I own a 88 F250 that I ordered new. It is a farm truck that I us pulling stock trailers and hay. The truck is in very good condition for its age with only 96k miles. I don't drive it all the time because it has a 460 with 4:10 lim. slip front and rear, it may sit at my pasture a month or two at a time before it would be needed. My problem is sometimes it is hard to shift into 2nd. or rev. I had sometime tell me to change out the trans. fluid, fill it with diesel and drive it a very short while to free up the syc. from sticking. Then refill with trans. fluid and it may help the shifting. I am not a mech. and don't want to harm the trans. Also what fluid is used in that 5 speed? Any help would be app. Thanks Bobby