924Board.org

[Beartooth]

I emailed both EBS and CMS; I didn't hear anything from EBS, but CMS got back to me promptly and seemed pretty helpful. Their response:

"Hi William, thank you for contacting us. Low gear grinds are common and synchros and synchro teeth are available. But 1st/reverse shift sleeve not which certainly ups the difficulty level if needed – and its very likely. Estimate attached for what we can provide. LMK what else is needed after you open and inspect the gearbox."

So I probably have a major missing puzzle piece in the 1st gear shift sleeve; hopefully I don't get stuck digging for the best used one I can find... It looks like I'd be at $1800 for the parts they have - that's including the 2nd/3rd wear items (syncros, shift sleeve, and dog rings). I think I understand the dog rings - those are splined to the gear with teeth on the outer end, and together with the syncro and shift sleeve form the engagement mechanism, correct? It's just that on other transmissions I've messed with, those are either integral or maybe pressed onto the gear.

The good news is, I drove it recently, and I couldn't make 3rd-5th misbehave, so I may not need much outside of first and second gear. And of course that's the hard part (1st gear anyway); pretty frustrating that Porsche couldn't address those NLA parts. I'm going to make an effort though - even if it means throwing a bunch of money at having it repaired (assuming that's even an option). Although it's driveable, it really is a drag to work around in stop-and-go. At least there doesn't seem to be too much more to address; I'll just have to see, but I might get away with just a synchro on 2nd. With care, I can always get 2nd without a problem, but I really have to be careful with the upshift.

Anyway, I hope I'm not thread-jacking too much here! It definitely seems like CMS will be good to work with. It's too bad about the 1st/reverse shift sleeve; I'm guessing the precious few NOS sleeves on someone's shelf either aren't likely to come out, or they'd cost more than the price for a decent used box (not that those are easy to find!).
_________________
1980 931 diamond in the rough

[chuck21401]

[Beartooth]

That's good news; it jibes with a follow-up email from CMS that mentioned a reproduction may be in the works. No thread-jack at all because it seems the first gear parts are the most needed and the most lacking components for the G31. Based on other posts, I'm betting hundreds of rebuildable G31s have been scrapped because first gear got trashed and the parts couldn't be found, probably at any cost. I'm sure the price will hurt (the 2nd/3rd sleeve was quoted at $467; I'd think a small run of 1st/rev sleeves would be significantly more), but it'll be great if we have the option. The good news is, I might be able to slip in under $1000 for the other parts I need, but of course that's just an optimistic guess until I get it apart. So here's hoping that materializes and we're able to fully repair our 'boxes. I can only imagine how much a solid gearbox and shift linkage will transform my driving experience!
_________________
1980 931 diamond in the rough

[Cedric]

[kevingross]