C4 Automatic These parts are just like the stock 73-77 Bronco parts no longer available from Ford. This kit consists of a new main shaft, tailhousing, bearing retainer, seal and hardware. The installation is easy since the cross-member bolts directly to the new tail section. Your 3-speed drive sleeve might need shortened to use with the new output shaft. No driveshaft modifications are necessary. An aftermarket shifter or C4 Auto shifter from a Mustang, Pinto or 73-77 Bronco will be needed. #3510 C4 to Dana 20 Adapter Kit, $479.00

NP435 & T18 4-speed
This setup will give a Bronco a super low 1st gear approximately double that of the stock 3-speed. The NP435 can be found in 67-83 F100-F350. The T18 can be found in 68-82 F100-F250. The trans you select must have a 28 spline output shaft. The new overall length of the NP435 and the adapter will directly replace the original V8 assembly, so no driveshaft modification is necessary. The T18 and adapter are approximately 1” longer than the original V8 assembly so driveshaft mods are necessary. This kit includes a machined aluminum adapter housing, gaskets and bolts. The gearshift handle will have to be rebent to come out under the dash. Mods to the floorboard will also be necessary.
#3555 NP435 & T18 to Dana 20 Adapter Kit, $442

Ford T/C 4-speed
The Ford Top Cover 4-speed, found in 66 and newer Fords, is the best 4-speed available for all-around driving. The way to spot this trans is by it’s 10 bolt top cover. The small block 4-speed from a 289/302 with a 2.78:1 1st gear is the best choice. This kit comes with a new main shaft splined to accept the stock sleeve in the transfer case, seals, gaskets and a special bushing to be installed in your stock V8 3-speed tail section, which requires minor modification. Crossmember doesn’t need to be relocated and the 3-speed clutch linkage can be kept. Our #2101 4-speed shifter is needed to complete the job.
#3550 4-speed to Dana 20 Adapter Kit, $267.50
#3558 Overdrive to Dana 20 Adapter Kit, $337.75
#3680 2F 5-Speed / Dana 20 Adapter Kit, $385.00

Duffy’s Original 3-Speed Shifter Stock column shifters on Broncos have always been troublesome. The stock rods bend causing the neutral gate to go out of alignment making shifting difficult. Sometimes the release pin on the collar eggs out, letting you take the shifter with you! Our 3-speed floor shifters eliminate those problems and make shifting a joy again! Other shifters run your knuckles into the dash, so we shortened the throw 4” and added a 1” offset to the right for extra leg room. Included is the rubber boot, bezel, walnut knob, decal and white fiberglass tunnel cover with screws. Designed to fit a V8, but the rods may be shortened approx. 2.5” by cutting, overlapping and rewelding to fit the 6cyl. May be used with the stock transfer case shifter or match it with our transfer case shifters sold below. #2201 73-77 3-Speed (for J-pattern Transfer Case), $329.95 #2202 66-72 3-Speed (for T-handle Transfer Case), $329.95

3-Speed Shifter Rebuild Kit
This is for those of you that have had our shifter for years and now it needs a little freshening up. Since we’ve been making this kit for over 30 years (some of our shifters have several hundred thousand miles on them by now) we realize that some of the parts may be worn and need replaced. This kit comes with a new chrome handle, a walnut knob, boot & bezel, shift rods and rod bushings. The shift rods are threaded at both ends for the best possible fit and fine tuning. This kit can also be used to convert a worn out 3 speed Hurst linkage to one like ours. Handle is offset to the right to increase legroom and is shorter so your knuckles don’t hit the dash.
#2300J 3-Speed Shifter Rebuild Kit (J-Pattern), $110.00
#2300T 3-Speed Shifter Rebuild Kit, (T-Pattern), $110.00

Transfer Case Shifter
A perfect match to our 3 or 4-Speed Shifter Kits. Eliminate the T handle jamming in your 66-72 Bronco. Includes chrome offset handle embossed with “Duff’s,” walnut knob, decal, boot and bezel.
#2102 T-Handle Transfer Case Shifter, 66-72 Bronco, $87.50
#2103 Replacement Tunnel Cover, $52.75
#2104 Replacement Boot, $14.50
#2105 Wood Knob -- SPECIFY PATTERN $11.50 each

Twin Stick Shifter for T-Pattern Dana 20 Tired of fighting that stock shifter?  By separating the shift rails and using twin shifters this kit makes for easier trouble-free shifting. Designed to match our floor shifters with chrome handles and walnut knobs. Requires minor modification to the shift rails and floor board for installation. Includes Boot & cover panel.  Works with stock 3 speed. #2122  T-Pattern Twin Stick, $219.00

Twin Stick Shifter for J-Pattern Dana 20 Transfer Case Tired of fighting that stock J-shifter? By separating the shift rails and using twin shifters this kit makes for easier trouble-free shifting. An added bonus is a variety of gear options allowing you to better utilize the Dana 20, controlling the power to the front and rear separately. Requires minor modification to the shift rails and floorboard for installation. Includes chrome shift handles embossed with the Duff name, wood knobs with domed decals to match our 3 and 4-speed floor shifters, boot & cover panel. #2152 J-Pattern Twin Stick, 1973-77 Bronco, $199.00

“J” Pattern Transfer Case Shifter This J pattern shifter is a brand new unit with a revolutionary design. Our design is spring loaded for smooth shifting and includes brass oilite bushings which never need lubed, thus providing long life and trouble free operation for years to come. Easy to install—simply remove the old shifter and replace it with a complete new unit using the original bolt holes. Includes chrome handle, new bolts, walnut knob, decal, boot and bezel to match our other shifters. #2150 J Pattern Shifter 73-77 Bronco, $179.75

Tranny Cooler Low speed four wheeling puts tons of heat into the fluid of the transmission. Heat is the number one reason for automatic transmission problems. Get rid of the heat with this 6-pass high flow Flex-O-Lite cooler with its own built in thermostatically controlled fan (reversible) and shroud. This allows it to be mounted anywhere there is room and still be able to have air flow for efficiency in dissipating heat. Unit is 10 1/2 x 15 x 4 1/4” with barb fittings for easy hook up to your transmission lines. Comes with mounting hardware to hook it up to the radiator or to remote mount it. A must have for Rock Crawling with an Automatic. #3126 Tranny Cooler, $299.00

3231 NW Park Dr., Knoxville, TN 37921 Phone: 1-865-938-6696 7am-3pm M-F West Coast 10am-6pm M-F East Coast Fax: 1-865-938-6746 24 Hours