Of all the possible components that can be pulled out of a junkyard and used to make major upgrades to your 4×4, axles are arguably the best. They are easy to inspect and easy to pull, and best of all they’re usually pretty easy to identify.
Most 4x4s come with adequate axles for a stock application, but once you throw bigger tires and a locker into the equation, the stock axles just won’t cut it with many platforms. There are all kinds of possibilities for upping axle beef, from using 3/4- and 1-ton axles in 1/2-ton trucks to cross-pollinating better designed axles from a different make or model into your own 4×4. Junkyards usually sell complete axle assemblies cheap compared to other components, and if you’re lucky enough to find one in good shape with the ratio you want, the cost of an upgrade often isn’t much beyond the price of the axle itself.
Below you will find the specifics on identifying popular axle donors, and in a few cases how to identify axles that you’ll want to steer clear of, when searching for axle upgrades for your 4×4 project.
Identification: Roughly square-shaped differential cover with rounded corners and 10 bolts, 9 inches wide.
Specs: 7 1/4-inch ring gear, 27-spline axles, 2.73-5.13 gear ratios, standard or reverse rotation.
Found In: Front of various Jeep and International applications, plus various IFS versions.
The Good: The Dana 30 is stronger than it really has a right to be considering the light-duty construction and lightweight specifications. Most Dana 30s can handle a moderate tire size increase and a locker with judicious driving, and numerous upgrades are available, including a 30-spline upgrade for several applications.
The Bad: At the end of the day the Dana 30 is a lightweight axle and doesn’t last long with a heavy foot and hard use. Later-model housings are prone to bending with hard use,
Notes: Widely used from the 1950s through 2006, the Dana 30 had various iterations, both driver- and passenger-side drop, and standard as well as reverse rotation.
Identification: Oval-shaped cover with 10 bolts, 10 5/8 inches wide, rubber fill plug.
Found In: Rear of 1987-2006 Wranglers, 1984-2001 Cherokees, and 1993-2004 Grand Cherokees.
Specs: 7.62-inch ring gear, 2.73-4.88 gear ratios available, semifloating.
The Good: Just about nothing. We’re including this axle so you know what to stay away from. There are non-C-clip versions of this axle that can be found in 1987-1989 YJs and 1984-1989 Cherokees that are marginally better than the C-clip versions, but there are all kinds of axle upgrades and gear ratios available. Not that we’re condoning polishing this turd.
The Bad: Weak C-clip axles, weak axletubes, weak gearsets, weak carrier, and pretty much weak everything else.
Notes: It’s really not worth throwing money at this axle, and definitely not worth buying one in a junkyard unless you’re just trying to get back on the road after exploding one you have. Just about any other axle is better. Seriously.
Identification: Roughly D-shaped cover with 10 bolts, 10 3/8 inches wide. Often (but not always), “44” is cast into a reinforcing rib of the differential housing.
Found In: Front or rear of numerous Chevy, Dodge, Ford, Jeep, International, and Isuzu models.
Specs: 8 1/2-inch ring gear, 2.73-5.89 gear ratios, semifloating.
The Good: These are very popular axles for a reason. They are strong and versatile, having been used in many applications. Numerous upgrades are available thanks to such a long history, and with factory axles made in many different configurations, a Dana 44 is a viable swap candidate for many applications.
The Bad: The early axles had coarse 10- and 19-spline axleshafts that are weaker than later versions, and replacement parts are limited for some of these applications. There were also undesirable closed-knuckle Dana 44 front axles in the early 1970s. Both low- and high-pinion front 44s were produced, which can cause confusion when you’re ordering replacement parts. 2007 and newer JK axles are called Dana 44s, but they have little in common with the earlier versions, and JL Dana 44s are completely different yet again.
Notes: One of the most popular axles ever produced, the Dana 44 was used extensively by every OE manufacturer. Both front and rear applications were produced, and front axles could be high- or low-pinion depending on the application.
Identification: Roughly D-shaped cover with 10 bolts, 12 1/8 inches wide. Often (but not always), “60” is cast into a reinforcing rib of the differential housing.
Specs: 9 3/4-inch ring gear, 3.31-7.17:1 gear ratios.
Found In: Front or rear of numerous Chevy, Dodge, Ford, Jeep, and International 3/4- and 1-ton trucks, semi- and full-floating, single wheel and dualie.
The Good: Very strong with a minimum 6,500-pound GAWR, this axle is well supported by the aftermarket. Numerous upgrades are available, including virtually any locker, up to 40-spline axleshafts, and much more. The front Dana 60s came in both kingpin and ball joint configurations. It’s hard to go wrong with a Dana 60.
