Th350 to th400 4x4 3/4 ton

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Battlac40

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Previous owner switched from a th350 to a 400, front-shaft looks 2in too short .
Sound about right ?
 

HotRodPC

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What year is this truck? Unless it's an early square, it should have been Th400 from the factory if it's a 3/4 ton.
 

Battlac40

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It's not it's a Frankinstein
1/2 ton factory 76
73ish 3/4 ton axles
14corp in the back
D44 in front
205 tcase
Th400
Swb stepside
 

Battlac40

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James
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1981
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K1500 Sierra Classic
Engine Size
350
Big hubs / front
Full float rear
 

HotRodPC

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Ahh OK, Another Franketruck !!! Then there's really no telling for sure because the Tcase would have been changed too since th350 is 27 spline and 400 is 32 spline. So then which adapter does it have and going from which Tcase to which Tcase matters too. As in general, yes the Th400 is a little longer than the Th350 for the case where the tailhousing or Tcase adapter would go, so it does make sense the front shaft could be to short and the rear probably was to long.
 

Battlac40

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1981
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K1500 Sierra Classic
Engine Size
350
Using the flat crossmember,
Guy hacked the back together with a dodge yoke (sitting at ujoint Inc getting a 1350 yoke welded on properly ) but front shaft is sitting in the bed if the truck about 2 inches too short, hard to measure with one hand. Front shaft is an awkward bitch to hold and measure with 1 hand.
 

Battlac40

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New Mexico
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James
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1981
Truck Model
K1500 Sierra Classic
Engine Size
350
The distance is about from the tip of my finger to my middle nuckle (2in). Told the shop to make it 2in longer.
With the slide on the shaft and 2in longer I hope it fits. Not the optimum measuring procedure, I know. But I want it fixed and don't have help.

I read the 350 is half an inch shorter but I think that is the 2wd case.
I think I recall the tcase adding 2in.
But the 2+1 seems too long.
 

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