I am building a 550 horse 434 and puting some nitrous on it and in the past the th400 has been very good to me, and the th700 not so much. How hard would it be to switch to a th400 any and all metal fabrication is no problem I am a welder so no big deal. But any info from anyone that has done this would be very helpful and appreciated.

i have heard that you can use the 200C driveshaft with the shorter of the 2wd version of the th400 trannies

and works fine

not sure on the trans mount location

cant remember if the 400 ones are further back or forward than the 700r4 ones

i know the 700r4 ones are further back than the th350/200c/250 are


i forget


good luck!

except that the TH400 uses a different yoke for the driveshaft and has no torque arm provision...and you need a different crossmember...

other than that it ought to be a piece of cake...

If you have the budget for a 434 small block on nitrous, you don't have the budget for the built 700R4 and strong rear end? I guess I can see a TH400 swap because they're tough but I like overdrive.

I have the budget for the built 700r4 but the best one i can find only hold 700 horsepower and thats about to the point i will be and i don't want to ride the fine line of breakage. And I am putting a strange 60 in the rear just curious about the tranny mount and driveshaaft

If you look to the left and click on Spohn performance they sell a nice TH400 crossmember with a torque arm mount on it. The driveshaft is a matter of measuring and going to the driveshaft shop.

200C driveshaft with a TH400 slip yoke is what I'm running. Bought a Spohn crossmember and torque arm combo for the TH400 swap. The crossmember is really low though and I'm going to be making my own.

i used the stock crossmember for my th350....all i had to do was mill the mount slot a lil bit and made a sort of L shaped bracket that came off the x member that bolted to the torque arm

Thanks for all the help sounds relatively easy.