odonnell

Torque tube - transaxle bellhousing:



Anyone ever seen that one before?

I was fixing to drop the trans and it has me worried. Here's one for you more experienced guys, sorry it's lengthy but it's weird:

I was driving about a few weeks ago and suddenly I hear a whirring, wailing noise from the rear end and I lost power. I was just in 3rd, in light traffic and pulled over. CV joints checked out. Starting in 1st, 2nd, etc all resulted in no movement, just that noise.

My gut told me the diff failed which made sense since it happened in all gears, so it was either the coupler, input shaft, or final drive (and how often do you hear about coupler shearing splines in an NA car relative to diff failure). I had to be back in Waco for finals, so the car sat in Houston until I got back a few hours ago with a new trans.

Here's where it gets weird. I proceeded with caution upon inspecting the cracks, and was removing the coupler allen bolts. I took out the front-most bolt first, and when I was taking out the back bolt the coupler spun over the torque tube splines, as though they had sheared. There was little resistance - I could turn the coupler by hand despite the torque tube not moving at all.

I put the front bolt back in, and it coupled fine, no shearing (from the torque I could apply with my wrist at least). I wish I could say I slid back the coupler to inspect everything, but I never got the second allen bolt out because I broke the only extension I had that would allow me to reach it (someone had the coupler locked down too close to the trans...)

Heading out on a tool run in the morning, hoping to get feedback and pointers on this, I'll update as I progress.

One final thing - I'm still pretty sure the diff failed, regardless of the torque tube condition. I had both rear wheels up in the air, and with the trans in neutral, I spun one wheel. The trans is LSD so the other wheel should have spun, and it did not. Greatly needing a sanity check, and other ways I can verify the state of the diff without tearing the trans apart (although I plan to later on).

Dougs951S

if both tires dont spin when one is spun with the car in neutral, that means the diff took a hike.

morghen

Make sure you take detailed pictures.

I've seen something similar happen to a 993.
Diff died and locked up the gearbox, the input shaft sheared off.

odonnell

Confirmed - splines on torque shaft are sheared down AND diff failed.

jeffrsmith

That's a bummer, actually more than a bummer, but you are going to fix it aren't you?

odonnell

Absolutely. Just need to find rides everywhere to get parts, since the 944 is my only car...

Sterlingx2011

I have a TT and a trans out of an 87 that I have been trying to get rid of. Just Sayin.

odonnell

Have a trans and a friend is spotting me a TT. Thanks though!

931guru

Never have a 944 as your only car.

It makes a pretty good second or third car.

odonnell

Yeah, working on that one. In about a year I'm going to be buying a second car.



Anyway, I've elected to use a grinder and cut the tt bellhousing open and cut the old coupler in half. It's all being replaced.

odonnell

Now that the TT is out, you can really see the cracks and how they contributed to the failure:

kens_74911s

Looks like that Tranny had some trauma that passed the load into the bellhousing. Any accidents on that chassis?

odonnell

Not that I know of. It was tracked before I bought it, and judging by the dog ears on the TT is isn't stock my early car. I'll be making sure the replacement driveline never needs replacement (knock on wood) because this job is pretty annoying.

Arominus

Been doing it for years, now i've graduated to having 2 of them. You know, a spare 944 for my other 944.

I did cheat for part of it, i had a truck for an extended maintenance i did on the S last year. That was by choice not need though.

OakRZB

It only took me 3 Porsches and 15 years to figure this out....