Bronco History, 1966-1977 Early Bronco. 
1978-1996 Big Bronco and 1984-1990 Bronco II 

The Ford Bronco was a sport-utility vehicle produced from 1966 through 1996, with five distinct generations.

It was initially introduced as a competitor for the Jeep CJ-5 and International Harvester Scout. A major redesign based on the Ford F-Series truck in 1978 brought a larger Bronco to compete with the Chevrolet K5 Blazer, Jeep Cherokee, and Dodge Ramcharger. Thus, Broncos can generally be divided into three categories: Early Broncos (1966-1977, full-size Broncos (1978-1979) and full size Broncos (1980-1996). However, no matter which year it was built, four wheel drive and low range were standard on every Bronco built through its thirty year run. The only two wheel drive Broncos were due to modification for street use as after market by their owners. This is especially interesting to note on the 1978 through 1996 Broncos when they were designed on the F-Series pickup truck frame, many of which were two wheel drive with no low range.

The full-size Broncos and the successor Expedition were produced at Ford's Michigan Truck Plant in Wayne, Michigan.

History of the Early Ford Bronco (1966-1977)


The Ford Bronco was introduced to the public in August of 1965. The first Broncos were very Spartan without options such as power steering and an automatic transmission. The first models were available only with a 105 hp 170 ci six cylinder derived from Ford's Falcon lineup. The only available transmission was Ford's 3.03 three-speed manual with a column-mounted shifter. Transmission ratios behind the six cylinder were 3.41:1 first, 1.86:1 second, and 1:1 third. When the 289 V8 option was introduced in March 1966, the three speed manual behind it had ratios of: 2.99:1 first, 1.46 second, and 1:1 third. The transfer case was a Bronco specific Dana 20 with a low range ratio of 2.46:1. Unique to the earliest models was a tall shifter with a shift pattern matching that of the T-handle shifter, but with a J- handle style ball mounted on top. Most '66s also had rear shock absorbers that angled forward in front of the axle with stud mounts at the top instead of the later rear-canted eye mount shocks. The Bronco, with a 92-inch wheel base was offered in wagon, half cab, and roadster configurations. The roadster option was not very popular and was discontinued after 1968. Standard brakes were 11 x 2" front drums and 10 x 2.5" drums on the rear on the small bearing (2780 lb.) axle and 11 x 1.75" drums on the large bearing (3300 lb.) axle. All Broncos employed a Ford 9" rear axle and until 1971, a Dana 30 front axle rated at 2,500 lb. Axle ratios were 3.50:1, 4.11:1 and 4.57:1(6 cyl. only). The standard gas tank held 12.5 gallon with an optional 8.5 gallon second tank available. Later these capacities were increased to 14.5 and 11.5. Options for '66 (including dealer-installed accessories) included: Warn freewheeling hubs, snow plow kits, winches, tachometers, air lift front auxiliary springs, trailer hitches, tow hooks, etc. Most of the options and many others were included through the Bronco's twelve-year run. Production for the 1966 year totaled 23,776 units.


The Sport Package was introduced in 1967. This package included bright finished horn ring, windshield drip, head and tail lamp bezels, side window frames, instrument panel trim and tailgate handle, cigar lighter, chrome-plated grille, bumpers and front guards, red die cast F-O-R-D letters applied to the grille, and 15" wheel covers. A bright trimmed hardboard headlining and vinyl floor mat were also added to the Sport Wagon. A dual master cylinder with a split hydraulic system and self-adjusting brakes was also new. Back-up lights were now standard and an 11.5-gallon auxiliary fuel tank option was available. 14,230 Broncos were built in 1967.


Bumpers with curved ends and side marker reflectors immediately distinguished the 1968 models from their predecessors. Locking front hubs, new inside door handles and "soft" window crank knobs were other new options. This was also the last year for the 289 V8 and the roadster option. 1968 production was 16,629 trucks.


