What oil does a 91 Caprice take?
The 1991 Chevrolet Caprice generally uses conventional engine oil, with 5W-30 as the standard grade for typical driving conditions. The exact requirement depends on the engine variant (5.0L or 5.7L) and your climate, so always verify the specification in the owner’s manual or on the under-hood oil fill sticker.
Engine options and oil basics
In 1991, the Caprice was offered with two V8 engines in the U.S. market: a 5.0-liter small-block and a 5.7-liter big-block. While both share similar oil-type expectations, the capacity and occasional grade nuance differ. The following guidelines cover both engines and common climates.
Engine oil grade recommendations by climate and service
- General use: 5W-30 conventional engine oil for most temperatures and driving conditions.
- Hot climates or severe service: 10W-30 or 10W-40 as appropriate; always confirm with the manual.
- Optional: Synthetic 5W-30 or 0W-30 can be used if preferred, though it is not required by stock recommendations.
In practice, many owners run 5W-30 successfully; for hotter climates or wider temperature ranges, 10W-30 or 10W-40 may be more suitable. Always verify the exact spec for your engine code in the manual.
Oil capacity and fill specifics
Oil capacity depends on the engine: roughly 5 quarts with a filter for the 5.0L and about 6 quarts with a filter for the 5.7L. Use the appropriate oil filter and recheck the level after filling.
Oil capacity by engine type
- 5.0L (304/305) V8: ~5 quarts with filter.
- 5.7L (350) V8: ~6 quarts with filter.
After changing the oil, run the engine, park on level ground, wait a few minutes, then recheck and top up as needed to reach the full mark on the dipstick.
Practical tips and caveats
To help protect the engine over time, adhere to the recommended oil-change interval for your driving. In a 1991 Caprice with conventional oil, many owners follow a 3,000–4,000 mile interval under normal conditions; with synthetic oil or heavy use, intervals may be extended per the oil manufacturer’s guidelines and the owner’s manual.
Summary
For a 1991 Caprice, the typical specification is conventional 5W-30 engine oil, with an approximate capacity of 5 quarts on the 5.0L engine and about 6 quarts on the 5.7L engine. Climate, driving style, and engine condition influence the final grade and capacity. Always confirm the exact requirements in the owner’s manual or on the vehicle’s under-hood label to ensure full compliance.
