DKillaPorsche

Hey all,

Ive tried searching without too much of a definitely answer.

Ive just started getting some nasty vibration/noise from the transmission area. No noise while under load/accelerating or staying at a constant speed. Vibration kicks in while decelerating while still in gear. The noise does dissipate when revs get low (below approx. 2k rpm). There is also some slight changes in engaging gears - some unusual but minor clunks, etc.

ive parked the car up as i had to fly away for work and i also didnt have a 17mm hex key to check oil level. Aside from this any other ideas??

The tranny mounts all seem to be in good order.

Mike C.

Could be the rubber center clutch going bad.

JimV8

It could be any number of nasty things. Can you tell us a bit about the car. Also was the onset of the vibe sudden.

DKillaPorsche

The vibe came on somewhat sudden. There has been some low level tranny whine but nothing too serious. Then the week before last it got quite bad. It is definitely coming from the rear of the car (i have no rear seats or carpet and the noise is definitely noticeable as coming from the rear).

Like i said from take-off and through acceleration it is all A-okay. But as soon as you pull of the accelerator pedal and decelerate in gear there is some nasty vibration and subsequent noise right down to about 1500-2000rpm. This also happens in all gears.

I must admit that the tranny oil hasnt been looked at for some time. The wheel bearings should be okay as they were replaced late last year. Just wanting to know what else i could look out for...Cheers!

gtroth

OK, "clangs" when decelerating, right?
Does it "clang" a little when you put it into gear or change gears?
Does the drive train kind of feel like it has a lot of play in it?

All signs of rubber center clutch giving up the ghost. Original clutch?

Might also be axles, I suppose.

JimV8

What year, mileage? Hopefully you haven't knocked a chunk of the pinion. If you discovered play on the drivetrain, kind of like it bangs around if your not on the gas it could indeed be the rubber centre clutch thats busted and its banging on the limp home stops.

xsboost90

could be a really bad trans mount, gearbox that needs looked at, a bad torque tube vibrating, a rubber center clutch letting go-usually has a clunk to it.

DKillaPorsche

There is the occasionally clunk/clang when it goes into gear. It kind of feels like a not so nice clutch purely because it feels a bit uncertain while engaging it - or maybe that is just my subconcious. If decelerating while in gear there is a noticeable high frequency vibration (kinda of like driving over a corrugated road) as well as a bbrrrrzzzzz noise. This immediately goes away once the clutch is depressed.

Definitely not a bad trans mount - have checked them.

Its 1983 - not sure on mileage - just ticked back over the 00000 - so without having access to the book i cant remember.

Mike C.

I'll bet your clutch is operating on the limp-home tabs...

951jamie

Look in the clutch inspection hole and see if there is any rubber build up in the bellhousing! If so time for a new clutch! Also remember on the 944 because of the torque tube, sound will travel up and down the tube making noises hard to find sometimes.
jamie@944online.com
www.944online.com

DKillaPorsche

Cheers fellas - much appreciated. I will have a look when i get back home next and hopefully figure out whats the issue. I was told mid last year that the clutch should be replaced but kept going with it - kinda good in the end as i ended up getting another year out of it.

DKillaPorsche

Doesnt appear to be any noticeable rubber buildup and i measured the clutch - as per Haynes -and it comes in at approx. 24mm (service limit being 34mm)

JimV8

The thickness of the material aint the problem Welcome to my nightmare.

87 944 C

how bout a bearing in the trans. it almost sounds the same as what happened to mine in march. came off a highway and there was a slight thunking noise under decel. drove home went to a mechanic the next day and replaced the trans. mechanic told me it's likely a bearing, and if it goes on a highway at 70mph, i could be severly screwed as it can destroy the rest of the tranny. i replaced it with his help for 700 bucks.

gtroth

yeah, you're looking for actual chunks of broken rubber through the inspection hole (not build-up). That would be pieces of the disintegrated 20year old rubber clutch disk. Happens to all of them eventually, usually before the disk wears beyond its limit.