Almost no parts can be found new, in terms of "hard parts" gears shafts etc. Bearings some are some are proprietary
Stop driving until you determine what has failed. Assume you are going to have to buy a good used..
Thanks for the info! Is the G/GM number visible with the transmission in the car? I seem to either be blind or not looking hard enough.That SUCKS.
There are sort of four generations of c900 transmission, and most parts swap within a generation. Compare the G/GM numbers on the primary housing.
@mylesc can rebuild one for you for a very reasonable cost.
Yes, I was horrified when I first discovered all the damage.Dropped from what? a 747 flying at altitude? That looks bad.
yes, it is on the top of the primary chain case, On a turbo you may have to move, look under one of the pipes for the turbo/intercooler.Thanks for the info! Is the G/GM number visible with the transmission in the car? I seem to either be blind or not looking hard enough.
Yes, that sounds like the symptom and progression, thank you.Pinion bearings make a 'singing' noise; one unchanging note.You'll first hear the noise in 5th gear: ON with any throttle, OFF when you let off the gas or shift to 4th. As it gets worse, it will do the same in 4th, 3rd....
Other whines, clicks, and whirs are probably not pinion bearings. Boost won't break the transmission, it's usually the sudden engagement of the clutch or the sudden stop of the pinion when bearings shatter.
Understood, thank you. The full numbers are: GM 457 12 and GM 556 02.There should be more numbers, should be something like GM45606 and GM 55610 or something.
Changes between the 45 and 55 series, depending on the whole number. external vs internal centering, shift fork size pinion bearing and ring/pinion ratio. We need to know the complete trans model number.
Even with that you can't be 100% sure it is what the tag says after all these years.
Thanks for the info! I think the 3.89 box is my preference moving forward, so finding a good case would be nice.I think you're thinking of the twinsaabs site, which sadly seems to be no more.
Oh, but there is also 900aero - forgot about that!
In any case, both are externally centering, but one is an earlier small pinion bearing 3.67 final drive and the other a later big pinion bearing 3.89 final drive box. I don't think there is anything useful compatible between the two. If the 3.89 box is just broken, maybe you can find good case?
It's a real pretty car. I would personally give the $1700 to Chris and get a rebuilt gearbox. Maybe he'd want the other two for cores which might offset the pain a bit.
It's funny, because back in the '80s $2k or $3k for an Ericksson box seemed like an insane amount of money when $1k would buy a manual gearbox for most cars. These days, Chris's $1700 is pretty competitive compared to what you'd pay for a manual transmission. You'll pay $1500+ for a used F40!