JDcrawlers Messageboard

Need a transmission case for a 420 crawler. Casting number is: 4002T

cement floor is the way to go. used to work at a rock quarry we always just put down a 2x8x12 when we backed the crawler in so we wouldnt chip anything up. biggest dozer we had was a D11 and floor held up well. a smaller crawler should be okay with out the boards.

cement floor is the way to go. used to work at a rock quarry we always just put down a 2x8x12 when we backed the crawler in so we wouldnt chip anything up. biggest dozer we had was a D11 and floor held up well. a smaller crawler should be okay with out the boards.

Thank you Ben for the input. I was thinking both tracks turning but just wanted to ask. We are going to replace the case and pinion gear.... hoping we can find replacements at a reasonable cost.

another question.... when i was breaking the tracks yesterday and trying to get the king pin in the right spot both tracks were spinning even with the crawler in neutral, both tranny and reverser. no clutch or motor in it. i wasnt sure if this was normal or if i had some more underlying problems.

i would definately feel better with a new case in there. would it be okay to only replace the pinion gear?? i checked the ring gear out and it looks prefect.

so we start tearing into the crawler and realize that the back right hand side of the tranny case was broken and very poorly rewelded. they put some pieces of flat bar inside and then tried to weld it in from the top. the rear plate was also cracked and rewelded. So what is the general opinion, try ...

okay thank you. I will just have to tighten those ones down then.

it has the model 61 blade.... sorry I guess I forgot to include that.

Okay here is the first question of this build. Does anybody have some pics of how the blade frame attaches to the rear axle? My crawler has just one u bolt on each side and they are pretty loose. Any help would be great.

Also does anyone know of where I could find a service manual in pdf form?

What a great site!! My Grandpap and I just picked up a 1957 420 5 spd 5 roller crawler. UC is real solid, previous owner was going to restore so he pulled the motor had it redone but never put it back together. So we have a disassembled brand new motor, pretty nice problem to have. I will post some ...