I am the only person in the UK to blow one of these GV overdrives up. The overdrive was 18 months old and fitted behind the 4 speed in my Road Runner. I emailed GV and Rick Johnson phoned me up almost immediately. He arranged a warranty repair using Overdrive Repair Services in Sheffield and sent them a new clutch and clutch band overnight to fix mine. I had it back in the car within a week. Customer service is second to none. Heres the switch I made for the pistol grip to operate the overdrive.