Authenticity reference

Transmission and axle

numbers matching · documented

Reference Details

Common issue: A four-speed and Positraction were added during restoration. · 1964 Chevrolet Impala Super Sport
Confidence: documented · 1964 Chevrolet Impala Super Sport
Correct value: Transmission type, console, floor opening, tags, axle code, ratio, and dates agree with the engine order · 1964 Chevrolet Impala Super Sport
Where to check: case, tag, linkage, tunnel, console, axle tube, carrier, and paperwork · 1964 Chevrolet Impala Super Sport
Common issue: Manual swap, later transmission, or limited-slip conversion represented as factory installed · 1964 Chrysler 300K
Confidence: documented · 1964 Chrysler 300K
Correct value: Console-shift A-727 TorqueFlite or documented four-speed with matching clutch controls; 3.23 rear and any Sure-Grip evidence must agree · 1964 Chrysler 300K
Where to check: Transmission case and controls, pedals, linkage, axle housing and tag, dates, body plate, and records · 1964 Chrysler 300K
Common issue: Manual swap, later transmission, or limited-slip conversion represented as factory installed · 1965 Chrysler 300L
Confidence: documented · 1965 Chrysler 300L
Correct value: Console-shift A-727 or documented four-speed with matching controls, plus 3.23 rear and supported Sure-Grip equipment · 1965 Chrysler 300L
Where to check: Transmission, pedals, linkage, floor opening, console, axle tag, dates, data plate, and records · 1965 Chrysler 300L
Common issue: A four-speed, TorqueFlite, 3.55 gear, or Sure-Grip added during restoration and represented as born-with equipment. · 1965 Plymouth Satellite
Confidence: documented · 1965 Plymouth Satellite
Correct value: Transmission family and axle ratio/Sure-Grip status agree with the selected engine and factory records. · 1965 Plymouth Satellite
Where to check: Transmission case and tag, axle tag, body plate, and order paperwork. · 1965 Plymouth Satellite
Common issue: A four-speed conversion or changed gearset represented as born-with equipment. · 1968 Mercury Cougar GT-E
Confidence: documented · 1968 Mercury Cougar GT-E
Correct value: 427 cars use C6; 428 cars use the documented C6 or one of three registry-recorded four-speeds, with the axle matching car records. · 1968 Mercury Cougar GT-E
Where to check: Data plate, invoice/build report, transmission case/tag, axle tag, and component dates. · 1968 Mercury Cougar GT-E
Common issue: Replacement gearbox or ratio represented as factory installed · 1972 Chevrolet Corvette
Confidence: documented · 1972 Chevrolet Corvette
Correct value: Type, case, tag or stamp, date, ratio, Positraction hardware, and drivetrain compatibility agree with records · 1972 Chevrolet Corvette
Where to check: Transmission case/tag, differential, chassis, shifter and linkage, tank sticker, and service records · 1972 Chevrolet Corvette
Common issue: Four-speed conversions and axle swaps are straightforward and cannot be authenticated from the shifter or ratio alone. · 1973 Buick Century Gran Sport Stage 1 455
Confidence: documented · 1973 Buick Century Gran Sport Stage 1 455
Correct value: factory four-speed or TH400 evidence should agree with the build record; 3.42 appears in federal certification for both transmission paths · 1973 Buick Century Gran Sport Stage 1 455
Where to check: transmission code, axle code, build sheet, window sticker, and Sloan Museum documentation · 1973 Buick Century Gran Sport Stage 1 455
Common issue: Replacement gearbox or ratio represented as factory installed · 1973 Chevrolet Corvette
Confidence: documented · 1973 Chevrolet Corvette
Correct value: Type, case, tag or stamp, date, ratio, Positraction hardware, and drivetrain compatibility agree with records · 1973 Chevrolet Corvette
Where to check: Transmission case or tag, differential, chassis, shifter and linkage, build sheet, and service records · 1973 Chevrolet Corvette
Common issue: Replacement gearbox or ratio represented as factory installed · 1974 Chevrolet Corvette
Confidence: documented · 1974 Chevrolet Corvette
Correct value: Muncie or Borg-Warner four-speed or M40 automatic type, case, tag or stamp, date, ratio, Positraction hardware, and drivetrain compatibility agree with records · 1974 Chevrolet Corvette
Where to check: Transmission case or tag, differential, chassis, shifter and linkage, build sheet, and service records · 1974 Chevrolet Corvette
Common issue: Replacement gearbox or ratio represented as factory installed · 1975 Chevrolet Corvette
Confidence: documented · 1975 Chevrolet Corvette
Correct value: Warner W-code four-speed or CK L48/CZ L82 M40 automatic identification, case, stamp or tag, date, ratio, axle code, Positraction hardware, and drivetrain compatibility agree with records · 1975 Chevrolet Corvette
Where to check: Transmission case or tag, differential, chassis, shifter and linkage, build sheet, and service records · 1975 Chevrolet Corvette
Common issue: A replacement A727 or Sure Grip axle assumed original without tags and date evidence. · 1975 Dodge Charger SE
Confidence: documented · 1975 Dodge Charger SE
Correct value: TorqueFlite and axle ratio/type that agree with engine, option records, tags, stampings, and dates · 1975 Dodge Charger SE
Where to check: Transmission case and pad, axle tag or stamp, broadcast sheet, window sticker, and service records · 1975 Dodge Charger SE
Common issue: A later C4/C6 or Traction-Lok axle presented as original without code and date agreement. · 1975 Ford Gran Torino Sport
Confidence: documented · 1975 Ford Gran Torino Sport
Correct value: W, X, or U transmission code and engine-appropriate axle code/tag that agree with original records · 1975 Ford Gran Torino Sport
Where to check: Certification label/data plate, transmission tag or casting, axle tag, invoice, window sticker or serial-specific Marti report, and service records · 1975 Ford Gran Torino Sport
Common issue: Replacement gearbox or ratio represented as factory installed · 1976 Chevrolet Corvette
Confidence: documented · 1976 Chevrolet Corvette
Correct value: Warner W-code four-speed, AM or XH L48 THM350, or CZ L82 THM400 identification, case, date, ratio, axle code, Positraction hardware, and drivetrain compatibility agree with records · 1976 Chevrolet Corvette
Where to check: Transmission case or tag, differential, chassis, shifter and linkage, build sheet, and service records · 1976 Chevrolet Corvette
Common issue: Replacement gearbox or ratio represented as factory installed · 1977 Chevrolet Corvette
Confidence: documented · 1977 Chevrolet Corvette
Correct value: Warner W-code four-speed, AM L48 THM350, or CB L82 THM400 identification, case, date, ratio, axle code, Positraction hardware, and drivetrain compatibility agree with records · 1977 Chevrolet Corvette
Where to check: Transmission case or tag, differential, chassis, shifter and linkage, build sheet, and service records · 1977 Chevrolet Corvette