1969 was a big year for the Bronco with production jumping to 20,956 units. The 302 V8 replaced the 289 V8. Two speed electric windshield wipers replaced the vacuum units several months into the production run. Amber lensed parking lights replaced the previously used white lens. The Sport models now had aluminum door panel trim, pleated parchment interior, and a rear floor mat when the rear seat was ordered. Some sources say the removable top feature was discontinued, although we enthusiasts know better! The steering stabilizer became a standard feature along with improvements in NVH.

Repositioned side marker lights and reflectors were the most obvious change to the 1970 Broncos. The Sport Bronco became a model rather than an option package. 1970 also saw the first application of evaporative emissions recovery systems with gas tanks on models so equipped losing capacity to 12.7 gallons and 10.3 gallons in the main and auxiliary tanks respectively. 18,450 Broncos were built in 1970.

The stout Dana 44 became the standard Bronco front axle early in the 1971 production year, replacing the weaker Dana 30. New options included a remote control left hand outside mirror, a new headliner for the pickup, and a heavy-duty radiator. The special edition Baja Bronco by Bill Stroppe and Associates was also introduced this year. Stroppe took a Bronco wagon and added a roll bar, dual shocks front and rear, Gates Commando tires, fender flares, larger tires, rubberized steering wheel, bumper braces, power steering, automatic transmission, special nameplate, and red, white, blue, and black special order paint. A total of approximately 650 Baja Broncos were produced between 1971-1975. 19,784 Broncos rolled off the assembly line in 1971.

1972 was the last full year for the T-handle transfer case shifter and the '302' emblem disappeared from the front fenders of V8 Broncos. This was also the last year for the beloved half cab. The Ranger trim package was introduced at mid-year and consisted of new stripes, argent grille, color-keyed pile front and rear carpet, deluxe wheel covers, wood grained door trim panels, 'Ranger' tire cover, cloth-inserted bucket seats and a fiberboard headliner. Gas tank size continued to shrink with the auxiliary tank now holding 7.5 gallons. 1972 Bronco production totaled 21,115.

When the Bronco was introduced in the mid-sixties, its main competition was the Scout 800 and the Jeep CJ-5, both Spartan vehicles to say the least. By the early seventies, with the introduction of the Chevrolet Blazer and the Scout II, it became painfully obvious that the Bronco was beginning to fall behind the competition. In 1973, Ford finally answered the calls for modernization by introducing the C-4 automatic transmission option and optional power steering. The C-4 had ratios of 2.46:1 low, 1.46 second, and 1:1 third. The power steering box was a Saginaw unit with 5.3 turns lock-to-lock. The base engine was bumped from 170 to 200 cubic inches. The J-handle transfer case shifter was introduced shortly after the model year began and the low range transfer case ratio became 2.34:1. These changes helped push early Bronco sales to their second best year ever: 21,894.

By 1974, the 200 c.i.d. six cylinder and 4.11 axles were no longer available in California. A new emissions package was also introduced for California Broncos. Some subtle changes were made mid-year to the J-handle shifter mechanism in response to complaints of tough shifting. The transmission selector was lighted starting in '74. 25,824 Broncos rolled off the assembly line in 1974.

Unleaded fuel engines and catalytic converters were the new items added to the Bronco in 1975 in the face of increasingly strict emissions requirements. Some sources also say that the cam timing on '75 engines was retarded to help with emissions as well. Sport and Ranger models received the F-Series steering wheel for the year. GVWs and ride heights were revised. Among the new options was an 800-watt engine block heater for folks in cold climates. Bronco production shrunk to its lowest ever in 1975 with just 13,125 trucks produced.

The bicentennial year brought several key improvements to Ford's sport utility, most notably the addition of long overdue power assisted front disc brakes. The rear brakes were upgraded to 11 x 2.25" drums. The steering box ratio was shortened to 3.8 turns lock-to-lock. The dreaded Y steering linkage was also introduced in 1976 along with a front anti-sway bar. A Special Decor Group comprised of a flat black-finished grille, tape stripe, bright windshield molding, and side window frames and wheel covers was introduced mid-year. 15,256 Broncos rolled off the line in 1976.

