th350 swap for 700r4

[Stitch]

I have a 6.2 diesel with a 700r4 behind it. My 700r4 won't shift now and I need two vehicles so I have to fix the truck. I have a th350 sitting in the garage that came behind a 305 stock. I need to k is what I need to make it work for right now. I'll eventually get another 700 but right now I just need my truck. I know I can move the tranny crossmember. And I know the driveshaft will work and the cooler lines will work. I need to know about the vacuum hookup. I read it needs vacuum in order to shift. Also I heard that because it's behind a 305 the stall speed should be close enough. At least for now. I really need to know quick. Thanks guys. I also have a th400 but read that's alot more work. Thanks fellas
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[D13]

Assuming you have the correct length trans and the truck is not lowered or raised such that the driveshaft will bottom out or fall out of the trans>>>
You need the vacuum regulator valve from the IP of a TH400 equipped truck (CUCV etc). It replaces the TPS switch on the side of the IP. For a kick down cable you'll have to use the TH350 cable and the 6.2's TV bracket and rod (the TH350 cable won't reach the IP) (since 6.2's and TH350 never came together) and plan to have some shift point issues because the geometry will be wrong. It'll either downshift on light throttle or not want to upshift on light throttle (I disremeber which way the geometry works out). You may be able to adjust it with rod length to a 'normal' driving setting but I think the hard throttle downshift will be off. BTW you can expect a relatively short life of a TH350 converter behind a 6.2, they don't like the vibrating pulses.

You can run a th350 with no vacuum but it'll think your at WOT on the 305, and the shift points will be way beyond the 6.2's rod kicking RPM.

Other option is just hook it op to the vacuum pump directly and drive real gentle since the line pressure will be low and the shifts early and soft.

[Stitch]

I can deal with it shifting low and easy. I just need to get the truck driveable so I have two vehicles
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[benoit454]

if it's a 9 inch tail th350 it'll bolt right in place same ds, same linkage same mount all of it.

vac. is easy just tap into a manifoldd or full time vac. source maybe even t into something. Not sure as to what on a diesel though. the kickdown cable if you get the short end one that's made like the end of the 700r4 it will hook right up to and work well. Or you can just leave it unhooked it's for passing gear and you can manually downshift it. The cable you would need would be for a newer vehicle with a th350c most likely, as in mid 80's truck or car from chevy with a th350c or if they say yea we have them 2 different lengths, the shorter one is it.

The linkage works fine, od is d and d is 2 then so on. I did the same thing to my 88 truck it had a 350 tbi and 700r4, I put in a th350 behind the tbi350.

[D13]

Diesel's don't make engine vacuum, that's why the vacuum pump and swithc are needed to simulate a gasser. But full vaccum will keep the line pressure and shift points low.

Might check here for a switch package: http://dieselplace.com/forum/forumdisplay.php?f=20

Then go look at the for sales or post a need.