Okay I have a 1994 Toyota 4 runner 3vze Automatic 4wd that I have been trying to get it to shift into overdrive on the interstate. I recently changed all of the solenoids and then drove it 200 miles round trip and it shifted great. A week or so after the trip It started not shifting into overdrive. Now when I bought this truck I have never seen and OD light come on. You could press the OD button and nothing would happen. I went to a junk yard and bought a replace shift knob and spliced the two wires together for the button. Now all of that was done prior to changing the solenoids.

So after it started not shifting again (and when I say not shifting I mean at 60 mph I am at 4000 rpm's on the interstate and cannot go any faster) I decided to look at the spliced wires. I took them apart,stripped them and this time I soldered them together. Okay for the first time in 16 years I can push the OD button and see the light! Took it for a drive shifting great. Drove a few more miles maybe 4 miles doing 70 mph and then all of a sudden it downshifts and the rpm's are at 4k .

So does anyone have any ideas on how I can fix this? I love driving it and this is keeping me from doing so.

Thanks

 

When the "O/D off" light is on, the transmission should not shift into overdrive. So if you have problems with the O/D off switch and light, you want to make sure that's taken care of. For instance, if your switch is stuck closed (closed is O/D off), or you have a bad wiring job, AND the bulb is burned out, of course it won't shift to O/D.

The transmission will not shift to O/D, no matter the switch position, until the ECT is "warmed up." If your ECT sensor is not working, it won't shift (though a non-functional ECT sensor should cause a lot of other problems as well).

Here's the manual page for the A340H. http://web.archive.org/web/201408160...34electron.pdf I think that is the most likely transmission you have, but it's listed on your door pillar.