Date: Wed, 10 Jul 2002 09:03:18 -0400 From: KeithG <noonenopsamspring.com> Subject: Re: SAAB 900 cracked gearbox casing at oil sump drain
If the plug is overtightened, the case can be pretty easily cracked. Saab did downsize the hex on the plug so that your average guy would not crank it down too tight. Before the 'skid plate' was put on the later cars, it was easy to break off this portion of the transmission case by hitting a curb or such. I have heard of having it welded 'in place' (without removing the transmission from the engine), though have not needed to have this done. Most other vehicles have a drawn steel oil pan with a thick steel insert at the drain. These inserts are also regularly stripped out even though they are steel. The aluminum is much softer and more susceptible to damage. KeithG D J Brown wrote: > Thanks for your comments. I have already "eaten" it - i.e. I've paid > for the repair. However, the information from the metallurgist > suggests that the castings was hardened improperly (something to do > with flow lines within the metal). > > If SAAB knew this (e.g. because this problem occurred frequently) then > I'd be very disappointed - even if not in possession of a case for > liability! > > How common is this cracking problem? I've certainly never heard of it > on any other vehicle. If it's more common than on similar types of > cars, then it's a manufacturing fault or a design fault. I'm > interested to know.