The Bad: Early versions used coarse-spline axles, and many OE rear applications were 30-spline and not much stronger than a Dana 44 shaft. 1994-2002 Dodge 1-ton applications had undesirable Center Axle Disconnect (CAD) systems, and the castings of some applications make them difficult to adapt to other suspension designs.
Notes: With nearly as long a history as the Dana 44, the Dana 60 was used by virtually every domestic manufacturer at some point and is still in production. Buyer beware when shopping for a Dana 60 front from a 1999 or newer Ford Super Duty, as the Dana 50 looks very similar to a 60 and unscrupulous buyers often try and pass off this much weaker axle as its bigger brother.
Dana 70 & 80
Identification: Roughly D-shaped cover with 10 bolts, 12 5/8 inches wide. Often (but not always) a “70” or “80” is cast into a reinforcing rib of the differential housing.
Specs: 10 1/2-inch ring gear, 3.07-7.17:1 gear ratios, 35-spline (Dana 70) 11 1/4-inch ring gear, 3.23-5.38:1 gear ratios, 35- or 37-spline (Dana 80).
Found In: Mostly the rear of various years of Chevy, Dodge, and Ford 3/4- and 1-ton trucks.
The Good: More or less bulletproof, these axles are pretty much overkill for anything running below 44-inch tires and/or a heavy rig with lots of horsepower. The Dana 70 and 80 are frequently found under the same model and year truck depending on how the vehicle’s options and engine, hence why we lumped them together. Quite a few ratios and lockers are available, though not as many as for the Dana 60.
The Bad: All that strength comes with a lot of weight to match, as well as reduced ground clearance. Gear ratios and axle upgrades are more limited compared to other axles but still acceptable provided you’re not doing something terribly exotic.
Notes: Dana 70s often fetch cheaper prices than the more popular Dana 60 while providing additional strength and are a viable choice for a budget build, especially when purchased with a matching front axle. Though rare, there were some front Dana 70s, but strength in a front application is comparable to a Dana 60. Dana 80s began production in 1988 and can be found in various light truck and even medium-duty applications. Both axles can be found in various industrial applications in addition to trucks.
Courtesy of Dana
Dana Axle ID
There are multiple ways to positively identify a Dana axle, even if it has been separated from the donor vehicle. As mentioned, look for the axle model number cast into one of the reinforcing ribs of the differential housing. The gear ratio tag attached to two of the differential cover bolts will sometimes note the model number but will always have the six- to eight-digit Bill of Materials number as well as notations for the axle’s gear ratio. The ratio is sometimes noted as the actual ratio (e.g., “4.11”) but is usually noted as the number of teeth on the ring-and- pinion that you can divide to get the ratio (e.g., “41 10”). The BOM number will also be stamped somewhere on one of the axletubes (usually the long side), and later axles will often have a paper tag with the BOM that might still be legible. If you are able to find the BOM of a Dana axle, you can go to danamate.com and find out everything you ever wanted to know about the axle, including all of the part numbers for service parts and more. This is very handy information, as seals and other small parts for the same axle model can vary by when it was manufactured and the vehicle it was originally under.
Identification: A roughly square differential cover retained with 10 bolts, 11 inches wide.
Specs: 8.8-inch ring gear, 28- or 31-spline, 2.26-5.13 gear ratios, semifloating C-clip axles, five-lug.
Found In: Rear of 1982-2012 F-150, 1982-96 Bronco, 1991-2001 Explorer, 1991-2011 Ranger (4.0L only).
The Good: One of the most widely produced axles Ford ever made, the 8.8 is an excellent choice for any mild or moderate trail vehicle. They are extremely plentiful and cheap in junkyards while being well supported in terms of gear ratios, differentials, and axleshaft upgrades.
The Bad: Axles are retained by C-clips, enabling a tire and wheel to separate from the vehicle in the event of a broken axleshaft. A few truck 8.8s came with 28-spline axles, so buyer beware. One could confuse an 8.8 with the lighter-duty Ford 7.5, as the cover is roughly the same shape as an 8.8 but is 1 1/4 inches narrower.
Notes: A Ford 8.8 from an Explorer is pretty much the go-to budget axle swap of choice to replace the Dana 35 in several Jeep applications. They are within 2 inches of stock width on XJ,s TJs, and ZJs and have the same 5-on-4 1/2 bolt pattern. Even though the axles are held in place with C-clips, we’ve found axleshaft failures are exceedingly rare, even with stock shafts. If that’s a concern, C-clip eliminator kits are available.
