Anthony Nuzzo, the owner of Accord Transmission & Differential, originally gave us a call on a 2003 Saab 9-3 2.0L Turbo, using the AW50-40LE transmission that was experiencing a harsh engagement into reverse when hot. His tech Pete Morreale was out on vacation so Anthony was handling the diagnostics, making him quite a busy man.
How often do you get to say this as a technician: “I have never seen this before”?
Such a day occurred for me recently when my customer had his 1991 Saab 9000 towed to our shop with a no-start complaint. Little did I know what I was in for! Spoiler alert: Do not look at the last two pictures yet; try to figure this one out first.
Let’s start with identifying the AW 55-50 valve body and the differences that matter when you’re choosing a replacement valve body. There are four castings, which can be identified by either a letter cast into the valve body just to the right of the S4 solenoid or a blank spot.
The 604 was the first American computer-controlled transmission with adaptive shift strategy. The relearn process was not much different from what it is for today’s transmissions. For those of you who were not in the transmission industry back then, there was no quick-learn procedure for the 604. The quick-learn feature was not available until the mid-’90s. You actually had to drive the car at different throttle openings to relearn the shift adapts, and it could take 30 minutes or more of driving time to get it right.
The past winter months brought to surface a condition of no upshift from first gear when cold with the SAAB/Volvo 50-42LE transmission. When it warms up, all shift sequences are restored. The time in which this occurs varies.