Bq code trans, lost overdrive and shifts late all other gears like pressure is maxed out.


Round Headlights.Like em?
May 25, 2001
Installed a used bq trans from 85 Ttype parts car I had in my 70 gs350 a few years ago. It had sat a few years unused I'm sure, but after installation with new torque converter it shifted perfectly fine just as my grand national does. Car sits most of the time and after a year I realized the shift shaft seal was leaking. Topped it off with fluid to get it going one day and I "think" I put a incorrect quart fluid in when I ran out of dexron to get it to full mark. Taking it out on quick trip around block to move it to other shop it shifted through all gears as normal, then after coming to a stop it seems as if a valve hung up, and now has max line pressure. It holds out on 2nd and 3rd gear shifts till very high rpm, and while I haven't driven it fast enough to tell it seems it won't shift into 4th until over 100mph. I hear a notable pump rattle/noise shortly after engaging gears on startup. I've dropped valve body and could not find anything out of sorts with tv cable or valve. After reinstalling valve body and fixing shift shaft leak, it again shifted through all gears at a "normal" rpm/speed, the first time only,then again reverted to max pressure with high shift points, pump noise at idle, and no overdrive (of course I didn't go fast enough to see, 65 is plenty fast for me). is it a valve in the pump that sticks? Want some good direction before I get it back on the lift. I know it's something simple but don't have time to fool with it over and over. Easier to just put another one in but I k ow this trans is a good one if I can find the issue. Have another trans here for parts too.