After working on the car for well over 2 years, including a rebuild of the TH350 that was fragged when I found it, it finally on the road and has been on short test drives for chassis, steering, and brake checks. I drove it to the exhaust shop this morning, the first long drive the car had been on in 4 years. This car was the owner's husband's car, he passed in 2008, the transmission gave up shortly after that.
Once it was warm the transmission would hang onto the gears, even at moderate throttle input, until I released the gas pedal maybe 1/4". Once up to speed if I pushed the gas pedal even 1/2" it would downshift on me and hold the gear again until I, once again, let off the pedal maybe 1/4" again. Way too sensitive to throttle input, I haven't yet checked how much vacuum the modulator is getting, I also haven't checked the governor springs but I'm hoping for some guidance as I'm not a transmission guru. The transmission did have a shift-kit (of unknown origin) but I didn't make any changes or adjustments to the valve-body other than new gaskets. I did also have to replace the kick-down cable and am wondering if that's too tight.
The engine is running perfect, brakes and chassis feel great, just goofy on the shifting!

 

DING DING DING.

We have a winner.

 

X2, your trans is running around shifted into passing gear.

 

1972 - easy self adjusting cable at the gas pedal, right?

Or you have trans cable to carb?

I thought maybe the vacuum modulator was adjustable and adjusted too far one way. I know you can adjust them to shift hard and late. Kinda fun, good for 2nd gear rubber.

 

The car is at the exhaust shop getting its new Porter Mufflers and stainless steel exhaust so I can't check right now. I'm fairly certain it goes to the pedal, I'm now remembering being under the dash, hooking that thing up and thinking, "I need to adjust this at some point"! LOL

 

And now I remember why I didn't adjust it at the time, it doesn't have the plastic sleeve that clipped into the pedal assembly! Can I unhook it and drive it home?

 

Yes it can be unhooked, you just won't have a passing gear anymore.

 

Unhooked the kick-down from the pedal, left the exhaust shop, drove it home listening to the sweet exhaust note, and other than lack of passing gear the transmission shifted perfectly! I made a collar for the pedal out of delrin when I got home, a whole 10 minutes worth of work, put it on, adjusted it, and it works flawlessly. I'm extremely pleased with the transmission now and the boys burned a half a tank of gas cruising around last night after I got it done. The boys and myself so appreciate the help, guys! This is the first time I've dug deep into an Oldsmobile, you all have continually helped me through all the little details on this car, and I have never been steered wrong. For now, we only have some minor alignment adjustments to do on the front fenders and some other small details but for the most part the car is finally DONE!!
THANK YOU!!!

 

Congrats on the trans. But, it will never be actually done! I keep coming up with a change or two here and there for 3 years now.

 

Oh you can still have a passing gear, it just won't be automatic.

Us your right hand to move the shift lever to S or L wen you feel the need.

voila'... passing gear.

 

LOL, yes or that.