The oil capacity for a 1998 Chevy Cavalier depends on the engine. There were several engines offered that year. To know for sure, you need to check your owner's manual or look at a sticker usually located under the hood (often on the oil filler cap or elsewhere).
However, the most common capacities are:
* 2.2L 4-cylinder: Around 4 quarts.
* 2.4L 4-cylinder: Around 4 quarts.
Always check your specific vehicle's documentation for the precise amount. Adding too much oil is just as bad as adding too little.