Hey all, I’ve got a VisionLine Challenger that had a bad front driveshaft right out of the box. Instead of shipping it off (out of warranty, second owner but the shipper box was never opened) I decided to fix it myself. I purchased the new driveshaft/dog-bone from Lionel for $12 (part number 6101104035, #50 on the Lionel parts page). Currently trying to figure out how to complete the repair correctly (last picture in this post) but figured this would be a good time to post some pictures and the steps I took to get here, as I couldn’t find much online on opening these up.
I started off by turning the locomotive over and removing the 4 screws that hold the cab to the chassis. Flipping it back to its wheels, I carefully pulled the cab off the chassis and disconnected the wires from the plugs. The smoke units for the smoke stack and the whistle steam stay with the locomotive body.
Next I removed the 4 screws holding the speaker down to the chassis. I pried the wire tab up with a flathead screwdriver just enough to pull the wires out and put the speaker to the side. It’s still connected by a wire but I needed to be able to get underneath it to remove a screw for the front drive wheels. The 4 screws holding down the speaker are different sizes so be sure to keep track of which goes where.
You can see the screw I’m talking about in this picture. Using a flathead screwdriver it removes easily, make sure not to lose the spring and washer where the wheel assembly attaches from the underside. There is another similar screw on the back of the wheel assembly that needs removed from the underside of the chassis (not pictured)
I also removed the screw holding the piece that the blue white and green wires go to, just to get a little extra room. Although it probably wasn’t needed.
I also had to remove one screw from each side of the pivoting tubing that goes to the wheel assembly. At this point there is still some wires going to the wheel assembly (for the headlight) but just carefully move everything around and there’s plenty of room to work. Be sure not to pull on the wires too much though.
Here’s where my issue was. The original driveshaft was missing a rivit/pin that holds driveshaft joint together. I originally thought I could remove the driveshaft/dog-bone from the silver driveshaft using an Allen-key but it seems now that it’s also a rivit/pin so I’m currently looking for options on how to go about removing/replacing this. It seems part #65 would have been the better part to order if you would want to have a bolt-in fix, but it cost 3x as much. I’ll report back on what I used once I figure something out, unless someone has a good idea of what to use for this. 
Other than that, this locomotive is fairly simple to work on if you just take your time when disassembling/reassembling. I’ll get some more pictures of the inside of the locomotive and post them here before buttoning it back up also.
