I've got both and have never rebuilt a tranny so which one would be the better to learn on? Thanks.

I personally think the TH400 goes together easier.
The Th350 will require a tool to compress the low/reverse piston return springs.

Not really much difference either way though.

Either one you decide, get the HP Books manual by Ron Sessions and an ATSG manual.

Cost is about the same too..

Where do you get the tool for the TH350? Avg cost?

Is the 700R-4 much different in terms of difficulty?

Thanks!!

My dad and I rebuild my th-350 this summer. you can rebuilding without any special tools but having them makes everything sooooo much easier and quicker.

I learned on the th350 about 14 years ago. Tool made by OTC for the low/rev clutch was about $65 back then. Many different designs available nowadays, so cost is still similar, due to competition. Having access to a lathe is nice, you can turn down the pistons to add clutches fairly easily. Buy the book, whichever one you decide to do. Around here, a basic kit for a th350 can be had for about $90.

I think the 400 is easier
I really hate sticking the input shaft\drum assy back in a 350
but aside of that really they are about the same