Identification: Dropout-style centersection with 10 bolts.
Specs: 9-inch ring gear diameter, 28- or 31-spline, 3.00-6.50:1 gear ratios, five-lug.
Found In: Rear of 1966-1983 Broncos and 1957-1986 F-100s and F-150s; various cars from the 1950s through the early 1980s.
The Good: The Ford 9-inch is a popular, strong, and well-supported axle. Much of the axle’s strength for its compact size is attributed to a third bearing used on the nose of the pinion that prevents pinion deflection under heavy loads. The sky’s the limit in terms of upgrades, from 31-, 35-, and 40-spline axleshafts to nodular iron housings to just about any popular locker or limited-slip.
The Bad: Early 9-inch axles were plagued with 28-spline axleshafts that are fairly weak, but these can be upgraded to 31-spline without much trouble. The pinion sits low on a 9-inch centersection, making the rear driveshaft a bit more vulnerable than other applications. Last manufactured in the mid-1980s, junkyard 9-inch axles are still out there but getting harder to find. Also, don’t confuse a 9-inch with an earlier 8-inch that was used in some 1960s car applications; the easiest way to tell is that the bottom two bolts on a 9-inch require a socket to remove, while all of an 8-inch axle’s centersection bolts can be accessed with a wrench.
Notes: The 9-inch is an excellent choice because it offers a lot of strength in a lightweight package compared to other axles. The stamped steel housings are lighter than many cast differentials with heavy-wall tubing, and thanks to the aftermarket, a 9-inch can be built to handle just about anything. The initial popularity of the 9-inch is largely due to its dropout-style centersection, which is attractive to drag racers because the design enables quick gear ratio changes.
Sterling 10 1/4 & 10 1/2
Identification: 12-bolt cover, 12 1/2 inches wide, full-floating design (some 10.25 axles were semifloating).
Specs: 10 1/4-inch ring gear (1985-1998), 10 1/2-inch ring gear (1999-newer), 35-spline axles, 3.08-5.38 gear ratios, eight-lug.
Found In: Rear of 1985 and bewer F-250 and F-350 trucks; most common in 1999 and newer Super Duty trucks and Excursions.
The Good: These axles were developed by Ford to replace the Dana 60 and Dana 70 axles and have a good reputation for strength and durability. Though some 10 1/4-inch axles were semifloating, all 10 1/2-inch Sterling axles have a full-floating design.
The Bad: The earlier 10 1/4 axles have a few weaknesses that were addressed with the later 10 1/2 design. There are also some oddball 10 1/4-inch semifloating applications, such as the short-lived, light-duty, seven-lug F-250, which should be avoided. Locker selection and axle ratios are not as good as other applications, and there are some year splits for gears and overhaul kits that anyone should research before ordering replacement parts. Though it’s rare, we have seen Sterling housings spin the axletubes under extreme use.
Notes: These axles have been the primary rearend for Ford’s Super Duty trucks since the term was coined in 1999. Equivalent to a Dana 70 and stronger on paper than a Dana 60, these axles are a good choice and a popular one for JKs on 40-inch and larger tires. Like all Super Duty axles, most Sterling 10 1/2-inch full-floating axles use an 8-on-170mm bolt pattern.
GM 7 1/2-inch
Identification: Squarish 10-bolt differential cover, 8 3/4 inches wide, smooth bottom (no protruding bosses like a 10-bolt).
Specs: 7 1/2-inch or 7 5/8 -inch ring gear, 26- or 28-spline semifloating axles, 2.73-4.56 gears, five-lug.
Found In: Rear of S-10 Blazers, Astro vans, and pickups; various car applications.
The Good: Not much to say here other than they seem to live if you leave them alone. We’ve included this light-duty axle mostly to identify what to stay away from.
The Bad: These axles are marginal for stock applications and will not hold up to large tires and abuse. Differential selection is limited, as is gear ratio selection.
Notes: Unless you’re considering an axle swap into a lightweight vehicle like a Samurai, these are not the axles for your build. Even then, far better choices can be had for about the same money with many more differential and gearing choices.
Identification: Mostly round 10-bolt cover with a slight bulge on the left-hand side, 11-inch-wide cover, two bosses at the 5 and 7 o’clock.
Specs: 8.5-inch ring gear (1979-1998), 8.6-inch ring gear (1999-current), 28- or 30-spline axleshafts (depending on year) semifloating C-clip axles, 2.73-5.57 gear ratios, five- or six-lug.
Found In: Front of 1973-1987 GM trucks and 1977-1990 Blazers, Jimmys, and Suburbans; rear of 1979-2013 1/2-ton trucks (depending on the application); select S-10, Trailblazer, and Colorado applications.
