OW coded Olds trans are worth something, same as BB and PX and code for Cadillac (don't know that code). As all you Buick guys know All GM trans and converters were built at the Buick trans plant. ALL HD turbo 400 s had what we called (I worked for GM 68-72 in product reliability and engineering) a "HD' or "Cadillac sprag/drum assembly" to handle high torque applications. ALL had steel flat washers (instead of wave type) and 6 plate clutch packs (instead of 5 plates with wave washers). Governor WOT shift points established by each Div. and their application. Big block station wagon 400s also had these features and were sometimes listed in sales info as "HD 400" trans and you could also order a 350 sb and get a 400. All P30 truck and motorhome chassis also had this HD 400 or as we sometime called it a "450". All other info metioned as to how many balls and vavle body apply. Servo spring are different, also as well as valve body pressure. By the by Olds engineering requested from Buick that all coverters that failed the stall rpm spec (stalled higher) should not be scraped if they stalled in two limits, 2300 to 2500 rpm (for BB W30 non-A/C) and 2700 to 2900 rpm (for SB W31). Don't remember BB, but SB W-31 converters had a dark green dab of paint on the rear side (side facing frt pump) or side up in shipping container, to identify for W-31. Thses high stall converters were needed to obsorb cam pluses when at a stop, so as to limit "creep". Alum. rivets are available and you can very easily remove data plate from RH side of trans. soooooooooooo be carefull!
