While most of the Mustang was carried over in late 1982 for 1983, there were some changes and improvements on the then five-year-old "Fox-platform" model. The front end was restyled with a more rounded nose and a V-shaped grille which resulted in the headlamp openings being revised to follow the grille shape. New wider horizontal taillights with dedicated amber turn signals replaced the vertical sectioned units similarly styled to the Ford Fairmont. Ford added aconvertibleto the Mustang line for 1983 in response to the 1982 Chrysler convertibles, this after a nine-year absence. The majority of the convertibles were equipped with the new 3.8L V6 in GLX form, though 993 GT models were also produced. The Mustang GT received a four-barrel carburetor and a new intake manifold, bringing power to 175hp (130kW). The turbocharged 2.3L four-cylinder also returned, now fuel-injected, and producing 145hp (108kW). Turbo GT sales were hurt a higher base price than the 5.0, the lower performance, and the lack of available air conditioning with that powertrain. The 3.8LEssexV6 replaced the 3.3LI6, as the 3.3L engine had little demand and was dropped after 1982.
For 1984, the GL and GLX were dropped, leaving L, LX, GT, Turbo GT, and a new addition, theSVO. Ford also recognized the 20th Anniversary of the Mustang with the G.T.350, which consisted of a limited run of 5,260 hatchback and convertible models all trimmed in Oxford White exteriors and Canyon Red interiors. They featured red G.T.350 rocker stripes and tri-bar Pony emblems on the front fenders. They could be equipped with either the 2.3 Turbo or 302cuin (4.9L) V8. Two 302 V8s were available, the four-barrel, or a new 165hp (123kW) electronic-fuel-injected engine. A new "Quadra Shock" rear suspension, which replaced the slapper bars with horizontally mounted axle shocks, became available after a few months of production. After 1984, the TRX option was retired for the Mustang.