American Powertrain now offers a Tremec 4×2 TR-4050 five-speed Pro-Fit HD manual transmission kit designed for 1988-98 Chevy/GMC OBS light- and medium-duty trucks.
The Chevy/GMC OBS 4×2 kit includes a short throw White Lightning Shifter designed for the TR-4050, a crossmember adapter bracket that works with the original factory crossmember, bell housing, hydraulic bearing, pilot bearing, reverse light harness, shifter knob, and all hardware for installation. The kit can be used with a stock pedal; however, a complete hydraulic pedal conversion system for OBS is available.
The new OBS 4×2 kit from American Powertrain features the new Tremec TR-4050 4X2 transmission which has a torque rating of 600 lb.-ft., and gear ratios of 6.16, 3.11, 1.71, 1, .76 od. Rev 6.03. Advantages highlighted by the company include a 30% increase in fuel economy; lower RPM cruising for greatly reduced driver fatigue; reduced engine wear for longer engine life; and cooler engine operating temperature.
Additional features shared by the company include:
- High-contact constant-mesh helical gears for maximum strength;
- Diecast aluminum alloy housing saves weight while offering considerable rigidity;
- Tapered bearings on input, main and counter shafts provide excellent internal stability;
- Needle bearings under gears reduce friction and noise output;
- Revised fifth gear retainer eliminates problems associated with NV 4500 overdrive output shaft nut;
- All forward gears and reverse synchronized;
- Advanced synchronizer technology promotes smoother shifting and reduced shift effort; and
- Countershaft mounted fifth gear synchronizer reduces noise in overdrive.