Feppas

Hey all,

So I've been slowly doing work to get the 944 in proper working condition, about to replace the rotors and rebuilt rear calipers. When I had the car up on the jack I decided to turn it over and give a listen to the transmission. This video was the transmission in 5th gear. The driverside CVs and halfshaft was replaced and I was about to do the right side until I heard this sound.

What do you guys think? Should I start looking for a replacement? The fluid was 100% topped off, checked it right afterwards. This is quite a sound.

When in first thru third I didn't quite hear it nearly as much as 4th and 5th. not sure if that was due to tire speed or that the 4th and 5th gear bearings are shot?

Without further ado, here's the heartwrenching video:
http://www.youtube.com/watch?v=0g71oT0y4qc

Thank you all for your input!

-Reed

83944

My bet - CV joints.

I would also be careful running the car in gear with the CV joints fully extended as in the vid...

Try http://www.clarks-garage.com/

Just my 2c worth - good luck.

Feppas

You think that the other CV is making that sound? I distinctively thought that the sound was coming directly from the transmission. The driver side is brand new, I'll replace the passenger side as well. Thanks for the tip on having the CV's fully extended. I'll try to jack up from different points next time.

kingston944

Yea sounds like from transmission to me but I would disconnect the cv's from trans and do it again then you should know for sure .

83944

It is hard to tell fron the video which sound relates to what part of the transaxle.

I am no mechanic but because the transmission is running with little or no load any lash from within the transaxle might be causing that noise. You might be able to feel any lash by hand with engine off and transaxle in-gear. Try to rotate/rock a wheel - employ an assistant (a pert blonde in tight shorts is the go) to hold the opposite wheel. There are detailed tolerances published somewhere for the transaxle. Just a matter knowing where to look.

There may be a magnetic oil drain bung on the underside of the transaxle, drain the oil and check that bung for any "extra bits" that might be attached. That might give you a clue to the inner workings.

Just offering a few suggestions. Do the simple things first. I know that removing the transaxle/torque tube is a big job only just to find that the transaxle is OK.

Given the time/effort involved - best to replace the clutch while you are there! I do enjoy spending other people's money.

Can you hear these sounds while driving?

Cheers
Andrew
Good Luck agian.

Feppas

good advice. I'll replace the passenger side CVs, drop both ends from the transmission and try again.


the clutch was done last summer with a friend. So that makes me think the trans will come out much easier this time around...

Feppas

Well, I just hear an absurd amount of noise coming from the rear end. Furthermore I hear a clopping sound at slow speeds.

Just a note, I can rotate one tire multiple degrees (est. 7-10 deg) while the other is planted. It feels way too loose. Internally I can hear a really audible click from the rear of the transmission. It just doesn't feel correct at all.

DHC6

diff maybe?

Stephencs601

If you need a trans, I have two extra sitting in my garage. One from a 87 NA, the other from a 86 951 no oil cooler.

Oddjob

The 944 series transmissions make a lot of noise when running unloaded. When the bearings are not loaded the pinion shaft is floating. Rattle noise is common. Hard to tell from the video if that noise is excessive or normal.

I have put in fully rebuilt transmissions and they sound like there is marbles rolling around inside the case.

Was it making any excessive noise when last driven?

Feppas

Interesting, Oddjob. There's a lot of rattling/vibration from the rear end, as well as a good amount of clopping (best way I can describe it is a horse following my car). I'm putting in new rotors and changing out the passenger side CVs for new ones. I'll report back with my findings.

That definitely comforts me a lot though. When I heard that sound a few days ago i was terrified. I really hope the clop sound is the passenger side CVs going bad.

Whats a good way of seeing of my wheelbearings are shot? Rock the tire in and out?

Oddjob

Whl bearings typically make a grinding noise when loaded during turning.

CV joints will make a thumping or ticking noise, rythmic with a frequency based on the vehicle speed.

Pinion bearings will make a progressively louder whirring noise that will come from the trans, and will sound different depending on if the trans is under load or unloaded.

What is the mileage on the trans? Did the noise start all of a sudden, or is it something that was subtle and has gotten progressively worse over time.

Has the fluid been drained, and refilled, or just topped off? Any metal flake or bits in the drained fluid?

Feppas

I really think the whirring I hear and the clopping i hear are totally separate-- the clop is CV (which I'm replacing friday) and the whirr is trans.

Mileage on trans is 140K. The noise (i think) has gotten progressively worse. If I have time Friday I'm going to drain the fluid and look for metal bits in the fluid. I made sure it was topped off last Sunday, now I'm going to drain it 100% and refill it.

As far as wheel bearings go-- I hear no difference between turning and otherwise. I hope these can be ruled out. I'm going to try rocking the tire in and out (towards and away from the body) to see what kind of slack there is.

Any other diagnostics to do while I'm under it on Friday? Rotors come in next week and those will also take care of some potential whirring I'm hearing, mine are warping.

tifosiman

Right now that's the best thing you can do. Its not difficult to do and probably needed to be changed anyway (if the trans is good). When you drain it, if the R&P blew up (which is the normal mode of failure for the N/A trans) you will know it. There will be all sorts of little shiny metal bits from sheared teeth.

Feppas

Wouldn't it not run if the R&P blew up? I've been driving the car plenty. Lots of vibration and noise going on in the rear from whirring to clopping sounds. Very exciting. Rotors, CV joints going in tomorrow and I'll swap my fluid.