Where is the location of oil sending unit on a 1988 Chevy pickup?

The oil sending unit on a 1988 Chevy pickup truck is located on the passenger side of the engine block, near the oil filter. It's usually a small, cylindrical device with one or two wires connected to it. However, the exact position might vary slightly depending on the engine (e.g., a small-block V8 vs. a big-block V8 or a V6). You'll need to consult a repair manual specific to your truck's engine for the most precise location.