10W30 vs 10W40 The Essential Guide to Engine Oil Selection

Hello. I have a mildly built 350 in a 76 Monte Carlo. I put 10w30 in instead of 10w40. Will this hurt my engine? As others have said you can use both grades in any Honda bike however if you run 10-30 you may see better mpg since 10-40 is a slightly heaver ... 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. Definitely 10w30. As long as you are not enduro racing in the heat of the summer, 30 weight is fine. Whereas thick oil when cold provides less ... Researching which oil I'm going to use on my '12 1KRR, and page 138 of the manual says 10W-30 JASO MA, but goes on to list Honda GN4.. Well, which is it? GN4 is 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. This video offers an in-depth comparison between 10W-30 and 5W-40 engine oils, analyzing their viscosity ratings, characteristics, ... 10W30 has the viscosity of 10W at 0°F but doesn't thin out any more than a base 30 oil at 212°F. 10W40 also has the viscosity of 10W at 0°F but ... 10w30 will give you a bit better protection during the summer when it gets warm and 5w30 during the winter if it gets cold. Top ... The 40 weight will protect you year round for what you do;-it only has certain factors to the heat build up;-ambient temp and other component ...