* Older Models (pre-emissions standards): These likely didn't have an air pump.
* Models with Emission Controls: Many K10s, particularly those from the late 1970s through the mid-1980s (depending on the specific engine and emissions regulations in effect at the time), had an air pump (also known as a smog pump or Positive Crankcase Ventilation - PCV pump) as part of their emissions system. If the truck originally came with one, removing it without also modifying or removing other related components will likely cause it to fail emissions testing.
In short: If your K10 *has* an air pump, you might need it to pass emissions. If it *doesn't* have one, you don't need it. If you're unsure, check your owner's manual or look under the hood to see if one is present.
