10,000-Mile Review: Dana 80 Rear Axle After Our 4x4 Swap
We’ve put about 10,000 miles on our 4x4 swap, which means our rebuilt Dana 80 rear axle has seen the same. It's time to check in and evaluate what’s worked, what hasn’t, and what we might change in the future.
In this post, we’ll take a critical look at our modifications and maintenance choices to see how everything is holding up — and share our plans moving forward.
Modifications
Gearing
With 315/75R16 tires, we're running around 2,100 RPM at 60 MPH. That’s a bit higher than I’d prefer for highway cruising, but the lower gearing is great for slow-speed dirt road travel, which makes it a worthwhile trade-off for our use case.
Locker – Eaton Truetrac
Going with the Eaton Truetrac was 100% the right call for this build. It has performed flawlessly in every condition we’ve thrown at it.
Wheel Bearing Nuts
You can’t put a price on the peace of mind that comes from knowing you're not going to lose a wheel on the highway. These were a simple but essential upgrade.
Spring/Shock Mounts
As expected, these press-formed steel mounts are doing their job without issue. No surprises here.
ABS Mods
The ABS modifications were a bit of a black hole—we weren’t sure if they’d work or if we’d end up disabling the system through programming. Thankfully, our DIY tone ring and sensor mount have held up. No issues to report.
Maintenance
We completely rebuilt the Dana 80 rear axle from wheel to wheel, replacing nearly every wear item—except for the drums. Here's a list of the components we swapped out (links to each part available in the full parts list):
Brake shoes
Wheel bearings
Inner race Timken 45220
Inner bearing Timken 39585
Outer set Timken SET 38
Wheel bearing nuts Stage 8 X-lock
This rebuild gave us a solid foundation for long-term reliability.
Key take-aways
After 10,000 miles, there’s nothing we’d change about our Dana 80 rear axle setup. I’ve considered upgrading from drum to disc brakes, but the current brake system has performed well. I also thought about going to 5.13:1 gearing, but the benefit doesn’t seem worth the cost or effort at this time.
The Eaton Truetrac has exceeded expectations in every situation. We’ve driven this axle across the country, through the Canadian Rockies in winter, and even ferried it to remote islands — never once doubting that it would get us home safely.
If I had to do it all over again, I’d choose this same axle without hesitation.
What’s Next?
Next up: we’ll dive into our front axle build — what we chose, how it's performing, and what’s on the horizon.
Stay tuned!
