1987-1991 Ford F-250OBS F-250 (1987-1991)

Ford F-250 1987-1991 year by year

What the "OBS" label means

The 1987 Ford F-250 introduced the eighth-generation F-Series, a major refresh that kept the underlying Bullnose chassis but gave the truck a smoother front end, flush composite headlamps, and a redesigned interior. Because the 1987-1991 and 1992-1996 trucks share the same basic cab, enthusiasts group them under the term "OBS," for Old Body Style, a label coined after the very different 1997 light-duty redesign. The 1987 Ford F-250 was among the first American trucks to use composite (aerodynamic, replaceable-bulb) headlamps and came with standard rear-wheel anti-lock brakes, an early adoption of ABS in the truck market. As before, the three-quarter-ton F-250 shared its cab with the lighter F-Series and was distinguished by its heavier chassis and higher ratings.

The diesel change: 6.9L IDI to 7.3L IDI

The 1987 Ford F-250 carried over the 6.9L IDI (indirect injection) diesel V8 from the Bullnose era, but for 1988 Ford replaced it with the larger 7.3L IDI V8, also built by International Harvester. Both were naturally aspirated indirect-injection diesels valued for durability and low-speed torque rather than peak output. The 7.3L IDI became the diesel of the eighth-generation F-250 and would later gain a factory turbocharger and then evolve into the 7.3L Power Stroke in the following generation. The diesel was the heavy-duty workhorse engine of the F-250, aimed at towing and hauling buyers who wanted diesel economy.

Gas engines and transmissions

The gas engines of the 1987-1991 Ford F-250 were the 300-cubic-inch (4.9L) inline-six as the base engine, the 5.0L (302) and 5.8L (351 Windsor) V8s, and the 7.5L (460) big-block for heavy towing. Electronic fuel injection spread across the V8 lineup by the 1988 model year, replacing the remaining carburetors. Transmissions included ZF five-speed manuals and the heavy-duty C6 three-speed automatic, with the E4OD four-speed automatic becoming available for 1989; the E4OD added an overdrive top gear and became the modern heavy-duty automatic for the diesel and big-block F-250.

The Dana 50 Twin-Traction Beam front suspension

The four-wheel-drive 1987-1991 Ford F-250 used a Dana 50 Twin-Traction Beam (TTB) independent front suspension, which became the sole F-250 four-wheel-drive front axle for 1987. TTB is an independent design in which two beams pivot separately, each carrying one wheel. A common misconception is that the OBS F-250 used a solid front axle; the F-250 of this era used the independent Dana 50 TTB, while the solid front axle belonged to the one-ton F-350. The solid front axle would not appear on the F-250 until the Super Duty platform arrived for 1999.

Body styles and trim

The 1987-1991 Ford F-250 was offered in regular-cab, SuperCab, and four-door Crew Cab forms, with the Camper Special package available for slide-in camper duty. Trim levels spanned the work-grade Custom and XL, the better-equipped XLT Lariat, and other appearance and equipment packages offered during the generation.

Frequently asked questions

What generation is the 1987-1991 Ford F-250?

The 1987-1991 Ford F-250 is the eighth-generation F-Series. It is grouped with the 1992-1997 trucks under the enthusiast label "OBS," for Old Body Style, because both share the same basic cab introduced for 1987. It was restyled into the ninth-generation "Aeronose" F-250 for 1992.

What diesel did the 1987-1991 Ford F-250 use?

The 1987 Ford F-250 used the 6.9L IDI diesel V8, then for 1988 Ford replaced it with the larger 7.3L IDI V8, also built by International Harvester. Both were naturally aspirated indirect-injection diesels; the 7.3L IDI later gained a factory turbocharger and evolved into the 7.3L Power Stroke.

What gas engines did the 1987-1991 Ford F-250 use?

The 1987-1991 Ford F-250 used the 4.9L (300) inline-six as the base engine, the 5.0L (302) and 5.8L (351 Windsor) V8s, and the 7.5L (460) big-block. Electronic fuel injection spread across the V8 lineup by 1988.

Did the 1987-1991 Ford F-250 4x4 have a solid front axle?

No. The 1987-1991 Ford F-250 4x4 used a Dana 50 Twin-Traction Beam independent front suspension. The solid front axle in this era belonged to the one-ton F-350; the solid front axle did not appear on the F-250 until the Super Duty platform arrived for 1999.

What was new on the 1987 Ford F-250?

The 1987 Ford F-250 introduced the eighth-generation refresh with composite headlamps, a redesigned interior, and standard rear-wheel anti-lock brakes. The Dana 50 Twin-Traction Beam also became the sole F-250 4x4 front suspension that year.

Sources

• Ford factory specification sheets for the 1987-1991 F-Series
• Wikipedia, Ford F-Series (eighth generation)
• DieselHub references, 6.9L and 7.3L IDI diesels
• Blue Oval Trucks reference, Dana 50 Twin-Traction Beam front axle
• VIN and data-plate decoding for engine and axle identification