The early Bronco's front axle is a closed-knuckle (kingpin) Dana 44 from mid-1971 through 1977 — strong enough for 35" tires and moderate trail use. Trucks from 1966 to mid-1971 carry the smaller Dana 30 instead. The Dana 44's weak point is the inner axleshaft U-joint and the kingpin/knuckle seals, all of which live or die on regular service. Keep them greased and inspected and the axle outlasts almost everything bolted to it.
Ford ran two front axles under the first-generation Bronco. From 1966 to mid-1971 the truck used the Dana 30; in mid-1971 Ford switched to the larger Dana 44, which carried through to the end of the run in 1977. Both are closed-knuckle, kingpin designs — the steering knuckle is a sealed ball housing, not the open ball-joint knuckle that appeared on later Ford trucks. The 1976–1977 Dana 44 also gained factory front disc brakes; everything earlier used drums.
Identifying which you have matters before you buy parts: the Dana 44 has a larger center casting, larger U-joints, and (76–77) disc brakes, while the Dana 30 is visibly smaller. If you are unsure, measure the ring gear or count the cover bolts against a known reference before ordering gears or shafts.
Dana 44 key specs:
The Dana 44 front is comfortable under 35" tires and moderate rock and trail work. Past 35", or with an aggressive locker and a heavy right foot, the limiting parts become the U-joints and the open differential rather than the housing itself. Stock gear ratios were 3.50, 3.73, or 4.09 depending on year and engine — and front and rear ratios must match exactly. Once you move past 33" tires, plan to regear; the tire-size-to-ratio logic is laid out in the gear ratio selection guide. For traction, the front axle is the higher-value end to lock on a closed-knuckle truck; the tradeoffs between selectable, automatic, and limited-slip units are covered in the locker options guide.
Inspect the knuckle ball seals at every oil change — a weeping seal is cheap to fix and expensive to ignore. Pull and grease the U-joints at the start of each wheeling season. Re-pack wheel bearings on the 2-year/20k schedule. Pop the locking hubs apart annually to clean and re-grease the internals; grit and old grease are what seize them. None of this is expensive, and it is the difference between a Dana 44 that runs for decades and one that strands you on the trail.
| Part | Vendor | Est. price |
|---|---|---|
| Spicer 5-760X U-joint (front axleshaft) | Spicer | ~$28 |
| Warn Premium manual locking hubs (pair, Dana 44) | Warn | ~$220 |
| Timken front wheel bearing and race set | Timken | ~$60 |
| Closed-knuckle inner axle seal and kingpin rebuild kit | Wild Horses 4x4 | ~$140 |
Written and maintained by an AZ wheeler and driveway wrencher. Always cross-reference your factory service manual — modifications affect vehicle safety and warranty. Work at your own risk.
Trail Manual · About · Privacy · Terms · Database