longrunner1

Ok, guys need some input, just purchased a 1991 S2, bought from a fellow West Coast PCA MEMBER, he gave me full documentation, service records from first owner right thru till his owner ship, talked with his mechanic and the previous owners mechanic. He did a full service water pump, belts , cam tensioner, pads etc. , he offered for me to get a PPI,but after speaking with his mechanic and the previous owners mechanic, I the trusting guy that I am waived that. The car came delivered and as far as the exterior and interior, rims etc, it was truly in concourse condition, best I and my fellow Pca members have ever seen. Now comes the good part, brought it in to our well respected first choice Porsche technician, for an inspection sticker , and post purchase inspection. Upon his inspection , he found rear crankshaft seal leaking, and steering rack leak which I knew about and was mentioned by seller, told him lets rip it apart and get it right, mentioned to him the shutter down shifting from 3rd to 2nd, always there regardless if you are coming down at low rpms , worse on high rpms, Clutch was replaced 30k ago, upon opening everything up, clutch was fine and flywheel was perfect. Everything put back together and car runs great and cool water temp, great smooth shifting in every gear and down shifting, except have to be careful to come down at low rpms from 3rd to 2nd. Our mechanic really had a full workload, and he told me to bring it back at a later date to follow thru. Any input guys? regardless of this problem I still would have purchased the vehicle, figured I would have to sort some mechanics out when I received it, but wouldnt it be nice if everyone would just be forthcoming and honest and a straight shooter!

MacinTek

Whew! I'm glad I'm not the only '91 S2 with this issue... All the same stats as your description only my clutch was replaced with a Cetnerforce Dual Friction. 'Glad that wasn't it. Anyway, I don't know the answer, I'm just responding so I'll be in the loop of responses from those who my might.

eohrnberger

I remember that. Seems to have gone away with the replacement of the rubber spring plate bushings, oddly enough. Got Poly Graphite in there now.

longrunner1

Thanks guys, any input is greatly appreciated, forgot about the shudder the other day and did not baby her going into 2nd from 3rd, thought the tranny was going to drop out of her!

azbanks

Mine does that too.

Squatting Ninja

Put me on the list with this same problem with my '90 S2.

For aggressive driving where downshifting is needed from 3rd to 2nd some rev matching w/heel and toe stops the vibration completely once you get the knack of it but it would be nice to work out what the actual cause of this problem is.

I wouldnt think it would be the spring plate bushes since it only happens from 3rd to 2nd and is more violent at different RPM's.

IIRC the previous gearbox I had on the car did the same thing until the R&P got destroyed. Im unsure where to start, ill keep this thread updated if I find any solution

1933beer

Ok guys I have the issue with my car and this is what I can tell you. I replaced the fluid in the transaxle (it was old did not have records of change) I used redline because I could source it locally. It made shifting better for all gears. It also improved the down shift into 2nd gear although not a complete fix. So why did I do this? In asking around here and on 944 online.I found it is a worn sincro in the transaxle. the only real way to fix it is have it replaced. Ian at 944 will refresh your transaxle if you send it to him it was about $800 plus shipping when I looked into it a few years ago. I plan to do it when I need to replace my clutch but for now she works well as is. I hope this helps.

beer

Mueller944s2

I had a shutter once, thought the tranny was gonna fall out (mainly starting from a stop). The pressure plate bolts were backing out because we hadn't replaced them on the engine swap and it was no longer even with the clutch. We tightened that whole side that was coming loose and after maybe a week or two the shutter was gone. I guess it had to wear itself evenly again....of course then a few months later the center broke out and I pulled the clutch out in two pieces.

eohrnberger

Seems like there are wide variety of potential issues and solutions to check with a 'stutter downshift' or 'shudder downshift' symptom.

I too have swapped old gear oil for new. But it was the spring plate bushings which seemed to have cleared mine up.

If you are worried about syncros on downshift, have some fun, develop some skills, double clutch on the downshift.

Yes, it is true that you really don't have to with these transmissions, as they have synchros, but you can reduce / eliminate stress and wear on them by double clutching, and bonus, it sounds cool, and double bonus, the car will be less unsettled as you go through the braking zone into the corner turn in point.

Now, for added bonus points, be able to double clutch while heel-toeing and at threshold braking. I'm still working on that one.

944hal

Interesting. I have the same problem with an '89 S2. I just replaces the clutch, pressure plate and refinished the flywheel. It didn't shudder with the old rubber center disc but it does with the new one. It also chatters some in 1st on start up. Replaced the real seal also, so there is no oil involved. Nothing wrong with the trans either, other that it's out of a 951. Getting the S2 trans fixed.

eohrnberger

Very similar to my experiences.

When I put a new clutch in, it was the whole thing, new flywheel bolts, throw out bearing, the little sheet metal thing, etc. etc. Motor mounts have been replaced as well.

Like I said, the shudder was there all the up until I swapped the poly-graphite spring plate and delrin banana arm bushing in, and then it was gone.

Other posters have said that I'm nuts, but somewhere along the line, something soft and worn was replaced, but I can't put my finger on what exactly.

Mueller944s2

check the clutch fork if you're pulling it apart. The tip of the arms get worn on the inside edges.

eohrnberger

Just went through a rear main seal replacement. No issues there. But then, I don't have that issue anymore either.

Edrtith

forgot about the shudder the other day and did not baby her going into 2nd from 3rd, thought the tranny was going to drop out of her!

dmcampbell

Worn cv joints. I had same problem (3-2nd DS/take off in 1st) on my Turbo S after installing Spec Stage 2+ clutch and aluminum flywheel. Lived with it for a year and then replaced axles with the cheap EMPI's and all shutter is gone. Mike