Shifting problem

I have a '93 Ranger with the 2.3 and a 5spd tranny. Every once in a while when I back up and try to shift into first, or any forward gear, I'm not able to. As soon as I shift back into reverse I can then shift into first gear. Sometimes when I have to go back to reverse the gears will grind as it slips into gear. Does anyone have an idea of what might be going on?

What kind of tranmission fluid do you use? I'd replace whatever you're using with MT-90 or GM Synchromesh. The latter works wonders, you'd be surprised how much more crisp your shifts are... unless your tranmission is too far gone.

I'm not sure what was in there before, but I drained about half to see what it looked like and filled it up with automatic tranny fluid which is what a teacher reccomended.