Everyone knew the early Bronco's days were numbered in the face of stiff competition from the Blazer and Chrysler Corporation's Ramcharger and Trail Duster trucks. The 1977 Bronco in many ways represented the best of the breed. There were very few changes from the previous year; the most important one for enthusiasts being the introduction of the heavy-duty 9" rear end housing. The most obvious exterior change was the introduction of gas tank doors replacing the previous exterior mounted caps, in line with the introduction of doors on the F-Series and Econoline vans. The rear marker lights were mounted vertically to give clearance for the doors. Some previously standard items, such as a passenger's side seat and padded instrument panel, were made optional this year. Unique to the '77s is a 14.4 plastic gas tank and an 8-gallon auxiliary tank. In its final year of production, 14,546 Broncos rolled off the assembly line before the large Bronco took over in 1978.

History of the Big Bronco (Fullsize 1978-1996)


The Bronco was offered with a 351M or 400 V-8 engine. Both engines had a 2 bbl carb, a T-18 granny first gear 4 spd manual was standard while 3 spd automatic transmission was optional. The transfer case had a 2 Speed w/1.92 low range ratio. Rear axle was the Ford 9" while front was the Dana 44. Front disc brakes were now standard. Round headlights were standard, while square headlights came with the XLT option package.


Square headlights and emissions control equipment, specifically an air pump, vapor canister and a catalytic converter became standard.


Ford converted the Bronco with the Twin Traction Beam front suspension. This front axle still incorporated the Dana 44 carrier. Ford 9 " was still out back. Transfer case was now the NP 208 w/2.61 low range. Standard motor was the 300 CI inline 6 (w/ manual trans only). Optional motors were the 302 and 351 cid V-8's. 3.00 axle ratio was introduced, 3.5 was optional. Auto locking hubs were now optional also. Bronco dimensions for 1980 were reduced by 2.7 inches in length and 1.1 inches in width. Body was heavily restyled with cleaner lines and new grille.


Changes included a 4 spd overdrive manual trans with a .71 4th gear The 4 spd with granny first was still available. Engine options remained. Auto-locking hubs were made standard equip. A snow plow package was offered for the first time.


Ford used up their remaining stock of 351M engines before switching over to the 351W in mid-model year 1982. All Ford products, including Bronco, returned to the use of the Ford "Blue Oval". Letters F-O-R-D were removed from the hood and the blue oval was placed in the center of the grille and on the left side of the tailgate.


The I-6 was made avail with the 3 spd auto and the rear seat was now standard. 9" rear dropped in favor of new integral carrier 8.8" rear. Along with that change the stock gear ratio in the rear went from 3.50 to 3.55.


The 351 CID V-8, HO motor was offered. This 4bbl motor put out 210 HP at 4000 RPM vs the old 351 CID V-8 which was 156 HP @ 4000 RPM It was basically a 351W with a "Mustang 5.0 HO" treatment: higher compression and a Holley 4 barrel carb. 4.10/4.11 gear ratios were also available as an option, but not with limited slip.


had some engine changes. the I-6 now had a serpentine belt. The big change was the 302, multi-port EFI. HP for the 302 was now 190 and torque was up to 285. This motor was avail in California only with a manual trans. The 351 and 351 HO motors were optional. The Eddie Bauer trim package debuts, brought to the full-sized Bronco due to fabulous success with the Bronco II. Also, midside body moulding changed from chrome to black plastic.


1986 saw the 351 CID standard engine deleted, but the 351 HO was still optional. A new overdrive 4 speed automatic (AOD) was offered with a .667, 4th gear when combined with the MPI 302.


1987 featured another major body restyling for the Bronco. The new aero look was in and the Bronco followed suit. The transfer case was replaced by a Borg-Warner 1356 with a 2.69 low range. 4.10 gearing was optional. Touch drive was first offered this year. The 351 HO V-8 was still optional and the 300 CID I-6 received Multiport fuel injection (MPI). Rear antilock brakes were made standard.


