cars used the Dodge Aspen platform (F-body), but with a different body shell known as the M-body, and their primary purpose was as a luxury version of the Aspen/Volaré. The initial 1977 models comprised coupes and sedans, with a Town & Country station wagon appearing for 1978 (using the nameplate formerly carried by full-sized C-body Chrysler wagons). The sedans and wagons, though considered M-bodies, were nearly identical to F-body Aspens and Volarés except for the hoods, trunk lids, and front and rear header panels. The coupes differed more substantially; where the F-body models utilized a 108.7 inch wheelbase coupe, M-bodies (which included the Dodge Diplomat) used a unique coupe with styling evocative of the 1930s on the same 112.7 inch wheelbase as the sedans and wagons. Engines consisted of the 225-cid Slant Six, the 318 V8, and the 360 V8. Most were equipped with the 3-speed Torqueflite automatic transmission, but a four-speed manual gearbox with an overdrive fourth gear was offered with the two smaller engines until 1981. In 1979, the LeBaron was reskinned for the 1980 model year to gain more crisp sheet metal, gaining a waterfall grille which was an Imperial LeBaron feature that appeared in 1974, new headlight fascias, and more angular taillamps. The rear roofline was also made shorter and steeper. The 2-door coupe received new smooth rear sheetmetal, that replaced the old curved rear panels, and was moved to the 108.7 inch wheelbase. On the inside, enhancements were made to the interior to make it more luxurious. Also that year, a limited edition "Fifth Avenue" package was available on the 4-door sedan with an altered roofline and additional content; only 654 LeBarons were produced with this package, all converted by the American Sunroof Corporation. A police package was offered for 1981, after the demise of the Volaré, which was replaced by a new M-body Plymouth Gran Fury for 1982, keeping Chrysler-Plymouth dealers in the competition for law enforcement contracts. The LeBaron model name was moved to the new front-wheel drive K-platform for the 1982 model year. The former M-body LeBaron sedan became the Chrysler New Yorker and could still be equipped with the Fifth Avenue package. The M-body wagons and coupes were discontinued after 1981. Chrysler's M-body sedan was ultimately renamed New Yorker Fifth Avenue for 1983 and then just Fifth Avenue starting in 1984. M-body Fifth Avenue production continued through 1989 little changed from