katrina,
What year/brand truck do you have? I found one of your posts where you mention 1940.
The 1940 Chevrolet Truck Owner's Manual shows 5 qts for regular oil change. Added to this would be the amount needed for the filter that is being used.
Most of the AC accessory oil filters were 1-qt, but a 2-qt AC filter was usually also available.
The oil-filter instruction sheets (and Owner's/Operator's Manuals) usually state to run the engine, then stop the engine, let the oil settle, and then fill to the line on the dip-stick (I assume this is for filters that do not drain to the bottom). Some instruction sheets state to add one or two quarts (depending on the filter) to the normal addition/amount of oil at an oil change.
http://www.stovebolt.com/techtips/engines/oil%20filters/index.html#isSome people who have filters that do not drain to the bottom (all of mine are like this), empty the oil pan and empty the canister. Then we add the normal amount of oil to the oil pan and one or two quarts to the oil canister (with new filter cartridge in place) before we seal the canister. This might get oil circulating through the engine more quickly.
