Mr6spd

My friend is modifing his 86 vette, and I have a question related to drive shaft length. When swapping a Dana 36 for a 44, does the driveshaft length or U-Joints have to change?

The answer to this question will help us in a round-about way. The issue at hand is that he has a T56 6speed out of a 94 firebird that he wants to put in his 86 4+3 manual vette. We know that the T56 is identical in length to a 700-R4 automatic, so a driveshaft from an automatic C4 might be the ticket to make this work, depending on the answer to the axle question above (since auto's never were paired with Dana 44's as far as I know).

:chevy

BlackRocket

The way I understand it, the drive shaft is a different length in the 6-speed than in the automatic.

Mr6spd

The ZF 6speed OEM in the 89-96 vettes is a different length than the auto tranny, thus necessating a different drive shaft. But the T56 firebird transmission is the same length as the 700R4 automatic.

Thus the question is does the pinion yoke on the Dana 44 axle extend farther forward than the yoke on the Dana 36 axle?? :flag

CFI-EFI

As is evidenced by the different lenghts of the "C" beams, the 44 carrier is longer than the 36. It stands to reason, because the ring gear in the 44 is a larger diameter than the 36. I know of one guy that did a 36 to 44 conversion without changing either the "C" beam or the driveline. He re-drilled the "C" beam in the closer location to bolt to the 44 diff, and was able to wedge the driveline in, unaltered. It looked to me as though the driveline had little or no slip left, and I would be leery of such an installation. Since you are using a trans the same length as the 700R4, driveline wise it is the same as a rear end swap. It MAY go, but after a trial fit, you may be more comfortable having it shortened an inch or so. Good luck.

vader86

you will have to try it and see if it fits.

KLLRVET

A T56 will be a LOT of work to put into a Corvette. it also handles less torque than a ZF. It may not be a good choice.
Tony

tan85vet

I am interested in doing this conversion also...there is a T56 out of a 97 camaro that is available (yes i know the bellhousing is for the LS1). I would like to know what other problems you have run into so far. How did you get past the shifter location?

93Polo

The F-body T56 is rated at 400 ft/lbs. iin the 93s and the 94+ are 450 ft/lbs. tq. The late ZFs are 400 and the early ZFs are 450. Also the T56 is much cheaper to rebuild. I would take a T56 anyday over the ZF, but it will be a pain to drop in a C4.

-=Jeff=-

with the driveshaft vs Trans question...

it is the Dana 36 or 44 that determines the driveshaft length.. so If you have the Dana 44 int he car now.. that driveshaft should work.

HTRK-1

I believe the 97 camaro was an LT1 and some had LT4's.

93Polo

97 was the last year of the LT1 in the F-body. A very few SS's and Firehawks came with LT4s.

tan85vet

I guess its my mistake....it must be a 98 then....I know it has the bellhousing for the LS1.

CFI-EFI

Jeff,
You are absolutey right. After my BIG discussion above, it all boils down to what you said. I don't know about manual transmission lengths for all of years, but if I have interpeted what I have read, correctly, the early years 4+3 is the same length as the 700R4. The difference in the drivelines and "C" beams is due to the different lengths in the carriers. The next problem is where to attach the "C beam to that Firebird trans. I stand corrected.

Mr6spd

Thanks for all the info guys. We were able to measure both the 4+3 and the T56 today, and they are the identical length! Therefore we can use the existing 4+3 driveshaft as is. This swap should be relatively easy, welding up an adapter for the torque arm will be the hardest part.