chevy truck brakes

I don't have a 3/4 ton, but unless its like any other drum brakes, this is how to approach it (from my exerience):

1. Work at it. Make sure the parking brake isn't on, make sure you can turn the drum freely (may have to jack up the other side).
2. Rock it back and forth while tugging at it. (You should probably remove the wheel before step one. Ha ha)
3. Tap at the edge, towards yourself, as you turn it. This sometimes pops them off.
4. At the bottom of the backing plate (on the axle side), look for a small metal knock out or rubber plug. Remove it. Using a special tool (looks like a cross between a spoon and a lever), back the star-wheel adjuster up while holding the spring loaded lever back (sometimes I have to use a second tool for this, so it gets crowded!).
5. The more you back off that auto-adjuster, the easier it should be to turn.
6. Once upon a time I had a drum brake so far gone that the shoes were jammed inside the drums and backing the star adjust made no difference (thanks mom). We had to use pry bars and wound up breaking the spings and the ears on the wheel cylinder. This should NOT be neccessary for you. Hopefully.

Let me know if you need further clarification, and remember, I've never done a 3/4 ton, so I don't know if its different.

A Different Jeff

knockout, you must get a rubber plug from the parts store to fill in the hole.

Ugh, I MUST proofread.