Early Bronco Dana 20 Transfer Case

The 1966–1977 early Ford Bronco was equipped with the Dana 20 transfer case as standard equipment. The Dana 20 is a part-time 4WD unit with high and low range operation, suited for medium off-road use. It was available in both a floor-shift T & J-shift configuration. The T-Shift application ran from 1966-1972, and the J-Style went from 1973-1977.

Rebuilding an early Bronco Dana 20 transfer case involves disassembly, inspection of the mainshaft, gears, shift forks, and bearings, followed by replacing worn components with a rebuild kit. Tom's Offroad carries Dana 20 rebuild kits with all gaskets, seals, and snap rings. This is a moderate DIY job for someone comfortable with manual drivetrain work.

The Dana 20 transfer case in early Broncos uses GL-5 80W-90 gear oil. Always check the fill level when buying a used Bronco, as neglected fluid is a leading cause of Dana 20 wear. Drain and refill the fluid as part of any restoration or major mechanical service.

The 1969 Ford Bronco was equipped with the Dana 20 transfer case, the same unit used throughout the 1966–1977 production run. The 1969 model used the t-shift floor-mounted shifter design. Parts for the Dana 20 are widely available, and rebuilding or upgrading the case is well-documented in the early Bronco community.

Yes, many early Bronco builders swap the Dana 20 for a stronger unit like the Atlas or New Process 205, which offers a better low-range ratio and stronger construction for serious off-road use. These swaps require custom driveshaft modifications and shifter relocation but are popular in builds running larger tires and engines.