groppo

Oh no, here we go again........to the mechanic. I put my foot down to pass some normal cars and BANG! Something far from normal happened. Loud grating noises were coming from the transmission tunnel. There was no drive at all, but the engine idled okay. After turning engine off and on again the grating noise was still there and no drive at all. There was no visible oil leak anywhere. Has the transmission given up the ghost, or is the torque tube the culprit? And lastly, could it have been caused by lack of maintenace?

Cheers,

groppo

Nicole

Drive shaft in torque tube broken? Or maybe an axle fell off?

When you put the transmission in P - does it "lock" the car in place, or can you move it back and forth?

j.kenzie@sbcglobal.net

Torque tube failure? Use search function for graphic pictures of violence.

Mrmerlin

Hey thats a great question Nicole

groppo

I didn't specifically check car in "P", but I'm pretty sure it locked. There was no drive in reverse aswell and all the noise was coming from the transmission tunnel, ie, below radio.

groppo

dr bob

Nicole's question locates the failure at the driveshaft in front, or perhaps the final drive/half-shafts in the rear. It also assumes that we are talking about a car with an auto trans. I guess there's an 80%-plus chance that it is, statistically, but it would still be handy to know the year/model/trans when diagnosing driveline probs.

If you can get the car up in the air safely, you can look through the grating under the torque converter and see if it turns with the engine. If the engine runs and the torque converter is not turning or is turning slower, you've immediately identified the problem as a torque tube or driveshaft coupling failure. If there is still a bunch of noise, you can probably figure out where it's coming from, again narrowing down the possibilities.

groppo

Cars laid up for now - I want to forget about it for now. I plan to have a look from underneath in the later this week. The cars an auto, 1990 S4.

groppo
1990 S4 Auto

Bill Ball

Bob mentioned looking at the torque converter with the car running. Even simpler, if you can turn the torque converter with the car stopped, the torque tube shaft is toast. This is the third one reported in as many months. Look at these threads about one with which I am familiar...
https://rennlist.com/forums/928-forum/262975-drive-train-failure-it-s-the-torque-tube-photos-posted.html
https://rennlist.com/forums/928-forum/264113-toque-tube-replacement-date-is-4-8-for-edco-s-91-s4-update-tt-removed-photos-added.html

edco

Hey groppo,

That sounds similar to what happened to my 91 S4, the car Bill linked too. I'll hold out for it being the bolts on a half shaft but worst case scenario we have done a TT without pulling the tranny

groppo

Heard from the mechanic. With the car up on a hoist he could turn the torque tube with his hand. So I guess all roads lead to either it being a snapped torque tube or bolts on half shaft.

Peter Gropp (groppo)
1990 S4 auto

Nicole

This is an interesting statement. You can't really turn the tube - only the drive shaft inside (which is not the same as the half shafts / axles that connect the differential to the wheels).

If you can turn that shaft inside the torque tube by hand, it indicates that it has no connection to the crankshaft. This means, either the shaft or the flex plate is broken.

Jim bailey - 928 International

I have rebuilt tubes available. Just call me

k1woods

could also be a broken rear flexplate, easy to check as well.

- k1woods 82 S2

groppo

Had a look at car today - torque tube has gone, same problem as posted at
http://forums.rennlist.com/rennforu...ad.php?t=262975

Now I'll figure out the best place to get one - here is Australia or US. I've bought parts before O?S and shipping costs have been okay but this may be a different story. I'll contact Jim at 928 International. Porsche Aust have none.

Peter Gropp

Bill Ball

Just for others...the link is:

https://rennlist.com/forums/showthread.php?t=262975

The Rennlist forum software abbreviates the URL in the display, so if you copy one from another message, it won't link properly. You have to use the old link to navigate to that page and copy the URL address from the target page in the browser address bar.