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-   -   3 to 2 downshift problem (https://rennlist.com/forums/996-turbo-forum/419045-3-to-2-downshift-problem.html)

rwilliamtaylor 03-24-2008 02:23 PM

3 to 2 downshift problem
 
A couple of time over the last month when I downshift from 3 to 2 I get a grinding noise as though the clutch was not depressed. The rest of the time it shifts with no problem and I always heel - toe and have never had a problem with bad shifts. This is not the second gear pop out problem as it passes that test with no pop out. Today, after the first bad shift, I tried very deliberately pressing the clutch and shifting to second and got the same grinding for the next two 3-2 shifts. The problem then went away and it was back to shifting normally.

This is the third time in a month that this has happened. I've also noticed that my shifter feels a bit sloppy and has a clunking noise as well. Could this be a shifter problem?

I ordered a B&M short shifter from the guys at Bumper Plugs yesterday to see if a new shifter cures it (and I wanted one).

Shifter is stock.

I ordered a B&M short shifter from the guys at Bumper Plugs yesterday to see if a new shifter cures it (and I wanted one).

Any ideas?

Rickard 993 Turbo 03-24-2008 02:58 PM

syncros

Barney1 03-24-2008 06:28 PM

Syncros.....A common problem with the 993 and the 996

rwilliamtaylor 03-24-2008 07:08 PM

What's involved inthe repair?

Can the synchros be replaced or is it a total rebuild?

Mine is an X50.

Barney1 03-24-2008 08:28 PM

The motor and Tranny has to come out. You can just do the syncros, But the job was in the area of $4,000.00 parts and labor. Oh and while your there might want to do the clutch another $2,500.00
Sorry for the bad news. If you get it done soon you most likley will not need a second gear shaft assy. That alone is $2,500.00.

k4site 03-28-2008 02:28 PM

Double clutch

Land Jet 03-28-2008 07:56 PM

I would have the shift cables checked and adjusted if needed, before considering the engine drop and tranny rebuild.

1AS 03-28-2008 11:53 PM

Sounds expensive. I think I'd give up the heel-toe or double clutch techniques on the street. it isn't necessary, and seems to be backfiring on you.
I think if I were rebuilding the box, I'd regear first and second to make them longer. Personally, I'd like first to get to 50 mph, or close to that. AS

Bob M 03-30-2008 01:03 PM

Same thing happened to me -- synchros went bad. I'd get it fixed soon as any metal particles and broken bits moving around in your tranny will damage gears and parts as well. The suggestions to change clutch and gearing are good. I added a lightweight flywheel and an upgraded clutch when I did mine. In retrospect, I should have changed the gearing too. If I had to do it over, I'd also ask the mechanic to use the steel synchros out of the GT2/3. The bronze synchros used in the TT are a little too delicate, in my opinion.

rwilliamtaylor 03-30-2008 08:13 PM

Thanks for all the replies... I may have got lucky though.

I installed a B&M short shifter and while taking the factory shifter out I noticed some broken pieces of plastic under the shift assembly and lots of "end play" in the shifter.

I've driven about a week now with no incidence of the bad downshift.

I love the feel of the B&M short shift compared to the sloppy factory unit.

I'm going to get an oil change and transmission fluid change next week.I'll get the mechanic to check the fluid that comes out for any material just in case.

BTW, Since I have the X50 option, I thought I already had the stronger syncros??

1999Porsche911 03-30-2008 09:06 PM

Sounds like syncro is bad. All it takes in 1 bad shift and you can destroy a syncro. Steel or otherwise. Test it like this: Drive in 3rd, depress clutch pedal, shift out of 3rd, touch 1st and then go into 2nd. If there is no grinding when there otherwise would be, chances are its the synco.


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