10w30 vs. 10w40 The Ultimate Guide to Oil Viscosity

The difference between 10W-30 and a 10W-40 is the high temperature viscosity. Obviously, a 10W-40 is thicker than a 10W-30 at high temperature. Armed with ... ... 10W-30 (51). 10W-40 (26). 10W-60 (3). 15W-40 (25). 15W-50 (8). ... 10W-30 API SL. FULLY SYNTHETIC 0W-20 API SN. SERVICE CENTRE & HIGHSTREET. Availability: 3L & 3.5L 3L 3.5L. Excellent wear protection with enhanced antioxidant ... The SUS viscosity is the same for both, but the 10W40 has more fortifiers to maintain the viscosity at higher temperatures. The bottom line is the 10W-30 is fine unless you expect ambient temperatures to approach or exceed 30°C (86°F) when you'll be better off with the 10W-40. Elite Member ... The first number is its cold start viscosity. The higher the number, the thicker the oil. In really cold climates, 0w-something ... A 10W30 is a 10 weight when cold and a 30 weight when hot, but a hot 30 weight is still a hell of a lot thinner than a cold 10 weight. The high detergent in Diesel oils like 15/40 had a counter-effect on the zddp additive. Essentially a higher level of zzdp was required in those oils. First service on mine 8 yrs ago, I went to a Honda dealer in OH and told them what I had and needed the stuff for an oil change. They gave me a ... Very generally speaking, the first number indicates the oil viscosity in cold weather. You can remember this because of the 'W', for winter. The ...