completely disassembled, and thoroughly cleaned.

After disassembly, drill hole in case with 11/32” drill bit and then tap with 1/8” NPT TAP, then install electrical connector.
Use a 1971 and up, 4 clutch, Front Clutch
Pack Drum with wide bushing (recommended). It must match the front pump support bushing area.
Drill a 1/16” bleed inside the piston next to the 90-degree sealing edge between spring towers. Use a 15-spring piston; install all 15 of the 1.4 late model springs.
Set the high clutch pack clearance to .060”-.080”.
Set the Fwd. clutch pack to .030”-.040”.
Take the front pump support and cut or mill opening at hole, between sealing rings that feed the drum, down to the intersecting hole. Be careful not to damage the ring landing supports.

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