I just installed a switch to manually lock the torque converter and it works great, but tonight when I was driving home from work I had it switched on and noticed the od switch light came on but it didn't kick out of od, so I turned the lockup switch off and right away it went out of overdrive. I hit the overdrive switch and it went back in to od. Didn't have any more issues the rest of the way home. Am I correct in assuming that the lockup switch has nothing to do with overdrive. I'm thinking that my TPS must be pretty well trashed and was trying to avoid buying a new one right before a 1000 mi trip. This is on a 95 with a 47rh tranny.

 

In the 17 years I've owned my 2500 it's done the same thing about a dozen times.
I always figured it was some sort of computer glitch.
Don't think it has anything at all to do with the lockup switch.