Possible Transmission Issue

[andrew1984wagon]

HELP!

On my way to work this morning my 1984 Wagon wouldn't shift into 4th. Usually I hover around halfway to a little more with my temp gauge but my baby was heating up as it was working harder than it should have in 3rd gear. There were no grinding noises and I intend to smell the transmission fluid when I get back home, but I thought I would check here before I get home.

It's automatic and I just had the water outlet (coolant filler neck) replaced. My radiator needs a good re-core but idk if this has any bearing on that. I did have some electrical stuff on my dash fixed recently as well and it was just smogged within the last couple months. The timing was adjusted to pass smog. I'm just listing everything that has been done recently so someone way smarter than me can possibly give me some insight. If it's the end of my baby (aka Marilyn Vanson aka Vincent Van-Go aka Vanny Ramirez), then it is what it is but I wasn't sure if anyone knew what it could possibly be.

Thanks

[Burntboot]

A rad that needs work certainly isn't going to help the situation.
That said, you van actually has a 3 speed transmission, 4th is an overdrive.

Try searching the data base for "overdrive not engaging"