Posted on 11/28/2025

Fresh oil is cheap insurance. Letting it slide for a few thousand miles might feel harmless, but modern engines depend on clean, correctly graded oil to cool, lubricate, and seal tight tolerances. When oil is old, thin, or contaminated, small problems snowball into accelerated wear, sticky valves, and expensive repairs. Here is what really happens inside the engine when oil service gets pushed off the calendar. What Engine Oil Actually Does Beyond “Lubrication” Oil forms a film that keeps metal parts from touching, but it also carries heat away from hot spots like cam lobes and turbo bearings. Detergents suspend soot and varnish so the filter can trap them, and anti-wear additives protect during cold starts before full pressure builds. The oil also helps seal piston rings, which maintains compression and power. When that chemistry breaks down, friction rises, temperatures climb, and deposits start to stick where they should not. How Oil Degrade ... read more