Oil & Fluids

Oil & Fluids answers from Piston Journal: troubleshooting fixes, step-by-step how-tos, comparisons and quick facts, each with the short answer first.

Oil & Fluids

Coolant vs Refrigerant: What Each Fluid Does in Your Car

Coolant vs refrigerant: coolant keeps the engine at temperature; refrigerant runs the A/C in a sealed loop. See how they differ and why they never mix.

Oil & Fluids

What Is Engine Oil Cooler? How It Works, Types and Leaks

What is engine oil cooler hardware? A small heat exchanger that keeps oil near a steady temperature. How it works, the two types, and signs it is failing.