The Good: These axles are reasonably strong and durable in stock applications, but other than that, there’s not much good to say about them.
The Bad: They become marginal when adding bigger tires and traction-adding devices. The front (solid axle) applications are roughly equivalent to a Dana 44 but do not enjoy the same aftermarket support. The rear axles are all a C-clip design, and the shafts themselves are prone to failure when subjected to abuse. Though common, these axles are far from ideal.
Notes: These axles should not be confused with 10-bolt car axles, which have little in common with the truck 10-bolts. History and practical experience have shown that these axles survive fairly well in stock applications, but their shortcomings start showing up as soon as they are modified or subjected to a heavy right foot. With heavier 14-bolt axles being so prevalent and cheap, it’s hard to justify putting any money in one of these axles.
Identification: Irregular 12-bolt differential cover, 11-inch-wide cover.
Specs: 8 7/8-inch ring gear, 30-spline semifloating C-clip axles, 2.76-5.13 gears, five- or six-lug.
Found In: Rear of various 1963-1981 1/2-ton truck applications.
The Good: These axles have a pretty respectable reputation and can easily stand up to 35s and locking differentials with conservative driving. We’ve beat on a few 12-bolts and have been impressed with what they can withstand.
The Bad: C-clip axle design leaves much to be desired, and it’s hard to justify putting any money in one of these axles when 14-bolts are so cheap and plentiful. These axles are also getting harder to find now that square-body Chevys aren’t as prevalent in wrecking yards as they once were.
Notes: Like the GM 10-bolt, the truck 12-bolt has almost nothing in common with the car version of the 12-bolt. They are a mild upgrade to a 10-bolt, but we wouldn’t go through the hassle of swapping one in the place of a 10-bolt unless the axle was free. Still, these would be a viable option if going to eight-lug wheels was out of the question.
Identification: Fairly prominent octagonal differential cover with 14 bolts, full-floating design, single or dual wheel.
Specs: 10 1/2-inch ring gear, 30-spline axles, 3.21-5.38 gears, full-floating axles, eight-lug.
Found In: Rear of various GM 3/4-ton, 1-ton, and 1-1/4-ton trucks, vans, and SUVs from 1973 to today.
The Good: Pretty much the gold standard of axle beef, there are few cheaper or better choices for a serious axle upgrade than the GM 14-bolt. Bulletproof right out of the gate, a 14-bolt needs very little to withstand big tires, big power, and big abuse. With such a long production run and widespread use, it’s hard not to trip over multiple 14-bolts in any junkyard across the country, and we’ve paid as little as $50 for one. Later-model axles even have disc brakes.
The Bad: The large centersection of the differential housing is a low-hanging shovel that hurts ground clearance. The drum brake versions are about 120 pounds heavier than disc brake versions due to the heavier brake assembly. Stock yokes are usually oddball GM-specific U-joints and not standard Spicer 1310/1330/1350 stuff.
Notes: Don’t confuse the full-floating 14-bolt with the lighter-duty semifloating axle with a 9 1/2-inch ring gear of the same name; they have almost nothing in common. When swapping one, consider an axle shave kit because it can significantly improve ground clearance.
Identification: Perfectly round differential cover with 12 bolts, about the size of a basketball cut in half.
Specs: 8 7/8-inch-diameter ring gear, 29-spline semifloating (often two-piece) axleshafts, 2.73-4.88 gears.
Found In: Rear of 1976-1986 Jeep CJ-5s and CJ-7s, and fullsize Jeeps of the same era.
The Good: Though often maligned, the AMC 20 actually boasts a stronger ring-and-pinion than a Dana 44, and most of its shortcomings can be addressed with some fairly simple modifications. The biggest attribute that an AMC 20 has for a builder is that it’s already present; it’s not a good swap candidate into another application in most cases.
The Bad: The stock two-piece axleshafts in CJs are a break waiting to happen if they haven’t already. The CJ centersection castings and axletubes are fairly thin, making them easy to bend. Just about any AMC 20 is going to take some money and time to make capable of surviving moderate abuse.
Notes: Some of the FSJ AMC 20 applications came with one-piece axles, eliminating the need to upgrade them, and the FSJ housings are more rugged than the CJ versions. AMC 20s were also used in quite a few car applications, so aftermarket support and upgrades remain surprisingly strong for an axle with a relatively limited production run.
Chrysler 8 1/4
Identification: Oval-shaped 10-bolt differential cover with a flat section at the bottom, 11 3/8 inches wide, rubber fill plug.
