904 Governor Replacement

A&A transmissions (and others, I'm sure) sells governors specific to a max rpm automatic upshift. The actual full throttle upshift rpm can vary from A&A's rating for various reasons, and often the 2-3 full throttle automatic upshift will occur at a lower rpm than the 1-2. Might have to go into the valve body to address that.

A higher speed governor will also raise the part throttle shift points. Nice if you want the car to hold each gear a bit longer at part throttle, especially if you're lacking in low speed torque.

For at least a couple of years in the late sixties, you could not get a Torqueflite trans to shift into low gear above 30 mph no matter how hard you tried - whether just stabbing the throttle or trying to manual shift into low. That was the case with my Dad's (now my) 67 Hemi Charger. Once you were in it, low gear was a 55 mph gear, but if you were in Drive going 31 mph, low gear was just not available. Got smoked a couple of times from a low 30's roll because it would only kickdown into second where the rpm's were maybe somewhere around two grand. No internet then, or any Mopar clubs, or any Mopar-knowledgeable friends, but I did have my car magazines and their ads. I fixed the problem with a B&M manual/automatic kit for the original valve body. Now you could manually shift into low gear at any speed. Note that this is not a governor issue, but a valve body issue.

Anyway, to replace the governor, you have to remove the trans extension housing. The governor is behind the main case, so you don't have to take the trans completely apart, just the extension housing.