Okay, kind of an in-depth question, but one I think can be real useful to all HAMBsters. Can someone please explain to me what tailshafts will swap between transmissions in the GM Turbohydro series? I've heard that four-wheel-drive truck transmissions can become two-wheel-drive transmissions and vice-versa simply by bolting on the tailshaft from the other version. Therefore, if you've got a burned-up 700R4 in your hot rod, and somebody offers you a recently rebuilt one from a wrecked 4x4, you can simply swap on your old tailshaft and bolt the thing in your car. Can you crossbreed transmissions, though? Like say a 700R4 tailshaft on a TH350 or is that impossible? Thanks, Dave
Well............not quite THAT simple. Yes you can change that rear shaft and housing, but not without nearly completely diss***emling the ******. I have done many car to 4X4 conversions using the tailshaft from the 4X4 and the case and internals from a car. Now I am talking 350 turbo here. There is a kit available to install a 350 turbo in place of a 700 in a 4X4. It amounts to a shaft and an extention housing, whichs makes up the difference in lenght between the 350 and 700. Not that hard to do in a 350 turbo ******. The cases in 350's were the same lenght. It was the output shaft and housing that differed. Hope this helped
Another difference on many of the Chevy 4x4 housings, is that they use a heavy duty 6 bolt cast aluminum flywheel cover, which is also braced to the front motor mounts. The case is different at the bottom front. But to answer the original question...no, each transmission series uses it's own specific output shaft design, so you can't swap between 350-400-700 types.
i was just reading this, and have a similar question, can i take a tailshaft from a car 700r and use on the 4x4 trans after taking off the transfer case and back of the trans? if so ill just go get a tail shaft off a car instead of the whole trans Ron
For the 3 pedal guys... The saginaw 3 spd with O.D. tail can be adapted to a Saginaw 4 spd to give you and old style 4spd w/O.D.
I have a similar question - truck 1 ton, 2 wheel drive,400 turbo with bolt on yoke. What does it take to convert to p***enger slip joint, or can you just run a slip joint in place of the bolt on yoke?
The tailshafts are internal and you have to do a total dis***emble to swap them, it is not as simple as unbolt and bolt back on. I think most of the 400's with bolt on yokes are really 475's and you can use a regular slip yoke. Those are super heavy duty transmissions.
there is also a "stop" ring that has to be removed to use a slip yolk in this ******...... tail housings are aslo swapable to the 4x4 with this model. as they have the intermediate lenght shaft. there were 3 400 tailshaft lenghts manufactured
Bolt on "yoke" style t-400 trans are not mostly t-475 trans. Dennys drive shaft sells a slip "yoke" that will slide onto a t-400 with a bolt on "yoke" style output shaft. Yes there are '3' different length t-400 4x4 output shaft designs. ....... Early 205 t-case design is simply a short shaft 2 wheel drive shaft. 203 t-case design output shaft Late 205 & 208 t-case design output shaft. A 700r4 trans of the 4x4 design needs a different output shaft to convert to a 2 wheel drive setup. carry on...
I stand corrected as I thought all bolt on yokes were 475's it is also good info on the 700's I wondered if they were able to be changed to 2 wd I gather that goes with the 4L60-E also??
The tailshaft is part of the first ***embly to go into an open case, complete teardown is required. The "offer" better be pretty close to free or you might as well rebuilt what you have. The shafts are interchangable if the speedo drives are the same - reluctor vs. worm - 4wds have a heavier duty case in the bellhousing area, the tailshaft area is the same. Pretty sure no th350 parts will interchange.
ok, good info my situation, i have a good 4x4 700, i can get a 700 from a 2wd but it is no good, ill just tear it down and change the tail shafts and housing thanks Ron
I'm in this situation now with a bolt in yoke trans, now when comparing the two yokes a slip vs. bolt on, the bolt on is about 2 1/2 - 3 inches shorter. Then it's also not splined on the first 3/4 inches. My question is, how does it handel the power without the extra length splines inside the yoke ?
Hey guys I have 2 700r4 trannies and want to know what is involved in changing the speed sensors? I have one geared and one electronic. I need to swap the electronic tail stock to the other ****** but can`t get the metal gear off of the shaft to put it on the other shaft. please help!!!!
Ok guys i got a question, I have a turbo 400 ****** with an np 205 transfer case my ****** went out in my truck i keep finding 2 wheel drive ******s but i need a 4 wheel drive can i just unbold the tail of the ****** and bolt my transfer case right to the ****** and make it into a 4 wheel drive if not what do i need to do.
You need to pull the tailshaft and change it too. Unfortunately that requires completely dis***embling both transmissions. You'd probably be better off just rebuilding the one you have btw welcome to the hamb, don't be surprised if you get some **** for asking about your 4x here....
hey got a quick question gonna need some guidance on this i think im switching a turbo 400 out for a turbo 350 what all will i need to change for this to work I have a 350 small block with a 6 ft bed and a np 05 transfer case but not sure what ill need to do. can anyone help
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