best engine oil for older cars

Older engines appreciate a slightly thicker brew—think 10W‑40, 15W‑40 or 20W‑50 depending on climate and wear—rather than ultra‑thin modern 0W‑20 stuff.

For classics with flat‑tappet cams, choose oil with higher ZDDP (zinc) levels or a reputable additive, or you’ll be polishing lobes instead of bragging about them.

A quality mineral or semi‑synthetic “high‑mileage” oil helps with seal conditioning and leaks, while full‑synthetic is fine if the gaskets aren’t already weeping like a soap opera finale.

Change it more often than you used to—time and short trips kill oil—use a good filter, and always follow the owner’s manual viscosity guidelines first. Consult official documentation for exact figures.