I've read the archives on overdrive problems, and I have a simple - kind-of stupid - question. First, my situation:

1993 240 automatic. Bought it 2 years ago. For a while, I drove it on the freeways a lot - no problem. Starting about a year ago, I've been driving almost only around town, never get it going too fast (maybe 40mph sometimes). When I bought the car, I knew that the overdrive solenoid was leaking. I checked the fluid pretty regularly, and it wasn't so bad, so I waited. A couple of weeks ago, I brought it to the dealer to get new front struts, and had them check out the solenoid. They said the solenoid was bad (not just leaking), so I let them replace it. After that, I drove the car on the freeway. It shifts fine through third gear, but at around 40mph it's revving high, wanting to shift into fourth/overdrive, but won't. The overdrive disengage light is NOT on on the dash (it shouldn't be), and the switch on the gear change lever seems to work (makes a click, light comes on the dash). I brought it back to the dealer. They said the solenoid and overdrive are fine, the problem is that the car won't shift into fourth gear. Here's where I am confused. Isn't fourth/overdrive the same thing (assuming overdrive isn't engaged)? I asked the dealer, and he said no - it is separate, and my problem is internal to the transmission. Of course he wants to put in a new transmission! I don't believe it.

I mentioned the fact that I don't drive it fast, because I can't be absolutely certain that it was shifting fine before I brought it to the dealer. But my intuition tells me it was - it doesn't feel right even at 35-40, which I know I usually hit. I don't think it's coincidence that I'm noticing this right after I brought it in for a new solenoid.

So, that's my question: If it's not shifting from third to fourth - whether the overdrive button is engaged or not - is it an "overdrive" problem like the posts deal with (solenoid, relay, etc.), or am I confused? I mean, when overdrive is on, it's not like the car shifts through four gears and THEN overdrive, right?

Thanks for clarifying it for me. Sorry for the long post.

Harry