I have a 1960 Ford f-100 that has a small block chevy in it. I had a turbo 350 transmission behind it, and im trying to swap it with a turbo 400. Im not sure what i have to do to complete the swap. So i'd like any help, advice, or personal experience that any one may have. All help will be appreciated.
One thing you need to determine is whether the flex plate to torque converter attach holes are the same or not. It may be necessary to change drive (flex) plates. If that is the case, the 400 drive plate may have a different tooth count and require a different starter mounting housing. As mentioned by the previous poster, the trans is longer, requiring the mount/crossmember to be moved rearward, the 400 output shaft has a larger spline than the 350, requring a different yoke and the shaft will have to be shortened. Cooler lines, linkage etc. should be easy. Sorry for the "maybe's" , but these are potential areas of attention. A tranny shop can probably answer these questions in about two minutes. Ray
Leave the TH350 in it. Lots less work and takes less horsepower to turn. If you are swapping it out because it's bad they are very easily rebuilt for about $200.00. Tim
the problem is that i'm short for money so i am going the cheapest way to get it running, and i love doing the work.
Have you priced out getting a driveshaft shortened, re-yoked, and rebalanced yet? Probably cheaper to rebuild the TH350 yourself, depending on whats wrong with it. Think it through... There are two different yokes for the TH400. One is fully splined, the other only halfway splined. Make sure you are using the correct one for your transmission.
Then the cheapest way to get it running IS to rebuild the 350. Add it up: Rebuild kit for 350 = about $150 clams. No special tools needed, just a vise and a couple C clamps. New driveshaft = $200 New trans mount = $25 Buy TH400 = $??? Fix TH400 = $??? because you are probably buying a "pig inna poke", and there is a reason it is for sale. Oh, yeah, it's just as much work either way, mostly. Cosmo
First thing, what lenth TH350 do you have? The 6" and 9" extension housing are the most common. What lenth TH400 do you have? Most Chevrolet are the the short lenth. Now, the 9' extension TH350, and the short TH400 are fairly close; in this case the 400 is actually shorter. I just used a longer slip yoke to compensate in my 3/4 ton Chevrolet truck. You most likely have the short TH350 and the short TH400, meaning you'll have to shorten your existing driveline; or hit the wrecking yards to find one of the right lenth, or close, and use the correct slip yoke. Flex plates can be redrilled, it's the crank bung that centers them; a new mount and crossmember is easy. My final word of advice, once you drive it with the TH400 you'll be completely sold, and will probably never want a TH350 again. That was my case, so I went out and bought another TH400 just to have on hand. No more weak sprag, lag shifting, or poorly timed shifts. Butch/56sedandelivery.
You should be able to find a driveshaft without making one,or having one shorten shouldn't be that expensive,but relocating or replacing the crossmember and other thing make costly.Why not 2004R, same length move crossmember back,lots of info on them in here?
they are both short shfts and i kinda have my heart set on doing the swap so i was thinking about goingto a junk yard for a drive shaft
moving the cross member is not a probem due to the fact that the frame rails are straight. just relocate, drill new holes and go. plus the tranny came with a torque converter and a yoke. I do know that the th350 torque converter has a 1 1/2 '' bolt circle and the 400 has a 11 1/2 " bolt circle so i would have to change flex plates
NOT ALL T400's are longer, my daily 81 el camino was a easy swap, just moved the crossmember mount, and changed yokes, i used a t350 torque converter
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