With a good solution found for one problem, I turned my attention to the next. The lift axle. I had this spare steering axle laying around, and it looked like it would make a nice lift axle. As a bonus, I figured maybe I could even make it a self steering lift axle. The knuckles were already there....
What I ended up doing was narrowing the stock steering axle down quite a bit. I milled a center section right out of the axle and bolted it back together. I had some spare 4 links laying around, which I used to locate the axle and allow it to have way more travel and float then the old set-up. Rock crawler guys will now just how great 4 link suspensions are.
In order to locate the lift axle, I machined an upper 4 link mount for it out of aluminum. The mount is captured between the axle halves and it's very strong.
Plenty of downward travel - more then I really need. My driveshaft will limit that some, once it is installed.
Good articulation, for those off road treks too!
Raised up. Lots of clearance, if I do need the room as well.
And down.
Couple more photos, from the side and angle.
One from above. Yet to come is a lift mechanism of some sort. I'm going to go with a really simple design. Hopefully something as simple as a cable and winch system, or maybe just a servo to raise and lower the axle. I'd like to do air bags, but I'm afraid they would limit the travel and articulation. We run these scale trucks in a non-scale world, and expect them to handle some pretty tough obsticles at times.