SAE 10w30 is better for lower temp and SAE 20w40 is the opposite better hotter temps.Thanks
The weight of the oil and flow rate. The 5w30 will flow easier when cold than the 20w40. It is 5 weight oil when cold whereas the other is 20 weight when cold. When the oil reaches full operating temperature the 5w30 is 30 weight oil and the 20w40 is 40 weight.
20W40 with no friction modifiers is what is called out for my XJ600s
best is 20w40 grade engine oil.
Use only what the manufacture recommends and nothing else.
Mixing oil weights is a NO,NO.
20w40 shell oil in summer and a 10w40 shell oil for winters is just fine
No, use exactly what Cummins recommends and nothing else.
10w-30 is reccomended in the owners manual.
The manual say 20w40 but I use 10w40 normal motor oil with any trouble.
In owners manual it said 10W40 from 10-90 degrees outside. Or 0 and up 20W40.
10W 30. The lower the number, the lower the viscosity or 'thickness'. Lower number means thinner oil at the same temperature