However, some considerations:
* Climate: In hotter climates, a straight 40 weight might be considered, though this is less common now. In colder climates, a 10W-40 or even a 15W-40 might be preferred for easier starting.
* Engine Wear: If the engine has significant wear, a slightly thicker oil (like 20W-50) might help compensate for increased clearances, but this should be done cautiously and ideally after consulting a mechanic.
* Modern Oils: Modern oils often exceed the specifications of older oils, meaning a modern 20W-40 meeting the required API specifications (check your owner's manual) will likely be fine.
In short: Start with 20W-40. If you experience problems (e.g., excessive oil consumption or noisy operation) then consider consulting a mechanic experienced with classic cars to determine the best weight for your specific situation. Always check your owner's manual for the manufacturer's recommendations.
