AGARubberDuck

So most of what I read says the cardan shaft failure results in loud banging in the tunnel. I understand that, but I've also read about shuddering under acceleration being a symptom.

Here's what I have:
Cruising along at 55 - totally fine.
Increase speed mildly to 60 - still fine.
Let off the throttle and there a shudder/rumble for a second or two. It's felt throughout the cabin and definitely in the pedal.

Sometimes this rumble/shudder happens under light acceleration, but almost always after letting off the accelerator. Under spirited driving, there are no symptoms.
I feel this shuddering a LOT during light rush-hour traffic as there is plenty of cruising and slight modifications of speed, speeding up and slowing down without need for a brake.

Ideas?

TomF

Very tough to say based on your description of the symptoms- it could be wheel bearings, differentials or any number of other things... even improperly tightened lug nuts. This doesn't sound like a cardan shaft issue... I would have a knowledgeable Porsche mechanic take it for a drive and see what they think.

I once had really strange symptoms on my 993...intermittent vibration, squeaking, other things... drove me nuts for weeks. I had several Porsche friends drive it, finally gave in an took it to the local Porsche dealer and noone could find anything. I eventually ran into an old mechanic friend of mine who was a an old bug guy... he couldn't figure it out either. After a couple of "I give up" beers, a light went on in his head and we went for another spin around the parking lot. Guess what it was? The center nut on a rear wheel hub had worked a slight bit loose. After re-torquing from 250 to 320Ft/lbs, everything was right with the world.

Nothing substitutes for a test drive with a knowledgable gear-head!

Cheers,
TomF

C4SJOHN

Carden shaft is starting to go, will go out all the way soon. The rubber will rip apart more each time... Get under a take a look....