Toyota Axle Swap - Won Ton AxlePosted in How To: Transmission Drivetrain on May 21, 2014
Toyota mini truck axles find their way under a lot of projects due to their light weight, excellent ground clearance, and strong aftermarket support. That said, they still have their limitations. Mini truck front axles are narrow (55 inches WMS to WMS), the factory Birfields are weak, and they use a low-pinion third member. The aftermarket has solutions for all of these issues, but what if we told you that there was a factory Toyota axle that was wider, had larger Birfields, and came with a high-pinion third member? Add in drive flanges for optimal trail abuse strength and an available locker as an option from the factory, and you have a winner. Such an axle exists, and it came under the front of ’91-’97 80 Series Land Cruisers.
While this seems like the perfect axle, swapping an entire 80 Series axle was a more daunting task … until now. The issue was that the factory suspension and steering arrangement on the 80 did not lend itself to swaps. The stock suspension uses coil springs and radius arms that run under the axle, with the tie rod behind the axle running under the high-pinion third member. This puts the tie rod in the way for most link or leaf-spring suspensions.
Billy Weiss from Hellfire Fabworks was not deterred though; instead of a roadblock he saw an opportunity. Hellfire makes complete replacement knuckles for the 80 Series axle that are stronger than stock and include high steer arms with Dana 60–sized studs. We couldn’t wait to get our hands on a set and put them to the test.
To complement the knuckles, we called JT Parts to order a 5.29 Nitro Gear & Axle ring-and-pinion, new Birfields, and a complete rebuild kit to make our 80 Series axle better than new. Read on to learn more about why you could consider using an 80 Series axle in the front of your next project.
The stock 80 Series suspension uses coil springs and radius arms under the axle. The steering arms are mounted on the bottom of the knuckle with the tie rod in back and the draglink in front.
The first thing we did was cut off all of the factory bracketry with our Miller Spectrum 375 plasma cutter. The stamped housing makes it easy to add custom brackets for your suspension, once you address the factory tie rod location.
Bayshore Truck made these clever mounts for Toyota and Ford 9-inches which allow them to bolt the third members into a vise to perform diff work. If you set up a lot of differentials it is worth making something similar.
80 Series axles use drive flanges that attach to the hubs with studs and cone washers. A brass drift is the easiest way to get the cone washers to unseat and remove the flange. Manual locking hubs can be swapped in place of the flanges, but the Birfields needs to be machined to accept the proper snap ring location.
Nitro Gear & Axle uses high-quality Koyo bearings in its master install kits, ensuring that your differential runs cool and quiet. These are the same bearings that Toyota uses from the factory.
Starting with ’02 models, Toyota replaced the 27-spline pinion in its 8-inch axles with a 29-spline pinion. Most aftermarket manufacturers require you to retrofit the weaker 27-spline design, but not Nitro.
Ninja star? No, this is the oil slinger found on the pinion of the Toyota high-pinion third member. It is crucial to ensure that the bearings stay lubricated at sustained speeds.
To match the 29-spline pinion, we ordered a new pinion flange from Nitro (left). The new flange is drilled with multiple patterns to accept most Toyota drivelines.
The 80 Series Birfield (left) is significantly larger than the standard mini truck Birfield. In addition, the axleshaft does not neck down on an 80 Series where it enters the Birfield.
Nitro offers chromoly Birfields and axleshaft for 80 Series, but we used the company’s stock replacement Birfs to save some money. The factory Birfields had excessive play since the axle seals had worn out and allowed gear oil to mix with the grease in the knuckle. This is a common problem on 80 Series.
Here is the Hellfire knuckle next to a stock FJ40 knuckle. The Hellfire parts make stock components look like toys. The biggest addition is the real estate on top of the knuckle that allows the addition of high steer arms.
In order to keep costs down the Hellfire knuckles reuse the stock lower trunion caps. Bayshore cut the steering arms off the caps using a horizontal band saw and then cleaned them up with a belt sander.
The Hellfire Fabworks knuckles accept the factory steering stops, brakes, and lower trunion caps but have added material for greater strength when compared to the factory knuckles. They also use a set screw to set the preload of the trunion bearing, making this process much easier than the stock knuckles.
Your Dana 60 arms mount with five studs? How cute! The Hellfire steering arms use six Dana 60–sized studs and tapered nuts similar to lug nuts to keep them from loosening on the trail.
The Hellfire Fabworks steering arms come with inserts that allow the user to customize the steering to place the tie rod above or below the arm depending on the application. We will weld the inserts into place after the axle is under our project vehicle.
The completed axle is ready to swap under our next project, so look for it to make an encore appearance in the magazine soon. The weight, width, and strength make the Hellfire- and Nitro-equipped 80 Series axle a great choice for a lightweight trail rig. At 285 pounds this axle is comparable in weight to a Dana 30 but with strength approaching a Dana 60.