1986951

Any thoughts on why a 2nd gear downshift is sometimes stiff on an '83 SC with <60K miles? Otherwise the trans is smooth and tight; no growls or graunches...
Clutch is relatively new (8K miles). All other gears shift fine, and no problem on an upshift. I have noticed that if I move the shifter toward 1st just a bit, then 2nd engages much easier on a downshift...

Would a switch to a different trans oil help? Redline / Swepco, etc.???

SeattlePorsche

Shifter bushings I would say. Wow, that is a really low miles SC!

redtdi96

I have same problem with my 80 SC ~60 k miles (aka garage queenie).

I have tranny out replaced all synchros-1/2-3/4 sliders, and 2cd dogteeth (two teeth were broken).

The tranny looked like 60 K miles. Now I will report back after it is in a running, big step between here and running. taking a tranny apart > putting gether and finally running is a major step.

1986951

Yes, a very low mile "Sweetie"... IIRC, the Shifter Bushings were replaced at about 55K... will check my records to be sure... I look forward to hearing how the rebuilt unit works out for you!

Mine is nowhere near needing a rebuild, but prolly could use a fluid change, so I will try that first. I seem to recall that the 915 tranny in my 75 Silver Anniversary was sort of "stiff" in 2nd gear up and down, now that I think about it... could be just an issue with the 915's???

SeattlePorsche

Nope, I don't think it is inherent to 915's. My rebuilt 1st and 2nd are very smooth now. 3rd and 4th are still breaking in so sometimes they are a little stiff. I doubt that your 2nd is stiff because it isn't broken in yet. Changing the fluid is a great idea!

Actually, what do you mean exactly by stiff. You mean it is hard to engage it, or it grinds? My 3rd and 4th description refers to engagement. If you mean it grinds, you might have some broken dogteeth. When the syncro rings and sliders are brand new, there is a friction fit there and the slider will feel resistance as you try to push it over the syncro ring. That spins up the tranny and then you push a little further and finally engage with the dogteeth.

But I hope that is not your problem.

1986951

Nope, no "grinding" whatsoever...more like what you are describing as resistance pushing over the synchro ring, and then it engages... "Stiff", as in it just doesn't want to slide in easily... BUT... it does help if I just ease it toward 1st and then back into 2nd... goes in smoothly every time... maybe symptomatic of some issue...

SeattlePorsche

Oh, that's good. Maybe new swepco in there will fix it.

theiceman

what about the coipler adjustment, we are just talking about that on another thread.

UberXY

My '85 was the same way - there was no speed shifting into 2nd, that's for sure. But my '84 Targa (39k original miles) shifts as smooth as butter in all gears.

Steve
84 Carrera
00 M5
02 G500

Mike Murphy

I think the reason is that 2nd gear gets the most abuse of any gear. It's the one gear that will always get used in driving, and it's the one gear that gets used when sprinting a 0-60 test. My guess is that you, like most other stick shift owners, have more wear on 2 than on the other gears.

911pcars

Double clutch to reduce further synchro wear. If you do it right, it reduces upsetting the chassis during downshifts.

Sherwood

911SC SKI

I have the same problem with my 83SC. Have it in the shop at the moment as the synchro into first is gone as well. You can get it with a double de-clutch, but, as said above, 2nd just doesn't seem to line up.
Wondered if it was possible or worthwhile upgrading to a G50? Anyone tried this or no what's involved?

Ski

wdonovan

I definitely vote syncro. They clue is that when you use the first gear syncro to help speed the countershaft, it shifts more smoothly. Try double clutching. If it helps, thats a further indication of a worn syncro.

dsmyth

My 85 911 does the same with 53000 miles on it. The other gears are good its only 3-2 shifts. Since my oil change to Sweptco its now easier but goes in only about one third of the time. No grinding sounds and a big hard tug will put it in if necessary. A throttle blip helps sometime. Doug