Is it bad if you put 6 quarts of oil in 2001 V8 Chevy silverado truck?

Yes, that's bad. A 2001 Chevy Silverado V8 typically requires between 5 and 6 quarts of oil, depending on the specific engine and whether it has an oil filter change. Putting in 6 quarts when it only needs 5 (or even slightly less than 6) will overfill the engine. Overfilling can cause:

* Oil foaming: Excess oil can churn and create foam, reducing its lubricating properties.

* Seal damage: The excess pressure can damage seals and gaskets, leading to leaks.

* Crankshaft damage: The crankshaft can churn the excess oil, leading to excessive wear.

* Damage to the PCV system: Positive crankcase ventilation system can be overwhelmed.

You should immediately drain at least some of the oil to get the level within the recommended range. Check your owner's manual for the precise oil capacity for your specific engine. If you're unsure, consult a qualified mechanic.