What kind of oil do you put in 2003 Chevy Avalanche?

The type of oil for your 2003 Chevy Avalanche depends on the engine it has. The Avalanche came with several engine options that year. To know for sure, check your owner's manual. It will specify the exact type and viscosity of oil recommended by the manufacturer.

However, generally, a 2003 Chevy Avalanche would use either:

* 5W-30: This is a common viscosity for many vehicles, and likely a good starting point if you don't have your owner's manual.

* 10W-30: This is another common viscosity, but potentially less ideal in very cold climates.

Crucially, the owner's manual will also specify the oil type (conventional, synthetic blend, or full synthetic). Using the incorrect type or viscosity can damage your engine. Don't rely solely on this information; consult your owner's manual.