Two 5 spd manuals, M5OD and M5OD-HD(?) were available. The overdrive was .8 and the HD tranny had a 5.72 first gear. The 351 CID V-8 was treated to MPI. HP increased from 190@3800-210@3800. Torque increased form 295@2600-315@2800. The entire engine line was now fuel injected and also serpentine belt equipped. Transfer case skid plate was now standard.


Tip/slide front seats were made standard to ease rear passenger ingress.


1990 brought the electronic AOD and it was now the standard auto. 300 CID and 351 CID HO engines now featured EEC-IV engine diagnostic connectors.


1991 was the 25th anniversary of the Bronco and no long-term changes were made. However, Ford did make a Silver Anniversary Edition of the Bronco available to commemorate the occasion. This limited edition Bronco was offered only in Currant Red with gray leather interior. This was the first factory offering of leather seating on the Bronco and was only available on the Silver Anniversary Edition. The Currant Red paint was also exclusive to this edition. The E4OD became the stock automatic transmission.


1992 realized the last major body restyling in the Bronco's life-span. This change offered much more swept front sheetmetal that curved in at the fenders. Power window/lock controls moved up the door panel towards the top to make them more accessible. Power mirrors are now offered for the first time. Rear passengers are restrained via integral shoulder/seat belts. Colored stripe in the tailgate bezel is changed from red to black. Leather seating is now an option on XLT and Eddie Bauer trim levels. Ford also offered the NITE option package, for only this year. The package was all black, including the top. Special graphics were applied.


1993 brought the end of the 300 CID I-6. 4-wheel antilock brakes were now standard. Transfer case was now a New Process model 200 with low range of 2.69.


1994 brought us a drivers side airbag, side door beams and CFC free A/C. Fake rivets disappear from the optional aluminum wheels. Center hub bezel on steel and aluminum wheels changed from red to black. California V8's went from Speed density to MAF.


Ford reprogrammed the E4OD automatic transmission for smoother shifts. The 351 CID V-8 went to sequential MPI with mass air in california. Lower body side trim color for Eddie Bauer package is changed from the traditional tan to bronze.


1996 last year for the Bronco, debuted OBD-II electronics. Side mirrors with integral signal lights were offered for the first time. 302 CID and 351 CID HO MPI motors were still offered. The axles were still the 8.8 inch out back offered in 1983 and Dana 44 TTB front that started in 1980. All V8's got MAF as well.

Riddle,Trent "BRONCO 30th Anniversary." Ford Truckin Magazine Winter 1997 Edition

History of the Bronco II (Bronco 2 1984-1990)

The Ford Bronco II was a compact SUV sold between 1984 and 1990 as a smaller complement to the full-size Ford Bronco, as well as to compete with the Chevrolet S-10 Blazer and Jeep Cherokee. It was very mechanically similar to the Ford Ranger pickup, but had a 94 in (2,388 mm) wheelbase (similar to a Volkswagen Beetle) and was enclosed in the rear.

The 1984 and 1985 models were equipped with a 2.8 L V6, which was similar to Ford's 2.8 L available in Europe. The 1986 model year introduced a 2.9 L EFI V6. This engine was doomed from the beginning with design flaws, often suffering premature cylinder head failure and loss of valve train lubrication if not rigorously maintained. Although these flaws had been fixed by the 1989 model year, the Bronco II was steadily becoming unattractive to potential buyers due to safety concerns.

The Ford Bronco II was known to tip over in some circumstances - as with most SUVs - due to the high center of gravity, and led to a NTSB investigation along with criticism by independent automotive safety groups. The Bronco II underwent a major redesign, and was re-released as the wider and longer Ford Explorer in 1991.

Despite its reputation as an unreliable, unsafe vehicle, the Bronco II is still actively sought-after by those in the market for a cheap, solid, compact SUV. Its similarities to the Ford Ranger make it an easy vehicle to work on as well. Many engine swaps that are popular with the Ranger, such as a Ford Windsor engine, are also easily possible with a Bronco II.

