I have a 95 1 ton 4x4 12 valve which i use alot. Well the other day after haulin in a big load of iron and then my calves the tranny all of a sudden started sounding like that ole 55 chevy on two lane blacktop. Well checked the fluid and it was low. So stuck some gear oil in it thinkin it would quiet it down. Still the same and am in a dilema. Checked the price of a used one and they are crazy priced for a used one.. Anyone got any ideas like is it hard to fix one. The gears all work, jus noisy..

 

You can't really be sure until you tear it down. I'd find a local trans shop and see how much it would cost to have them tear it apart to see what exactly is going out on it.