Originally Posted By: volk06
Originally Posted By: TheLawnRanger
I think itt's due to the combination of the heat of a small engine and 5w30 being thinner. I always use HD 30 since the manual calls for it in warmer weather and it rarely gets below freezing where I live. (not that I mow during the winter) I would use 5w30 if I had extra but with three vehicles that use it, I rarely do.
Partially correct. A 5w-30 is not thinner than a 10w-30 or a 30wt at operating temprature. The reason 5w-30 may see an increase consumption is because they have to use viscosity improvers, this in return makes the oil a little more volatile than a 10w-30 and a 30wt. The general rule of thumb is the wider the difference from Xw and the XX (Xw-XX) part, there is a potential for the oil to be more volatile. The HTHS is also typically higher on a 10w-30 and 30wt vs a 5w-30. This because the oil does not need as many viscosity improvers.
^this drop that science, son. It cracks me up when someone's or so and so's car that needs a 0w-20 gets 0w-30, 5w-30 recommended to them or worse, 10w-30. This 0w-20 I use doesn't budge on the dipstick. Neither the Honda OEM 0w-20 or the Idemitsu although I just put that in.