350 turbo to 400 turbo

[chevy murf]

So I took out my transmission because it was blown from the guy who sold it to me. This whole time I thought it was a 700 r4 but it turns out the engine is a 350 v8 so the transmission is a 350 turbo. So I got that completely wrong but what I needed help with is that a buddy of mine told me I could get a 400 turbo transmission and put it in no problem with it lining up and everything and that this transmission is alot stronger than the 350 so I want to do that. But before I did wanted to get some advise from you guys. My engine is a 350 v8 can I put a 400 turbo on there???? Or should i just stick with the 350 turbo???

 

[RetroC10Sport]

You can install a T400, but you will need to add a kickdown switch, a different driveshaft and move the crossmember back some.

 

[kleedus]

why is your tranny a 350 because the motor is a 350?

if it has 4 gears neutral reverse and park it is a 700r4

the 350 had both a turbo 350 and a 700r4 behind it in half ton trucks


did I read that wrong

you will need the right t case for the 400 the turbo 350 and 700r4 t case will not fit the 400

 

[Swims350]

th350 to 400 is NOT a direct line up swap, NOTHING is EXCEPT for NOTHER TH350.

a 700r4 and a th400 are longer then a th350.2wd or 4x4 since you are going from the bellhousing area to the tailshaft.

splines are different going into the t-case, so yea not a direct swap. And yes a th400 is stronger but you ask hot rod pc it's gonna take more engine power to turn it over compared to a th350.

 

[foamypirate]

th350 to 400 is NOT a direct line up swap, NOTHING is EXCEPT for NOTHER TH350.

a 700r4 and a th400 are longer then a th350.2wd or 4x4 since you are going from the bellhousing area to the tailshaft.

splines are different going into the t-case, so yea not a direct swap. And yes a th400 is stronger but you ask hot rod pc it's gonna take more engine power to turn it over compared to a th350.

I know we are talking 4x4 here, but since you mentioned 2WD, a 700R4 will actually exchange perfectly with a 9" tailshaft TH350. I've swapped both ways in my 84', from TH350C to 700R4 to TH350. Same driveshaft, mounts, etc.

 

[HotRodPC]

Are we for sure talking about a 4x4? He says it's a C10, not a K10? And true, just cuz it's a 350 motor does not make it a Th350. For 86, it SHOULD BE a 700r4. And if someone has swapped in a Th350 in place of the 700r4 which is common, and that Th350 is bad, I'd rebuild the Th350. I personally like a Th350 better than a Th400 for a few different reason. I would NOT run a Th400 unless I had good reason to need the added strength. Not sure what you consider ALOT stronger. A Th400 is stronger than a Th350, but I don't call it ALOT stronger. With a mild 350 motor in a half ton truck, my choice would be the Th350 all day long unless I wanted to give up some strength to have the OD and lower first gear. That's JMO opinion though. Sounds to me whether you have a 700r4 or a Th350 in the truck now, that's the one you need to have built. Just sayin'

 

[Swims350]

ok then if you want to get real technical then...

a short tail th350 will go right in place of a 3 speed Saginaw or 4 speed Saginaw and most likely a Muncie m21 or m22 and the likes in a 2wd. I've exchanged a 3 spd. Saginaw for a 4 spd and then put a short 6 inch tail th350 in it's place, direct bolt in, mount crossmember location and all.

Now for a 700r4 and th350 I'm pretty sure the mount location on the trans is an inch or so off between the 2 but I forget.

Also with the right length tailshaft, not housing a th350 can replace a 700r4 4x4 trans perfectly. I've did it in my 88.

ANY th350 in place of a 700r4 BUT you must have the spacer to go between the tail housing mount and t-case and THEN the correct length shaft itself, kits are out there to purchase and have the spacer and shaft both in them.

 

[HotRodPC]

ok then if you want to get real technical then...

a short tail th350 will go right in place of a 3 speed Saginaw or 4 speed Saginaw and most likely a Muncie m21 or m22 and the likes in a 2wd. I've exchanged a 3 spd. Saginaw for a 4 spd and then put a short 6 inch tail th350 in it's place, direct bolt in, mount crossmember location and all.

Now for a 700r4 and th350 I'm pretty sure the mount location on the trans is an inch or so off between the 2 but I forget.

Also with the right length tailshaft, not housing a th350 can replace a 700r4 4x4 trans perfectly. I've did it in my 88.

ANY th350 in place of a 700r4 BUT you must have the spacer to go between the tail housing mount and t-case and THEN the correct length shaft itself, kits are out there to purchase and have the spacer and shaft both in them.

Yes, Shorttail Th350 WILL REPLACE a Saggy 4 speed and Muncie M20, and M21. Same length with bellhousing as the 6in short Th350 tailshaft, and same 27 spline output shaft also. This also goes for Powerglide. No need for driveshaft mods even. And yes, on 2wd, the 9in tailshift Th350 will replace the 700r4.

Have we decided yet, is this a C10 or K10 truck. His info is showing C10 which 2wd.

 

[Swims350]

his other thread he started was for a 4x4 truck though and th350 trans with a 4x4 shaft in it.