Classic/Antique Car Repair: hydramatic transmission fluid, automatic transmission fluid, dexron ii

Question
QUESTION: hi,i have a 59 chevrolet apache pickup truck wwhich is fitted with a hydramatic transmission,the repair manual says refill with type a transmission fluid,can you suggest a modern equivelant as i cannot find type a fluid anywhere,thank you.

ANSWER: Hi Ian:
General Motors Dexron-II automatic transmission fluid specification, issued in August 1973, defines physical, chemical, and performance requirements of a new class of fluids developed to meet increasingly severe service in passenger car/truck and commercial automatic transmissions.

You can get this at any Auto Zone and it will perform with less friction than the old Type A stuff. I use this in my Rolls Royce and my Excalibur. But remember, you have a hydramatic. Don't over fill her. As a standard rule, I always fill my transmission to 1 quart low. Then drive it for a good 20 minutes and check it while she is still hot. Only  adding enough to top her off to the FULL mark. If she is cold when you check her and you fill her up cold, she will be over full when she gets hot and that can cause all kinds of problems.

The The Turbo Hydramatic is a forgiving tranny. But the hydramatic isn't as forgiving.

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QUESTION: Hi Vern,Ive took mytruck up the road and the transmissiondoes not upshift.It only upshifts between 1 and 2,there is no 3rd or 4th gear but reverse is ok.With the lever in 1-4,1-3,or 1-2 the result is just the same,the selector rod seems to be working ok.The fluid is brand new,oil filter clean and the level checked as you advised.The truck is a 59 Chev Apache with oem 283 ci engine and hydramatic gearbox,any help would be much appreciated.thank you.

Answer
Hi Ian:
I will need a bit more information. It sounds like she is pulling strong (e.g. gears not slipping). So, when you say 1-4, are you shifting between these gears? Or are you saying the tranny doesn't automatically shift from 1st to 4th gear?

You say there is no 3rd and 4th gear? How are you able to determine that it is stuck in 2nd? Is this because of speed and the tranny is straining?