Chevy TH350 Transmission stout enough?

[SherrysOldBus]

We're starting to build our 66 chevy blue bird 24 footer, 7 window, (48 passenger), and wondering if a TH350 trans will survive for awhile or instantly implode with the weight...guessing around 10,000 lbs with a gas V8 engine.

[cadillackid]

TH350 is a great transmission but i wouldnt use one in a full size bus.. you Might get away with a TH400.. however the lack of lockup and only 3 gear ranges really inhibits how well a bus will drive..



if it were my build I'd probably go with either a good stout manual.. or if you want an auto go wit ha good BUILT 4L60 (yuo can do an E wit has standalone controller)..or even a standalone control and a 4L80E... bith of those can be built really stout and retain the lockup feature.. being they are overdrive you can run a bit lower ratio rear gear which will help you get things moving off the lione or climb better in the hills..



both of those transmissions also have lockup converter abnd can be locked up in as low a gear as second.. a 4L60 (heavy duty built) can run with just a lockup control (its mechanical otherwise)...


id stay away from the 200 series and probablky the 700 (even thoigh the 700 later became the 4L60.



again you can probably build a 350 to be stout but if im gpoing to put $$ and effort into a trans build id build something thats heavier to start with..

[SherrysOldBus]

Thanks, I really appreciate that info. And will head that way when it’s time. Just now trying assemble a plan for the various departments on the build. 👍🏼😊

[La Camioneta]

Grab a 6.0/6L80E combo w/ecm from a Chevy Express van.

https://www.psiconversion.com/ for a new harness and they will reflash the pcm for your tire height/axle ratio and remove VATS. IIRC its a 2-3 wire hookup, get the fuel pump relay option and you're golden.

You'll need a fuel tank with efi pump, maybe you can find a salvage yard tank that works in your available space.

[La Camioneta]

And the accelerator pedal.

[SherrysOldBus]

Great idea to consider. Is this wire drive or cable? Years are best ?

[La Camioneta]

Originally Posted by SherrysOldBus

Great idea to consider. Is this wire drive or cable? Years are best ?

Looks like anything after 2003 is DBW.

Car-part.com is a salvage yard search engine, look for the inventory you want and see if the yard will do a whole takeout package for you. Looks like engine and trans separate can be had for $4k, ecm price unknown. And you might get dinged for cores.

A whole wrecked van or pickup would also work.

[SherrysOldBus]

Okay, here's a thought??? If I had good old school traditional v8 that I'm confident in, can I just connect it up to the 6l80e and all be happy??????

[La Camioneta]

Originally Posted by SherrysOldBus

Okay, here's a thought??? If I had good old school traditional v8 that I'm confident in, can I just connect it up to the 6l80e and all be happy??????

With a standalone harness/tcm yes. Probably need a cable to electronic tps and some other goodies - though a straight 6.0/6L80e would be easier.