<P> In a move towards fuel efficiency, Ford dropped the M - Series engines (the 5.8 Liter 351M and 6.6 Liter 400 cu in V8s) in 1981, replacing them with the 4.2 Liter 255 C.I. and 5.8 Liter 351 C.I. Windsor V8 engines from the Panther platform . The 255 V8 was simply a 5.0 L, 302 V8 with a smaller bore, built specifically for better fuel economy, but was dropped for the 1982 model year due to being underpowered and having limited demand . For 1982 and 1983, the 3.8 L, 232 C.I. Essex V6 was the base engine but was quickly dropped for the 1984 model year . In 1983, Ford added Diesel power to the F - Series through a partnership with International Harvester (later Navistar). The 6.9 L, 420 C.I. IDI V8 produced similar power output as the gasoline 351 Windsor V8, with the fuel economy of the 4.9 L, 300 I6 . From this point on (1983 - present), the heavier duty f - series trucks (F - 250 and above) were usually equipped with the Diesel engines as standard horsepower. 1985 was the first year of electronic fuel injection on the 5.0 L V8, all other engines following suit in 1988 . There was a new "high output" version of the 5.8 L Windsor beginning in 1984 . </P> <P> A noticeable change was made to the F - Series in 1982 as the Ford "Blue Oval" was added to the center of the grill, also the Ranger and Custom trims were no longer available . The Ranger name had been shifted onto the all - new compact pickup developed as a replacement for the Courier . The new trim levels were a no - badge base model (essentially the new Custom), XL, a very rare XLS, and XLT Lariat . </P> <P> 1983 marked the final year of the F - 100, making the F - 150 the lightest pickup available on the market . F - 100s and F - 150s were virtually identical with the exception of smaller brakes and a 5x4. 5 bolt pattern on the F - 100 axles, as opposed to 5x5. 5 on the F - 150 . F - 100s over a certain GVWR and / or without power brakes did use the F - 150 axles . Also, the 1980--1983 F - 100 was never offered with four - wheel - drive . </P> <P> 1986 marked the final year that the F - 150 was available with a 3 - speed manual gearbox that shifted via a steering column lever (3 - on - the - tree). Incidentally, this was the second - last vehicle in the United States that offered this set up . 1986 was also the last year the Explorer package was available . </P>

When did ford switch from f100 to f150