Access to the differential

Well, if you have a car lift, Saab does have a tool for suspending the engine in the car while dropping the tranny out the bottom, but it's not a home-shop thing usually.

I don't know, but I'm curious what about the differential needs help? Is this a pinion bearing noise problem, or something else?

Dave Hinz

No, you can't actually work on the diff with the tranny in the car.

Removing the engine of a c900 isn't that bad a job, and once you've uncoupled both driveshafts you're half way there anyway.

Think of all the other stuff you can easily do with the engine out - clutch, crank seals, cv boots, engine mounts, coolant flush, oh I could go on... Obviously only worth doing if you intend to keep the car a while.

If you're going to pull the engine/tranny, don't forget to push in the clutch and insert a spacer ring *before* disconnecting the hydraulics.

And, when the end does come, there's a real chance that you may wreck parts when it comes unglued...right now, you just need bearings & labor. Later, who knows what will get munched when chunks of bearing are rattling around inside the case.

...or, a couple of miles. Depends, I suppose, on how much of a problem it is to get stuck. If you're going to keep the car for any length of time, I'd say fix it now while you just need the cheap parts. If it goes kaflooey on you, it could be more expensive to fix than the car is then worth.

Dave Hinz

Totally agree. I had a friend with an '81 900 where the pinion was well and truly gone. It was very loud indeed. He drove the car like that for 25k miles, before one day it failed catastrophically. He knew it was coming - it was kind of a game for him.

Thanks for all the info/advice. I think I'll drive it for now, ( the noise just started, and is very subtle) and take my chances. But I will be well aware of what is to come ......

--Pakob