Thread: 1937 Dodge Pickup with 350 Turbo, want an overdrive tranny

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I'm finishing a 1937 Dodge pickup built on a 1989 S-10 frame with a 1989 350 and an older 350 Turbo. I want to upgrade the tranny to a 700r4 or any other overdrive tranny that will work. What would be the best way to go? How about the overall length and trans mount location compared to a 350 Turbo.

Here you go.

700r4 to th350 Swap

The legnth difference may vary depending on the TH350 tailshaft legnth you have.

I don't know if it will be an issue for you, but when I revised my plan and decided to use a 518 OD instead of a 727 my 37 Dodge PU I found I have to redo my floor pan due to the increased size of the transmission case.

If you have a truck th350 with the 9'' tailstock, the driveshaft won't need to be cut.
The crossmember will need to be moved for sure.
The case should be about the same physical size to fit the tunnel.

If you have some room to spare between trans and tunnel, especially the rear 1/3, it should fit. The 700 is a little larger further back. Towards tail end. And as said the trans mount is further back, 1 1/2 to 2" if memory serves. I went the other way once. I had a bad 700r4 in a suburban and put a 9" th350 in it's place. In that case I just made a plate to extent trans mount forward.

I thought I read somewhere that the 200-R4 was about the same length and mount location as the TH350, I could be wrong about that. Is your 350 V8 a real high output motor or more of a stock/mild build?

My dad and I are doing a similar truck build but we are using an 82 S-10 and a 41 GMC pickup.

I've heard both good and bad things about 700r4's, what's up with that?
I'm looking for fuel economy and reliability, got a stock 350 at maybe 200 hp, would a stock setup 700 work?

My nephew has destroyed at least 2 hooked up to a used up 305, something about the cable adjustment, is that the one connected to the carb? What's so important about it?

A lot of it has to do with TV cable adjustment which regulates the internal pressure,improper adjustment will smoke the 3-4 clutch pack first and then the rest will self destruct.You can Google 700R4 TV cable adjustment and be able to find setup info,after doing the base adjustment you should then get to a nearby transmission shop and do the final adjustment with a pressure gauge.The year of the donor transmission is also important,1987-92 are non-computer and also have the best factory internal mods,1986 and earlier 700R4's and 2004R's should not be considered for a build.

Size chart:

TCI - TECHNICAL INFORMATION: Transmission Dimensions