I did a 727 for a budy about a year ago worked good for a year he called the other day said it had no reverce so I took it aroung the block it had 1,2,3 but no reverce. so I pulled the pan and found parts of the servo piston in the pan so I put a new HD piston in it and put it back together and he took it for a ride he was happy. called today and he told me that he pulled out of his shop to get gas and made it about 100'and the car just stopped and that the tranny just locked up. put the car in reverse and it backed up tried to go forwad and locked up again. car 74 Charger mild hot rod 440 converter is a 3800 stall. transgo shift kit. Thanks Ken

The low reverse servo may be cocked in the bore , keeping the low reverse band on at all times. If this happens, reverse, and first will work ok, but will lock up in 2nd gear.

John that what I was thinking but I put a new superior servo piston P/N KO-29 in it. The bore looked good. out side of beening made of steel witch made it heavey its a nice looking part Thanks ken

Seen the low reverse bands break the one tab off.