42RH 2WD. I had trouble with the thing not shifting 2 to 3 unless I let off the gas. That is no longer the case ahven't had any issues with that in a while. Now when I am driving down the high at about 65 to 70 after a awhile (probably 10 to 15 miles) the thing shifts out of overdrive and will not go back in. It stays in 3rd. But if I let it set overinght its fine the next day. It doesn't happen as long as I don't drive to far. Because I never have an issue driving to work about 7 miles.

Overdrive solenoid maybe.

 

Are you getting a Check Engine Light? Tons of possibilities from is a bad speed sensor or bad wires. Or like you said a bad OD solenoid or a bad switch.

 

Your right about many possibilities. I don't know how many posts I've read on this. No tried 4 or 5 times checking for codes. Just got 55 over and over. Called a transmission shop. Can't recall what he said. Something in the front section seals were going bad. He said dump some TransX in it and give it two weeks.

 

Your truck may be similar to my Dakota where bad crank sensors are the problem. Before my engine swap last month my tranny sometimes stuck in neutral before shifting to the next gear or stuck in one gear too long and revved really high before switching to the next gear. during the engine swap that mechanic put in new crank sensors (about $120 for both sensors) which fixed the problem. I realize the symptoms are different from yours but the crank sensors could also be your problem though the symptoms are different.

Let us know what you find out and when you get it fixed?

 

Well it seems the 2 to 3 shifting issues has been solved, but no improvement on the shifting out of OD after I've driven down the highway about 10-15 miles. That's what stumps me. Its fine if I drive 55mph to work, about a 5 mile trip. Could it be something electrical. Heating up and faulting then cooling back down and works fine. I changed the trans fluid, but I've been using Orielly's Brand ATF4. Now that I think about the truck was fine when I first bought it, but started having issues after I changed the fluid the first time. Could it be shotty fluid.

 

It could be the fluid actually. The local parts dealer here had told my neighbor that there is now a special type of transmission fluid specific to chrysler products which is supposed to work excellent for all chrysler transmissions, especially the van's. Maybe you should check it out? Sorry I never got a name of the fluid btw

 

I would run it out for a test and stop right after it kicks out of overdrive, leave it running on level ground and check your tranny dipstick. If the fluid is real hot, I'd drop the parts store fluid, go back to Mopar fluid and make sure the cooler fins are clean and clear. Heat will kill your tranny...been there, done that, bought the T-shirt when my Buick stopped rolling forward up a hill and started rolling back down, backwards. That sux.