Early Bronco Dana 44 Axle Shaft Upgrade Guide
The 1966-1977 Ford Bronco Dana 44 axle is a popular upgrade for off-road enthusiasts and restorers. While strong and reliable, the early Dana 44s have some limitations, including small 260x U-joints and, in some years, drum brakes. This guide explains your options for upgrading axle shafts, installing stronger U-joints or CV axles, and selecting compatible replacement parts. Whether you’re looking for aftermarket chromoly axles, RCV CV axles, or using stock Ford parts, this page covers everything you need to know to strengthen your early Bronco Dana 44.
The 1971-1977 Dana 44 is a desirable axle, but has to shortcomings:
- 1971-1975 Dana 44 axles have drum brakes.
- 1971-1977 early Ford Bronco axle shafts have small 5-260x u-joints.
U-Joints
One of the major drawbacks of an early Bronco Dana 44 is it’s small 260x u-joints. You’ll need to replace the axle shafts in order to swap to a larger (stronger) U-joint.
Above: 260x u-joint (left) versus a 760x (297x) u-joint (right)
Below: 760x (297x) u-joint cap (left) versus 260x u-joint cap (right)
Replacement Axle Shafts
Due to the Dana 44’s popularity, there are aftermarket axle shafts and axle shaft kits to upgrade your Dana 44 with stronger axles, larger U-joints, and even CV joints.
RCV CV Axles – RCV Performance Ultimate CV Axles simply replace your Ford Bronco’s weak Dana 44 U-joint axle shafts with a high-strength constant velocity design. Tests prove Ultimate CV Axles to be twice as strong as OEM axle shafts, and they’re just as tough at a straight angle as they are at extreme angles – where U-joints are weakest. Ultimate CV Axles also eliminate U-joint binding to allow smooth transfer power to the ground. Even if you have big tires and big power there are no worries. Ultimate CV Axles are low maintenance and operate with a smoothness you can feel – whether off road or on the street.
Yukon Axle & Gear Chromoly Axle Kits – High quality alloys and the latest in heat-treating technologies provide for a strong axle for off-
road.
Yukon YA W24130 – Their W24130 kit includes inner and outer 4340 Chromoly axles and Spicer U-Joints.
Yukon YA W24132 – Their W24132 kit includes inner and outer 4340 Chromoly axles and Yukon Super Joints.
These can be ordered from Randy’s World Wide, Rigid Axle or at:
Other companies offer more economical kits such as:
Upgrading With Stock Parts
If you want to upgrade to larger u-joints, but don’t want to purchase new custom axle shafts, you can use the short driver’s side from an 1973-1979 Ford F100/F150. These shafts have the larger 297x U-joint. The F-150 shaft is 18.90-inches (18-29/32″) long which is 0.59-inches (1/2″) longer than the early Bronco shaft. The 1977-1979 Ford F-150 supercab’s list the driver’s side axle shaft as 18.625-inches (18-5/8″) long, which is only 0.3125-inches (5/16″) longer than the early Bronco shaft.
However, the 1969-1978 Chevrolet Dana 44 Pickup / Blazer (right) front axle shaft is 18.31-inches (18-5/16″) long, so it would work as a better replacement than the F-150 shaft. Also, a Dodge W100 from 1972.5-1974 with BOM 603413 has the exact same length shaft at 18.31-inches (18-5/16″). Both of these shafts use the stronger 297x U-joint and are the same length as the early Bronco Dana 44 shaft.
There isn’t a stock replacement shaft that will work on the passenger side of your early Bronco Dana 44. You will have to get a longer Dana 44 shaft and have it cut down and resplined. Your other option is to buy a new Dana 44 passenger side axle shaft that takes a 297x U-joint.
You will need the matching 9.72-inch (9-23/32″) outer (stub) shafts to accept the larger u-joints.
1971-1977 Ford Bronco Axle Shaft Lengths:
- 1971-1977 Bronco Drivers Side Axle Shaft Length 18.31-Inches (18-5/16″) long – 30 Spline
- 1971-1977 Bronco Passenger Side Axle Shaft Length Length 27.94-Inches (27-15/16″) Long – 30 Spline
- 1971-1979 Bronco Outer Axle (Stub) Shaft Length 9.72-Inches – 19 Spline
Ford Dana 44 Axle Shaft Lengths
760x vs 297x U-Joints
You will likely see some aftermarket axle shafts for your early Bronco Dana 44 that take a 760x U-joint. The 760x is the stock replacement part number for the old 297x U-joint.
The left half is a 760x u-joint – the right half is the old 297x u-joint
The cross of the 760x is cold-forged, while the 297x is hot-forged. The cold forging makes for a denser product. Under cyclical bench testing, the new 5-760X outlasted its 5-297X predecessor by 10 times. While this doesn’t mean that the new U-joint is 10 times stronger, it does mean it’s 10 times more durable.
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About The Author
Jim Oaks is the founder of The Ranger Station, one of the longest-running Ford Ranger enthusiast communities on the web. He has spent over three decades owning, modifying, repairing, and driving Ford Rangers on the street, trail, and cross-country routes.
Since launching TheRangerStation.com in 1999, Jim has documented thousands of real-world Ranger builds, technical repairs, drivetrain swaps, suspension modifications, and off-road tests contributed by owners worldwide. His work has been referenced by enthusiasts, mechanics, and off-road builders looking for practical, experience-based information rather than theoretical advice.
Jim’s hands-on experience includes long-distance overland travel, trail use, drivetrain and axle upgrades, suspension tuning, and platform comparisons across multiple Ranger generations. The content published on The Ranger Station is grounded in first-hand experience and community-verified data, not marketing claims or generic specifications.