Okay fellas, I have been working slowly on putting together a new drivetrain for the Peterbilt. I have no problem with the Wedico 3 speed, but space is tight on this model, and I'd like to have more room for other features. Thanks go out to my friend Rick, who introduced me to the compact and tough as nails Banebots planetary gearboxes. He was one of the first guys to use one on a truck and it looked perfect for my intentions! I'm giving up a 3 speed transmission for a single speed that is stronger and smaller, which is a big help. I really want to keep the interior of the cab, and the Banebots gearbox, with a standard 540 motor will entirely fit beneath the cab floor.
Can't say I've ever heard of anyone tearing up a Wedico 3 speed in a truck application, but they have had some failures in the heavier Wedico 966G Cat. If we take a peak inside, just because I like seeing how things work, we can see some plastic gears and a belt drive reduction.
Other then the plastic gears and the belt, everything else does look pretty beefy, but for now, the trans is being pushed off to the side for this....
I've got a Novak 55 turn motor, mounted to the Banebots P60 planetary box. It's running a 20:1 reduction and feeds my new transfer case, from RC4WD. I did the math for calculating the gearing and I should end up with the truck being about as fast as it would be in 2nd gear, if I used the 3 speed trans. If I run a little more then 12 volts, I should pick up a little more speed, or I can always swap the motor to a 45 turn. Something I couldn't do with the Wedico trans, as you are stuck running a Buhler motor, wether or not you like it. Can't change the pinion gears either, at least not without some custom machining.
I did have to turn down the output shaft on the planetary box. As it comes, it's about .5" in diameter! Huge. I turned it down to a more common 5mm size and milled a flat on the shaft for the set screw to grab.
Here's a picture of the internals. This is only one stage of reduction. The 20:1 box uses two stages, but this is what it looks like. Just add another stage of planetary gears behind the other, and you'll have it. You can also see the shaft I turned down more clearly. It was huge! The bearings that support it are also monsters. It was intended for robots, so it can take some serious load.
Another picture, showing how it goes together.
Finally, one shot of the RC4WD transfer case I will be using. It's a 1:1 ratio, so it provides no reduction, but it looks really scale, and cool. Intended for scale rock crawlers or trail trucks, but it will be right at home inside the Wedico. I just need to machine up some mounting brackets for both the transfer case and the planetary gearbox, and I'll be all set.