The 1989 and 1990 model years featured a completely redesigned front fascia, which made the Bronco II look much more like the F-Series trucks and the full-sized Bronco. These are known as "second generation" Bronco IIs, even though it is not a true second generation. The 1990 model year and a few late 1989 model year Bronco IIs featured the Dana 35 front axle which replaced the weaker, and more prone to breaking, Dana 28.
First generation
Production     1966–1977
Body style(s)     Compact SUV
Engine(s)     170 in³ Straight-6 (1966-1972)
200 in³ Straight-6 (1973-1974)
289 in³ Windsor V8 (1966-1968)
302 in³ Windsor V8 (1969-1977)
Wheelbase     92.0 in (2337 mm)
The original Bronco was an ORV (Off-Road Vehicle), intended to compete primarily with Jeep CJ models and the
Second generation
Production     1978–1979
Body style(s)     Full-size SUV
Engine(s)     351 in³ 351M V8
400 in³ Modified V8
Third generation
Production     1980–1986
Body style(s)     Full-size SUV
Engine(s)     300 in³ Straight-6
302 in³ 302 V8
351 in³ 351M V8 (1980-1982)
351 in³ Windsor V8
Transmission(s)     4-speed Borg-Warner T-18 manual
4-speed New Process NP435 manual
4-speed Tremec RTS OverDrive
3-speed C6 automatic
4-speed AOD
Wheelbase     104.0 in (2641 mm)
Length     180.3 in (4579 mm)
Width     79.3 in (2014 mm)
Height     75.5 in (1917 mm)
Forth generation
Production     1987–1991
Body style(s)     Full-size SUV
Engine(s)     300 in³ Straight-6
302 in³ 302 V8
351 in³ Windsor V8
Transmission(s)     5-speed M5OD-R2 manual
3-speed C6 automatic
4-speed AOD automatic
4-speed E4OD automatic
Wheelbase     104.7 in (2659 mm)
Length     180.5 in (4585 mm)
Width     79.1 in (2009 mm)
Height     1987-89: 74.0 in (1880 mm).
1990-91: 74.5 in (1892 mm)
Fuel capacity     33 US gallons (124.9 L/27.5 imp gal)
Fifth generation
Production     1987–1991
Body style(s)     Full-size SUV
Engine(s)     300 in³ Straight-6
302 in³ 302 V8
351 in³ Windsor V8
Transmission(s)     5-speed M5OD-R2 manual
3-speed C6 automatic
4-speed AOD automatic
4-speed E4OD automatic
Wheelbase     104.7 in (2659 mm)
Length     180.5 in (4585 mm)
Width     79.1 in (2009 mm)
Height     1987-89: 74.0 in (1880 mm).
1990-91: 74.5 in (1892 mm)
Fuel capacity     33 US gallons (124.9 L/27.5 imp gal)
Ford Bronco II
Production     1984-1990
Assembly     Louisville, Kentucky
Successor     Ford Explorer
Class     Compact SUV
Layout     Front engine, rear-wheel drive / four-wheel drive
Engine(s)     2.8 L Cologne V6
2.9 L Cologne V6
Transmission(s)     Manual
4-speed Mazda TK4
5-speed Mazda TK5
5-speed Mazda M5OD-R1
5-speed Mitsubishi FM145
5-speed Mitsubishi FM146
3-speed C5
4-speed A4LD
Wheelbase     94.0 in (2388 mm).
Width     68.0 in (1727 mm)
Fuel capacity     23 US gallons (87.1 L/19.2 imp gal)
Related     Ford Ranger
First generation Bronco II
1986 Ford Bronco II XL
Production     1984–1988
Length     158.3 in (4021 mm)
Height     68.2 in (1732 mm)
Second generation Bronco II
Second generation Ford Bronco II
Production     1989–1990
Length     161.9 in (4112 mm).
Height     69.9 in (1775 mm).
Bronco II Full Size
Second generation to fifth generation. Early Bronco
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