Maximizing Engine Health 5w30 vs. 5w40 - The Ultimate Guide

5w40 is thicker/more viscous, and only when warm. So 5w40 is worse fuel economy etc. It's not a huge difference though. 5w-30 is thinner / less viscous / flows more at colder temperatures than 10w-30 oil. ... Do high mileage oils make a difference? Reduced oil ... Audi A5 / S5 / RS5 (B9) - 5w30 vs 5w40 - So I have been using Castrol edge 5w40 in my 2018 A5 since birth (75k). Seems this oil is becoming ... Whether you're looking for: 5W30 fully synthetic engine oil, 5W40, 0W30 or even 0W20 engine oil, we have a wide range of options to meet your needs. Our ... Not sure which motor oil or gear oil your vehicle requires? You're not alone! Because approvals, specifications and viscosities such as 0W-30, 5W-30, ... A strict answer to the question is that the 5w40 is more designed for hotter weather. For your specific car however, it is best to check the manual. Generally speaking a 5w-40 is more expensive oil than a 5w-30 as it has to not thin out at the higher end of the temp. ranges. Personally I run ... 5w-40 is very thick in cold, which is bad for turbo apps. This is the reason for the evolution of 0w-30 and 0w-40 oils, however 5w-30 synth is ... Like 5W30, 5W40 is an oil with multiple grades. Because of the '5W', it has the same 'winter' viscosity. The '40', however, suggests that this ... ... that is optimum under a set of operating conditions. For your vehicle this might be 0w-20, or 5w-40, just fo...