However, generally speaking, a 2000 Chevy Blazer likely uses one of the following:
* 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: Also a possibility, especially if you live in a warmer climate.
Crucially: The owner's manual will specify the *type* of oil (conventional, synthetic blend, or full synthetic) as well as the viscosity. Using the wrong type or viscosity can damage your engine. Always consult your owner's manual before changing your oil.