BJ42 Steering Knuckle Rebuild – Part 1

I’ve been working on getting the BJ42 Landcruiser ready for our upcoming 6,000 mile trip. I noticed the front steering knuckles were leaking axle fluid pretty badly a few days after I topped off the front differential lube. I knew this couldn’t be a good thing so I spent some time researching it in the best Landcruiser forum on the web. I quickly learned I had a big, filthy, greasy job to look forward to.

I don’t really get why the Toyota engineers designed the steering the way they did. It seems heavy and overly complex compared to more modern designs. It appears to be as strong as a tank though so maybe that was the inspiration.

I’ve never had to remove cone washers before. What a PITA. The cone washers that hold the 4WD selector hub onto the wheel hub are very troublesome. If I ever have to dig into the front end again I’m going to switch these hubs to aftermarket units that don’t use the stupid cone washers.

The steering on the solid axle 4WD Landcruisers like our 1982 BJ42 uses a birfield joint to drive the front wheels. A birfield is a type of CV joint that’s completely encased in an external housing commonly referred to as a steering knuckle. (You can see the birfield hanging on the end of the axle shaft in the first photo above.) I’d never worked on a birfield knuckle before so I did all the reading I could on the subject on the web and in the Toyota factory service manual.

The Toyota factory service manual shows the complete procedure and makes it look easy. Of course it specifies the use of Special Service Tools, or SST for short. I prefer to think of SST to mean Super Special Tool because they aren’t useful for anything other than a single specific task. The one tool that I knew would make the job easier was SST 09606-60020 (Steering Knuckle Bearing Cup remover.) I wasn’t going to go spend a bunch of money on a Super Special Tool so I made my own from some parts at the hardware store.
My SST is a couple of 2 inch long 1/2″ bolts with a coupler and a jam nut. It almost duplicates the functionality of the Toyota SST perfectly. You can see in the photo above that it’s basically a press that pushes outwards to unseat the bearings and top and bottom plates on the steering knuckle. The plates are almost off in the photo. This little $2.50 gadget greatly simplified the task of getting the knuckle housing off of the axle.

When everything was disassembled all the parts from each side went into their respective 5 gallon buckets. Notice the two ziploc baggies in the photo below. They contain the top and bottom shim stacks for each knuckle housing. It’s very important that the shim stacks be installed in the same locations on the correct sides of the axle. They are essential for maintaining proper alignment geometry.

The next step was to clean everything up in preparation for the rebuild process. The parts were filthy with old grease, axle lube and road grime. I had some old gasoline that was no good for running in anything so I used it as a solvent to clean the parts. It’s been a few hours and a half-dozen hand washings and my hands still stink like gasoline. It wasn’t the smartest thing to do but at least the parts are clean.

The previous owner must have spent some time in the water with our BJ42. He also must not have been diligent about maintenance. There’s rust and pitting on some of the internal surfaces in the steering joint that show that water got into places it shouldn’t have.
I cleaned these surfaces up the best I could with a brass brush wheel on a drill and followed it up with some 320 grit sandpaper. I paid special attention to the surfaces that make contact with the backside of the knuckle where the wiper seal stack goes. I’m putting in all new seals and want them to last so smooth surfaces are important.

I’m going to leave all of the parts I cleaned outside tonight to air dry. The gasoline fumes are still pretty strong. I don’t want them wafting into the house from the garage. Tomorrow the reassembly process begins. I think I can get it all buttoned up in one day. I’ve got new birfields for both sides and plan to save the old ones as spares. Now that I’ve been through this once I think I could replace a birfield out in the middle of nowhere if one broke on me.