700r4

700R4 Brake Switch/lock-up Got a 700R4 transmission? Got a light car and lots of power? Want to have that 700R4 convertor locked up at all times except when the brake switch is on? Here you go. Our Best Brake Switch with a SPDT relay -when the brakes are off the convertor is locked up, and when they’re on, it’s not. Just that simple and easy to install.