All graphics and text pertaining to the axle
identification chart were obtained and reproduced by Colorado K5 with prior written
permission from fourwheeler.com
These Danas are indistinguishable in appearance. The military Model 25 has a thick, cast
cover, while the 27 and civilian-model 25s have a thinner cover, will accept taller gears,
and backed V-6s.
The alloy-case Dana 28, with a 6 5/8-inch-diameter ring gear, came in Bronco IIs and
Rangers with anything but the 4.0-liter engine. Although 4.0-liter trucks come with Dana
35s, most of the front suspension and/or drivetrain needs to be swapped to replace a 28.
The Model 30, with a 7 1/8-inch-diameter ring gear, was the standard front differential in
some 1972-75 CJ-5s and all 1975-and-later CJ-5s and CJ-7s. It is still used in the front
of Cherokees and Comanches, and will probably appear in the front of the Grand Cherokee.
This axle, with a 7.56-inch ring gear, is the fronted for 4.0-liter Ford Rangers and
Explorers/Mazda Navajos. The 35C version is found in the rear of Cherokees and
The 41, which has a ring gear size similar to the Dana 44, came in early CJ-2As. The
spiders are the same as a 44's, but the carrier and gears aren't. It is almost universally
swapped out in favor of a Dana 44.
All domestic manufacturers have used Dana axles, and the 44, with its 8 1/2-inch ring
gear, is likely to be a step up on anything smaller than a 1/2-ton. A narrowed 44 could be
the hot ticket for vehicles smaller than a full-size sport-utility. It was standard under
the front of pre-1976 Chevy Blazers and 1/2-tons, solid front-axled F-150s and Broncos,
and Jeep J-10/J-20s and Grand Wagoneers.
The Ford-version Dana 44 Twin-Traction-Beam setup is similar to other 44s (ring gear
diameters are identical), but there are no axle tubes and the "cover" is
actually the suspension arm. It's standard in the front of any TTB-equipped Ford except
the 1987 and newer F-250HD, which uses a Dana 50.
A Dana 60 looks deceptively similar to a Dana 44, but the 60's 9 3/4-inch ring gear
diameter is a major factor in strength. It can be found in many 3/4-ton pickup and van
Almost identical in appearance to a Dana 60, the Dana 70 is standard in heavy Dodge
pickups and GM duallies. The large 10.54-inch ring gear diameter will tolerate much
torque, and is suitable for diesel power and/or big tires.
The small Ford rear end, which sometimes uses a fiberglass cover, is found in Bronco IIs
and non-4.0-liter-powered Rangers. For bigger tires and/or engines, it's usually swapped
for a Ford 9-inch.
The 8.8-inch debuted in 1983 Broncos and F-150s, and is now found also in 4.0-liter
Rangers and Explorers/Navajos. It is easily distinguished from a 9-inch by having a cover
on the back.
The venerable Ford 9-inch is both readily available and strong. Later models have bigger
axle tubes and stronger housings. It was standard under 1966-88 F-150s and Broncos. It
also came on many vans and the Lincoln Versailles (a popular axle for swapping because of
the Lincoln version's disc brakes with parking brake).
Ford's biggest axle comes with semi-floating shafts in 1983-and-newer F-250s, and as a
full-floater in F-250HDs and F-350s. Applications are similar to the big GM 14-bolt and
the Dana 70.
The GM 10-bolt is named for the number of bolts on the cover; ring gear diameter is 7 1/2
inches. Variations of this can be found in the rear of GM S-trucks and some
Isuzus, and in
the front of S-trucks.
This 10-bolt, with a larger 8 1/2-inch ring gear diameter, replaced the Dana 44 that was
used in the front of some pre-1977 GMs. It can also be found in the back of 1983-91
1/2-tons and in the front of 1983-87 1/2-tons.
The stronger 12-bolt, with an 8 7/8-inch-diameter ring gear, can be found in various
1964-82 GM 1/2- and 3/4-ton rearends.
The "small" GM 14-bolt has a 9 1/2-inch ring gear diameter. It was used in the
rear of 1964-and-later GM pickups, and in the rear of 1984-91 3/4-ton
With a 10 1/2-inch-diameter ring gear, the biggest 14-bolt GM rearend looks much like a
Dana 70, and is but a few thousandths of an inch shorter in ring gear diameter. This axle
is commonly used with big engines and/or overly large tires. It was used under 1973-87
Used in 1976-and-later Jeep CJs, the Model 20 rearend is both strong and weak. An 8
3/4-inch-diameter ring gear provides strength; weaknesses are the housing itself and the
axle-to-hub retaining method. Converting to one-piece axles or full-floaters gives this
axle better stamina.
Mopar's 9 1/4-inch rearend can put a stop (notice the octagonal stop sign cover shape) to
rearend woes on many lesser-equipped vehicles. Chrysler has used these since 1969, on 1/2-
Close to eight inches in ring gear diameter, this rearend has been used on 1979-and-later
4Runners and pickups. The four-cylinder turbo and 1988-and-later V-6 models have larger
side carriers and the same ring size in front.