1988 Other Mitsubishi Models overdrive will not engage

I have a very similar problem. I drive with the O/D off for 3 months now. When and if I find out the cause I will email you. Please do the same. My car is 6 cyl. Mitsubishi Emeraude 1998, 2000 cc or so. See I am in Japan and they have different system of counting the years so I am giving you my best guess. So confusing.

It was suggested that I change the fluid and clean the system. In Japan that costs 300 dollars and there is no guarantee that it will work.

Good Luck