My truck is a 98 150 4x4 with automatic transmission and occasionally while driving down the road the OD light on the shift lever will start flashing, the transmission still performs just like normal, no change as far as that is concerned, just the light flashing. The light will stop flashing the next time u start the truck. and it might be a couple weeks or a couple months before it comes back on. the owners manual does not have any info on why this light would flash?

 

It flashes because something is wrong with the transmission. You need to have the codes read to find out what's wrong.

 

Mine does the same thing every now and then but my transmission revs up to around 3800 RPMs before shifting sometimes and sometimes I have to let completely off the gas for it to shift. The truck has 154000 miles on it. Does anyone think its a really serious problem or anything? Thanks

 

Both of you guys - go find a shop that has a code reader that can read Ford tranny codes.