GrudgeBox Builder's Kit Configuration:2018-Up M8 Softail, Polished Door, N1 Shift Pattern We did not stop at

We did not stop at just fixing the gear ratios

Less shift clunk - Each design improvement combines in a precise mechanical choreography that is inherently silent

The economy is the backbone of a nation

The F6R kit adds a reverse gear to any existing 2006-later factory big twin 6 speed

Bolts & Washers

GrudgeBox Builder's Kit Configuration:2018-Up M8 Softail, Polished Door, N1 Shift Pattern We did not stop atThe GrudgeBox is a tough overdrive 6 speed to replace your stock 6 speed! The GrudgeBox was engineered with a focus on excessive torque capacity and crisp shifting. All gears are straight cut in a way that ensures maximum power transfer to the rear wheel. This gearset was designed and geared for the everyday highway riders, speed freaks, and even racers! Features Built to take high horsepower abuse found in late model H D performance applications