Drove my '66 earlier and realized something odd: my auto-tranny wasn't shifting. It stuck in first gear until I hit about 20-25, and then wouldn't leave the next gear until I passed 40. It seems to suddenly have a very set shift point?

 

Change the vacuum modulator

 

Thanks, man. Where's that located on the tranny, btw?

 

It is on the right rear corner of the main case. It screws in but you need a very thin wrench to tighten it properly. It may just be the hose fell off too.

 

Ah-haaaah. I found the culprit. When I had the engine rebuilt, they put a larger nozzle for the vacuum hose than the actual hose that was used. They glued a larger piece of hose to the smaller hose so that it would fit the new fitting.

I had to take it off the other day to set the idle and the glue broke, so I put on this adapter that fit the hose perfectly. I guess it was some kind of plastic, though. It melted. It was sitting right on the temperature hose from the carb.

Thanks for the help! Greatly appreciated. Now I can get that fixed.