I've got just a slight problem. Whenever I switch on my overdrive button, it will just kick in and out when i'm driving along.

I'll be going down the highway with overdrive on, then all of a sudden, it'll just kick out of overdrive, and my rpm's will jump up as if i were still in "4th gear." It'll then suddenly kick back into overdrive and drop back to the normal, lower, "5th gear" rpm's. It'll just keep kicking in and out of overdrive until i turn off the button completely. The interesting thing is, whenever it kicks in and out of overdrive, the actual overdrive light on the dash remains lit the entire time.

Does anyone know what might be goin on with my car? Might it just be a loose wire somewhere, or could it be something more serious?

I'd appreciate any info/help........thanks.

Robert I

Thanks for your help everyone.... it was the tranny fluid that was low, but if for some reason my overdrive acts up again in the near future, i will keep in mind the other problems that you all mentioned that might be associated with the kicking in/out...

Robert

I had this happen to 2 240s (1983 and 1984) at about 180k. Turns out the seal(s) in the overdrive unit go bad and pressure is lost. In addition to the symptoms that you describe, both my 240s would slip INTO OD when I let off the gas and pop back into 4th when I accelerated.

Since the light stays on, stay away from the relay. It is working fine.

Look at the wires on and to the solenoid on the left side of the OD. They like to get loose and dirty, with the wires inside the insulation breaking and just the insulation holding the wire to the terminal.

With engine off, ignition on, gear lever in 4th with OD light on, wiggling the wires by the solenoid will make it click when you find the culprit(s) that are loose.

Duane

Low tranny fluid for sure will do that. I think the 4th gear switch is suspect as well. Can be changed without too much trouble.

Thanks for the info, it was indeed the tranny fluid that was low.......... I topped it off, and now my overdrive seems to be working fine.......... I have yet to go on the highway since topping off the fluid, so i'll see how my car reacts once i start going highway speed with overdrive on....

Robert

You might also want to resolder the OD relay a la Don Foster. If you're the least bit crafty with a soldering iron, it's a quick, easy, and cheap thing to try. At the very least, it won't hurt anything. (Unless you accidently solder across a gap..AMHIK.)

Tim






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Tim Smith '85 745GLE M46 w/ 83K mi