86 c10 Driveline is too short

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Billys44s

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Hey guys

I recently bought a th350 from oreillys for it to turn out to be Th350c transmission.
My Square originally had a regular th350 short tail in it then it was swapped a few years back to a used 700r4 and last year the 700r4 lost 3-4 so I went ahead and bought a brand new trans to put a end to the headache and when I got home I realized this th350 was different from the original the truck had in it.

long story short it turn out to be the th350c and I went ahead and used the yoke out of the 700r4 and after getting everything installed, the drive as barely off maybe about an inch and I’m stumped on what I could do to make it work.

I have the original yoke from the th350 that came factory in the truck but idk if it would fit or give me the length I need to make the drive line work.

any help will be appreciated
 

Rickf

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What about having a driveshaft made up?
 

Billys44s

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What about having a driveshaft made up?
I’ve thought about having one made but I haven’t got a quote on one, I thought since it had a th350 originally that the drive shaft should go in without a problem or is there a difference in length between th350 and the th350c driveline?
 

78C10BigTen

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I wanna say yours probly had the intermediate shaft length (6 inch) originally. Ive been through 4 th350s in my c10 and all are 6" tails.
 

Billys44s

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I wanna say yours probly had the intermediate shaft length (6 inch) originally. Ive been through 4 th350s in my c10 and all are 6" tails.


I would say your correct. I never really measured the original but I knew the tail shaft looks identical to the one down below, I think the 700r4 I had was a 6 inch tail too but it was a tight fit to mate the driveline to the rearend. This Th350c is the old ball because is just barely off from fitting and I have no idea why,if it supposed to be the correct trans for the truck why the driveline is off it puzzle me because I’d figure a 6 inch would be a direct swap in Since that what it had originally

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C10MixMaster

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You have 2 different things going on . First the difference between a th350 and a th350c is the C has a lock up torque converter. C has nothing to do with overall length. TH350th/350C transmissions came with 6"9"12" tail housing depending on application. my experience is trucks got the 9" and vans got a 12" . A turbo 350/350C with a 9" tail housing is about 30 5/8" and a 700r4 is about 30" (unless its a corvette model) .

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78C10BigTen

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You have 2 different things going on . First the difference between a th350 and a th350c is the C has a lock up torque converter. C has nothing to do with overall length. TH350th/350C transmissions came with 6"9"12" tail housing depending on application. my experience is trucks got the 9" and vans got a 12" . A turbo 350/350C with a 9" tail housing is about 30 5/8" and a 700r4 is about 30" (unless its a corvette model) .

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You brought up a point here, i miss spoke. My th350s were 9" tails
 

59840Surfer

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350 Stroker to 383 with a 400 crank, Crane Cam, Q-Jet, single 3.5" exhaust..
" (ibid) ....... so I went ahead and bought a brand new trans to put a end to the headache <snip> "
Where did you buy as "brand new trans(mission)"?

Brand new transmissions are usually wrapped inside a brand new vehicle and I have yet to find any brand new ones (except for the ZF-Fords*) in all my 55+ years as a mechanic that were any more then Rebuilt, Reman'd or Used.

* I ain't going there.
 

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