TH350 1 pc driveshaft question

[68c10owner]

I currently have a 700R4 in my truck that is on its last leg. A buddy has a TH350 I can pick up cheap. Last time i did this I used the driveshaft out of my 65 chevelle but never measured it and that car is long gone. Does anyone have the measurement?

BTW, before anyone asks why I`m going to a th350, its only temporary. This is my only vehicle so I need to put the th350 in while I have the 700r4 rebuilt then swap back. A lot of work yes, but since its my daily I have to do what I have to to get by.

[Project86]

If you have a short tail th350 and it should be fine using your original driveshaft if I remember correctly. If you go from a long tail to a short it won't work. But i could be wrong...I read it somewhere just would have to search the forums again

[68c10owner]

Th 350 and 700r4 are different lengths so I don't see how the driveshaft would be the same length for both transmissions.

[Project86]

Just found my source. If you have a long tail th350 you can use the original driveshaft on the 700r4

[Chaplain]

Originally Posted by Project86

Just found my source. If you have a long tail th350 you can use the original driveshaft on the 700r4

Yep...me too on the swap and me too on using the same driveshaft. However, I'm staying with the 350.

[Project86]

Good deal. My 292nd gear in my th350 went out so I may go with the 700r4 here soon

[Axle]

When I did my 700r4 to th350 swap I used a long tailshaft (9-1/4") th350 and my original one piece driveshaft. You can figure out the difference when you get your donor th350 and measure its tailshaft.

Alex.

[68c10owner]

Thanks for the input guys. Helpfull info. I'm not sure what tail shafts it is but I'm guessing it's a short shaft. I haven't looked at it yet. I need to have everything ready to go before I do the swap because this is my only vehicle and I won't be able to have any down time. I can do the swap in less than a day so it's a weekend project.

[65standard]

Center to center of u-joints is 55 1/4" on my 1985 C/10 with factory installed 350 trans. Note that my trans is a long tail.

[68c10owner]

Originally Posted by 65standard

Center to center of u-joints is 55 1/4" on my 1985 C/10 with factory installed 350 trans. Note that my trans is a long tail.

So for a 6" short tail shaft I`m guessing I`d need a 58 1/4" shaft? My trans went out last night so I`ve got to get this swapped over the weekend and I cant find a trusted 700R4 anywhere. I just cant spend $500 on a used one and hope that it works. I know this Th350 works and its free.

[65standard]

Sounds about right.

[68c10owner]

About to start the swap. I`m going to get the TH350 in there and then take a measurement. I did several searches and came up with several different measurements for the same 117" wheel base trucks. We`ll see how it goes.