64 Catalina slim jim

[oldfords]

My 64 always shifts all the way up when you start out. It will shift down just fine as you slow down. Since I know nothing about this tranny, I am looking for ideas.

[Larry]

The Roto Hydra-Matic can be fussy. Very often it is a matter of the shifting rods being out of whack. Adjusted too far one way and it speeds through the gears, too far the other way and it lags through the gears.

Do a Google search for "slim jim transmission upshifts too fast" and you will find a ton of sources that may address just what you need to do. If not just the rods, it could be an internal issue that only a specialist could solve.