* 2.3L 4-cylinder: This engine typically holds around 4-5 quarts.
* 5.0L V8: This engine typically holds around 5-6 quarts.
Check your owner's manual for the exact capacity for your specific engine. The information should be clearly stated there. If you don't have the owner's manual, you can often find a PDF version online through a Ford parts website or a Mustang enthusiast forum by specifying the engine code (which is usually found on a sticker under the hood or on the engine itself).