GrudgeBox Builder's Kit Configuration:2018-Up M8 Softail, Polished Door, N1 Shift Pattern 4 different mainshafts are available

4 different mainshafts are available for Knucklehead

This is easier and cheaper for high volume manufacturing

Function Formed Cable Type Side Cover Assembly

All DD5 bearing doors have the same outer profile as a stock 5-speed

2005-2010 Big Dog Motorcycles Primary Fluid Capacity Dry: 32 fl-oz

GrudgeBox Builder's Kit Configuration:2018-Up M8 Softail, Polished Door, N1 Shift Pattern 4 different mainshafts are availableThe 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