I'm debating on the purchase of a TH400 to replace my stock TH350 and I'm curious if this will be an easy swap or will it require a shortened driveshaft and/or will I run into fitment problems with the bellhousing being a bit bigger/longer? For the price I can get this for (0 miles on fresh rebuild) and includes a 2500 stall, I really don't want to pass this up. If the swap will require a bunch of work to get it to fit, then it's really not that good of a deal. If I could utilize the knowledge of someone that's done this themselves or knows about this, would be much appreciated. Thanks!

 

The TH400 is a great tranny... but heavy compared to the TH350... it is longer so you would have to shorten the Drive shaft... replace your transmission cross member and come up with a kick down switch since the 400 does not use a Throttle valve cable like the TH350... not sure if you would have problems with the Speedo cable or not but you might have to swap out the speedo gear to match your cars rearend gears.... hope this helps some..

 

Thanks for the insight. With regard to the cross member, are you positive that it would need replacing? The reason I ask is because that was my first question to the owner. I was informed that he had this trans mounted in the car ('79 Camaro) with the original c-member. Wasn't sure if that was BS or not. I need a new speedo cable anyway as well as drive/driven gears. Removing the cruise control and had the rearend work done last fall so that was planned already.

 

Not 100% on the cross member... but I thought it was longer... ask a few here who have Big block and 400's in their car for sure...

 

We have a Big block with a 400 and we're using the stock crossmember. The c/member has slots where the mount bolts to the member. should clear.