Specs: 8 1/4-inch ring gear, 11 3/8 inches wide, 27- or 29-spline semifloating axles, 2.73-4.88 gears.
Found In: Rear of 1991-2001 Jeep Cherokees and 2003-2007 Jeep Liberties; some early Dodge Dakotas and vans.
The Good: Specific to Cherokees (which is the most prevalent 8 1/4 platform) the biggest thing an 8 1/4 has going for it is that it’s not a Dana 35. While the 27-spline versions are only marginally stronger than the Dana 35, the 1996 1/2 and later 29-spline versions make the axle roughly equivalent to a Dana 44.
The Bad: Though decent, the Chrysler 8 1/4 is really a light-duty axle and is not up to lots of abuse. Gear ratios and aftermarket support are somewhat limited compared to other axles.
Notes: The similar size and shape of the differential cover makes it easy to mistake one with a Dana 35, and vice versa, so be careful when identifying. Other than being a bolt-in replacement for an exploded Dana 35, a Chrysler 8 1/4 is not a good swap candidate.
Chrysler/AAM 9 1/4 Rear
Identification: Hexagonal differential cover with 12 bolts, 12 1/2 inches wide.
Specs: 9. 1/4-inch ring gear, 31-spline semifloating C-clip axleshafts, 3.21-4.88 gears (rear); 33-spline reverse-rotation (front).
Found In: Rear of 1966-2010 1/2-ton Dodge/Ram pickups and SUVs; front of 1994-2010 Ram 2500s.
The Good: The front axles are considered very good and are roughly equivalent to a Dana 60 while becoming easier to find in junkyards all the time. The rear axles are solidly average across the board, but like the GM 1/2-ton axle offerings, the Chrysler 9 1/4 becomes pretty marginal when big tires and lockers are added to the mix. Again, the biggest advantage of one of these axles is that it is present, but it’s not a good axle to swap into other applications or sink much money into it to make it stronger.
The Bad: C-clip axles are known to break when used hard. Differential selection is limited, though gear ratios remain pretty broad.
Notes: Most Dodge truck builders opt to replace these axles with the heavier-duty 3/4- and 1-ton truck offerings from Dana or AAM.
Chrysler 9 1/4 Front
Identification: Irregularly shaped cover with 14 bolts, reverse cut.
Specs: 9 1/4-inch ring gear, 33-spline inner axleshafts, 3.42-4.88 gears.
Found In: Front of 2003-2018 Ram 2500/3500s and Power Wagons.
The Good: Roughly equivalent to the strength of a Dana 60, these front axles have proven to be durable. They are also becoming more common in junkyards with about 15 years of production in very popular Ram trucks.
The Bad: The dreaded Center Axle Disconnect (CAD) that disappeared from Ram trucks in 2003 returned in 2014, so later model axles have a CAD system. Locker selection for this axle is surprisingly limited, with only a few currently available. We’ve also seen these axles spin the axletubes when subjected to hard use.
More Info: Manufactured by AAM, the 9 1/4 was developed as a replacement for the Dana 60 and has proven to live up to the 60’s reputation.
Chrysler/AAM 10 1/2 & 11 1/2
Identification: Irregular shaped differential cover with 14 bolts. The 10 1/2 is 13 1/2 inches tall by 13 3/4 inches wide. The 11 1/2 is 14 1/16 inches tall by 13 9/16 inches wide.
Specs: 10 1/2-inch ring gear or 11 1/2-inch ring gear, 30-spline full-floating axleshafts, single wheel (10 1/2, 11 1/2) or dualie (11 1/2 only), 3.73-4.56 gears (10 1/2), 3.42-5.38 gears (11 1/2).
Found In: Rear of 2003-2013 Ram 2500s (and some 1500s) with gas engines (10 1/2); 2003-current Ram 2500s and 3500s with diesel engines (11 1/2).
The Good: Built as a replacement for the Dana 70 and 80, these axles are heavy-duty and pretty much bulletproof. The 11 1/2 axle is more common, better supported by the aftermarket, and is pretty standard on any late-model Ram with rear leaf springs.
The Bad: The 10 1/2 axle isn’t well supported and is kind of an oddball that’s overshadowed by its bigger brother. The 11 1/2 offers plenty of beef but it is huge and heavy. It is not a good choice for a lightweight buggy, but ideal for a big fullsize truck running big tires.
More Info: These axles are manufactured by AAM, which is actually a division of General Motors. As a result, we are seeing more and more AAM axles replacing the usual suspects under GM trucks, including the legendary 14-bolt.