| Year & Model | Axle Length | Notes |
| 1965-1966 Mustang | 57.25 inches | |
| 1967-1970 Mustang | 59.25 inches | |
| 1971-1973 Mustang | 61.25 inches | |
| 1977-1981 Versailles | 58.50 inches | |
| 1967-1973 Mustang, Torino, Ranchero and Fairlane | 59.25 - 61.25 inches | |
| 1957-1959 Ranchero and Station Wagon | 57.25 inches | |
| 1966-1977 Bronco | 58 inches | |
| 1977-1981 Granada/Versailles | 58 inches | |
| 1967-1971 Comet, Cougar, Mustang and Fairlane | 59.25 inches | |
| 1971-1973 Mustang | 61.25 inches | |
| 1964 Falcon | 58 inches | |
| 1967 Cougar | 60 inches | |
| 1967 Fairlane | 63.50 inches | Coil springs |
| 1972 Ford Van 3/4 ton | 68 inches | |
| 1973-1986 Ford Van 3/4 ton | 65.25 inches | |
| 1957-1959 Ranchero and Station Wagon | 57.25 inches | narrowest 9" housing |
| 1966-1977 Bronco | 58 inches | 5-on-5 1/2 inch diameter bolt circle |
| 1967-1973 Torino, Ranchero and Fairlane | 59.25 inches or 61.25 inches | |
| 1967-1971 Comet, Cougar and Fairlane | 59.25 inches | |
| 1975 Mustang II 8" | 57.00 inches | |
| 1974 Maverick 8" | 56.50 inches | |
Where To Find The Nine Inch Rear Axle1967-1973 medium and big block Mustangs and Cougars
1966-1971 Fairlanes, Torinos, Montegos, Comets, and other Ford intermediates with big blocks
1957-1959 V8 Fords and Mercurys
1977-1981 Lincoln Versailles & Trucks
Types Of Nine Inch Axle Housings1967-1973 Mustang/Cougar - light duty, thinnest housing material, small axle bearings, 28 and 31 splines.
1957-1968 passenger car and 1/2 ton truck - medium duty, stronger than Mustang type, 28 and 31 splines.
Ranchero/Torino - heavy duty thick wall housing, 3.25 inch diameter axle tubes with flat tops.
1969-1977 Galaxies (coils), Lincolns (coils), and late pickups (leaf)- 3.25 inch diameter all the way to the backing plate, coil housings have upper control arm mount
How To Recognize Nine Inch Housing Centers1957 - no dimples, flat center band up the center of the rear cover, bottom drain plug.
1958-1959 - two dimples on back of housing, flat center band, some had drain holes.
1960-1967 - two dimples, flat center band, oil level hole in back cover.
1963-1977 Lincoln, LTD, Thunderbirds had 9.375 inch centers, housings were cut away at the gasket surface for ring gear clearance, one curved rib at the front top portion of differential, strong but no gears.
Tip On Shortening Nine Inch Axles1972 and earlier 31 spline axles have the ability to be shortened.
28 spline axles are tapered and cannot be shortened and re-splined.
1973 and later cars have a 5-on-5 bolt circle and the axles cannot be shortened.
1967-1973 Mustang axles can be identified by wheel flange:
Oval hole = 28 splines.
Two large holes and counter-sunk center = 31 splines.