Look for a blown oil cooler line. If you shut it down right away, you may not have much damage. Hppefully you meant 4 quarts of oil not 4 gallons. Being under that kind of stress, it would be an easy mis-type.

Are your motor mounts worn? Under torque, with worn mounts, one of the belts can wear into the oil cooler line causing a sudden failure even if you have seen no seepage.

I needed a 1 1/16" modified box end (cut a small portion out with a dremel cut of blade and make it a flare wrench) and a narrow line wrench to hold the coupling at the oil filter housing for the oil cooler lines. Also, taking the bottom bolt out of the drivers side motor mount and jacking the engine, about an inch, made it easier to snake the lines in and out.

If it is a blown oil cooler line, do not drive it until you can replace or you will ruin your engine for sure.

__________________
Sam

84 300SD 350K+ miles ( Blue Belle )