Hello all, I have to let my 77 Maverick warm up for about 7-10 minutes before I put it into drive. It will always go in reverse, but not to drive if I dont let it warm up. Once the car is running and I drive it around this is no longer a problem.....only on the initial start-up.
I have had luck with transmission seal conditioners. If the seals are just dried out, it will plump them back up. If it has gone too far and the seals have cracked, it can be hit and miss. I forgot the name of the one that really works, but my uncle put this certain one in his tranny and it lost the morning sickness literally overnight and never looked back for several years.
What you are experiencing is indeed "morning sickness". The apply piston seals in the forward clutch have become hard and no longer seal until they get warmed up. You can baby it until you are ready to rebuild, rebuild it now, or try using seal conditioner (most of which use alcohol or alcohol in combination with a filler) and the hardened seals will swell and soften. The problem is that all the other seals in your transmission will soften and swell too - including the external seals. They commonly crack shortly after the transmission starts acting "properly" again and then you have leaks. In my opinion - if this is your daily driver you would be best off to get a core from a wrecking yard and go through the transmission yourself (if you are mechanically inclined). You might end up with a transmission that will last another 20 years if you are careful about how you build it. If you don't feel confident in rebuilding your own then you can see what a local rebuilder will charge to build your core. That will leave you with a transmission that you can take your time with and build it the way you want (the one that is in your car now).
