The Ford Bronco (produced in the Wayne, Michigan, Ford truck plant) was introduced with the ’66 model and lived a long 31-year production life. It was designed to be an all-purpose vehicle, drawing many of its design cues from the F-100 and F-150 pickup trucks of the same era. The last year of production for the United States was marked by the ’96 model and was then replaced by the four-door Ford Expedition.
The Bronco evolved into a fullsize SUV with capable 4WD axle systems, V-8 engines, and roomy interiors. As with the popular Ford pickups, the aftermarket offered plenty of upgrades for the Bronco, and crossover OEM parts were plentiful.
1st Generation (1966-1977)
The earliest ’66-’77 Broncos looked unlike the F-series pickups of the day and the original body was a bit smaller in size. The relatively short 92-inch wheelbase SUV sat on a ladder-frame but not the same frame as the pickups.
The early Broncos were offered in three body styles. The Wagon was the most common and offered a full-length roof with upper body sides installed on the basic body. The top and upper body sides could be unbolted and removed, as desired. The Pickup (until the ’72 model) came with a short steel roof that was also removable, and weighed 70 pounds. The Roadster model (until ’68) had no roof or doors. Smooth, contoured door openings filled in a portion of the area where full steel doors were used on the other models. Optional doors and a soft-top were available as options. The models offered either bench or bucket front seats, and an optional rear seat.
Up front, Ford offered what it called the Mono-Beam Suspension. Straight axles were used with the front axle connected to the chassis via forged steel radius arms and a lateral track bar. Ford boasted about the “wide” 57-inch track width of the first-generation Bronco. Coil springs were used up front, while conventional leaf springs were used in the rear. Standard and heavy-duty suspension systems were offered from the factory.
Steering was via a worm and roller-style steering box mounted to the driver-side framerail and a drag link running toward the passenger-side knuckle. A Saginaw power steering option was added starting with the ’73 Bronco.
A number of carbureted engines were offered in the first-generation Broncos. These included the 170ci I-6, 200ci I-6, 289ci Windsor V-8, and 302ci Windsor V-8 (exclusive for ’75-’77 trucks). The three-speed Ford 303 manual transmission was a column-shifted gear changer and the C4 three-speed automatic was offered behind the 302ci V-8 starting in the ’73s. The iron-case, gear-drive transfer case was a Dana 20 in either T-shift pattern (2.46:1 low range) for ’66-’72, or J-shift pattern (2.34:1 low range) for ’73-’77. A PTO output at the transfer case was also available during the early years of the Bronco.
Front axles with freerunning hubs were either the Dana 30 (up until about the ‘71s) or later switching to the heavier Dana 44. The Ford 9-inch axle was used in the rear, and gearing for the first-generation Bronco ranged from 3.50 to 4.57 over the 12-year span. A limited slip or Traction-Lok was optional in the rear axle. Early brakes were drum-drum systems, with front discs and power assist (optional) added for the ’76s. Options on the early models included items such as snowplows, front overload air springs, and winches.
2nd Generation (1978-1979)
Ford did a major body redesign for the ’78 model year. The new Bronco was larger and based on the F-series truck. The wheelbase grew to 104 inches, and overall width grew about 10 inches as well. The larger Bronco could now seat six occupants, and we chose the ’78 Bronco as Four Wheeler of the Year.
The new Bronco used much from the pickup truck line, including body panels, chassis construction, and drivetrain components. The top was still a removable item. The rear glass retracted electrically into the tailgate on these models, though many of these would prove to be problematic.
Engine choice for the second-generation Bronco was limited to the 351M or 400M V-8, both with two-barrel carburetors. Transmission choices included the BorgWarner T-18 four-speed manual (6.32:1 First gear), New Process NP435 four-speed manual (6.69:1 First gear), or the C6 three-speed automatic.
Transfer case choice was either the full-time 4WD NP203 iron-case chain-drive transfer case (1.96:1 low range) or the part-time 4WD NP205 iron-case gear-driven transfer case (1.96:1 low range).
The front axle remained a Dana 44 straight axle and the rear remained the Ford 9-inch. Axle gearing was 3.50:1 or 3.55:1. Power disc-drum brakes were standard on these models and power steering became standard beginning with the ’79s.
3rd Generation (1980-1986)
Another redesign occurred just two years later and the ’80 Bronco was introduced. Ford made a drastic change to the front axle and suspension system with the use of the Dana 44 Twin-Traction Beam (TTB), a style of independent front suspension. Coil springs remained as the spring of choice up front and leaf packs remained in the rear.
Ford offered a reliable 300ci I-6 along with several larger engine options. There were the 302ci V-8, 351M V-8, and the more powerful 351ci Windsor V-8 scattered amongst the third generation years. Also, multi-point fuel injection was introduced on the 302ci V-8 in the ’85 models and on the remaining engines a few years later.
Transmissions included the T-18, the Tremec RTS overdrive four-speed (starting in ’81 models), the C6, and the Ford AOD four-speed automatic overdrive (starting in 1985). The transfer case was changed to the NP208 aluminum-case, chain-drive (2.61:1 low range) unit.
The Ford 9-inch rear axle was dropped and the 8.8-inch axle introduced in its place in the ’83s. Axle ratios ran from 3.00:1 to 4.11:1, and new automatic hubs allowed shifting from two-wheel to four-wheel drive while the vehicle was moving.
4th Generation (1987-1991)
The ’87 Broncos made another cosmetic change with a bit more aerodynamic look to the front end. The TTB front suspension and leaf spring rear remained.
An option with the 300ci I-6 or 302ci V-8 starting in 1988 was the Mazda-built M5OD-R2 five-speed manual overdrive transmission. The C6 and AOD autos continued to be used until the ’90 models, then all automatic Broncos came equipped with the E4OD transmission. The transfer case in this generation was the magnesium-case, chain-drive BorgWarner 1356 (2.69:1 low range) and axle ratios were typically 3.55:1 or 4.10:1.
5th Generation (1992-1996)
For the ’92 model, the Bronco was updated, along with the F-series pickups. The top was still physically a removable item, but Ford made the process more difficult. They installed Torx security bolts to secure the top to the body and discouraged owners from removing them.
The 300 I-6 was discontinued after the ’93’s production ended. The 302ci V-8 was swapped to a Mass Air Flow (MAF) fuel-injection system for the ’94 model and the 351ci V-8 did the same a year later. OBD-II engine control and monitoring was introduced in 1996. Four-wheel antilock brakes became standard with the ’93s.
The final model year of the Bronco was the ’96, and the short-wheelbase 4WD would give way to the Expedition as the prime SUV in the Ford lineup. Rumors abound concerning the return of a Bronco model in the Ford lineup, but only time will tell if it truly happens.