transmission advice

[vivajo]

th400 transmission
Any recommendation on a ready to bolt in mail order ? basically stock 348 - or find a used one and have it rebuilt

 

[425/409ER]

Lots of performance places sell the turbo 400's but now they charge a ton of $$$. In the last 2 years I have been give 3 free turbo 400's. I rebuilt 2 as they had some issues, and the other one was a full manual valve body one that I got "free" and it works. Buy a core at a swap meet, go to YouTube and watch some videos on how to rebuild them, they're pretty easy to do inc. putting a shift kit in them. As for recommendations, Jeg's Summit and local transmission shops will have them, but without a core you will pay more. I know the 2 I mentioned don't need cores but it's built into their prices.

 

[Jim Sullivan]

A turbo 350 might be a better choice behind a stock 348. And less expensive/readily available.

 

[wristpin]

A turbo 350 might be a better choice behind a stock 348. And less expensive/readily available.

And better gas milage

 

[427John]

I agree, I don't see a stock 348 requiring the services of a Turbo 400, unless there are plans for future significant power upgrades then it makes sense to do the Turbo 400 now.

 

[johnnyriviera]

Also a TH350 has lower first and second gears....little more oomph accelerating. Robs less power too.
TH350 can be built plenty strong for your application.

 

[dakota tom]

There is very little different in gear ratios. Th350 is smaller and easier fit depending on the chassis

 

[IMBVSUR?]

350 also. I agree with 425/409er. These are basic rebuilds that almost anyone can do if they have general mechanical abilities. Purchase what is known as a compliance kit. It will have most of what you need unless you have hard part damage or want upgrades. Those performance shops are high prices rip offs in my opinion. I am not saying they don't work, I am saying you can get the same thing in Sacramento for a half the price at a good shop. A shift kit can also be advantageous. If you get a good core, I could probably recommend a good builder in your area that would do a side job reasonably.

 

[Skip FIx]

My 10.90 Trans Am has a TH350 in it, but somewhat built. Wore out a stock rebuild when I was just in the mid 11s. But it held up until then! my 400 hp 400 ci motor pounded on a stock rebuild for years. The 455 hurt it.

 

[SSpev]

I'm with you all. Defiantly a th350 over the 400

 

[425/409ER]

I'm with you all. Defiantly a th350 over the 400

Wait until the sprag assy. breaks on a turbo 350, then you can appreciate a good Turbo 400.

 

[lmpala58]

Any thoughts on the tr200 on a 348

 

[lmpala58]

Sorry I meant 200-4r on a 348

 

[lmpala58]

Sorry I meant 200-4r on a 348

 

[La Hot Rods]

I think they are a good fit. I have rebuilt a few of those but was never impressed with internal parts. I know they build these to take a lot of HP for Gran National guys that race them.

 

[lmpala58]

Yes - no money in it so if I need to spend a little might be ok- heard the gears are a little better than the 400

 

[La Hot Rods]

They do have a good gear spread plus the overdrive and lockup torque converter.
I'm sure they make them with just the Chevy bolt pattern but all I have seen are the universal bellhousing that are kinda ugly if your looking that close.

 

[lmpala58]

Thanks I will check the bolt pattern- I thought they were the same as the power glide

 

[Mr. Chev]

I like the t400 for one reason, durability, its just a damn good transmission, best choice, maybe not, good gm transmission you betcha!

 

[La Hot Rods]

They are good but a tight fit in an X frame car.