Bradman69

I have a 1969 cutlass S with a 350 rocket and a jetaway trans, I notices some transmission fluid dripping a a pretty slow rate when ever i have it parked different places for a period of time. I figured by now its got to be getting pretty low. It has sat all winter and today was the first warm day we have had all year. I drove it to the gas station and on my way there i never heard or felt my transmission shift. I was going about 55-60 at around 3,000 rpm. I tried to make the car shift but it wouldn't Does anyone know around what mile per hour It should be shifting into second. I checked the fluid and it read full. What should i do to make it shift (i have a column shifter)

droldsmorland

Was the fluid pink and did it smell ok? When was the last time the fluid and filter were serviced? It's likely time. Do a full trans flush and filter change don't just drop the pan contents. There are several more quarts in it(8-10 total).

You need to somewhat clean the trans(wipe it down) and determine what area the leak is originating from. Many things can cause a leak. No way to diagnose online without specifics or visuals.

Here are some of the reasons for the lack of a 1-2 upshift in a 2-speed Jetaway.
1. a vacuum leak in the line which is routed from the intake manifold on the engine down to the modulator control valve on the side of the trans. Check that line. It may have a steel line with a rubber line on either end. Make sure the steel line isn't restricted. Replace the rubber lines.
2. The modulator could be bad. It can be tested. No fluid should come out when you pull the vacuum line off of it.
3. The governor could be sticking or damaged. Pull it, inspect, repair or clean it.
4. Shift linkage is out of adjustment. Can you feel and hear the detent clicking each time a gear selection is made? You should hear a distinct click for R N D S.

There are deeper internal problems that will cause the lack of the 1-2 upshift. The above troubleshooting checks are the basics. If the above remedies do not cure the problem then the line pressures need to be observed. Line pressure readings will diagnose internal cross leaks or blockages or a worn out transmission etc...

I have the line pressure charts if needed.

oldcutlass

The modulator valve needs to be connected to manifold vacuum. Did you check your fluid level with the engine warmed, running, in park or neutral?