Replace or Rebuild Transmission

[MegaOlds]

I have a dilemma on my hands and I figured you tech heads would be the best place to ask for help.

Right now I have a TH350C in my Cutlass and it is leaking from (2) locations. The front pump and another spot on the passenger side. Now I can drop this transmission and have it repaired, rebuilt or I can leave it as is and work on this TH400 that I just bought from a close friend for 80 bucks. It needs rebuilt. So with this being said...

Do I spend the money and get the TH350C repaired/rebuilt or should I focus on the TH400? I am aware with the TH400 that a different yolk/driveshaft will have to be used. Any and all help is appreciated. Thanks!

Note: Most of the shops around me, Springfield, IL, want anywhere from $800-$1200 to rebuild the TH400 so I've been thinking about doing it myself. I am well aware of what it takes to rebuild it. I feel confident I can do it myself but would rather have a shop just take care of it.

 

[mac61891]

I think it would depend on the rest of the car. Have you got a higher HP power plant or is it fairly stock. I would do one or the other, not both, for sure. The 400 would be a lot stouter. And dollar-wise, about the same to rebuild. If engine upgrades are in the works, then the 400 would be the way I would go. Just keep adding fluid until the 400 is ready to go in.

 

[MegaOlds]

It's not a high horsepower plant but I would eventually like to do heads and cam.

 

[axisg]

Food for thought. The 350c is a lockup trans, the th400 is not. Although not a lot of fuel savings it is noticeable. To swap the 400 you not only need to switch driveshaft yolk but the crossmember as well. For my money if on a budget I would get a th350, bolt it in place and go. Or if the funds allow ( say $1500 - $2k ) swap it out to either a well rebuilt 200r4 or 700r4 trans with OD from a known vendor like Bowtie, ArtCarr, Extreme, CK, ect.... The 200r4 will bolt in place using your existing driveshaft but you will need the 4sp shifter, driveshaft, and tv cable brackets. The 700 requires a little more fab work to fit but are just as good when built esp if you like a really low 1st gear.

 

[MegaOlds]

Well from what I understand, the 400 is a stronger transmission. I eventually want to put a 455 in there so I would like to do the 400 and be done with it.

 

[lilbowtie]

Well from what I understand, the 400 is a stronger transmission. I eventually want to put a 455 in there so I would like to do the 400 and be done with it.

Axisg brought up a lot of good points and you can build yourself a stout 350 trans. With that being said I'm a 400 fan - It does take a little more HP to turn it but in my years of racing I haven't had one fail yet. Sounds like you are going to add some HP and willing to do the rebuild yourself which I would suggest it. It is a very easy trans to work on (along w/ the 350) I would suggest a book by Ron Sessions (How to build an modify the turbo 400) I've built 6 of them and a couple w/ trans brakes.