40 is thicker. 20w 40 means its 40 weight at normal and hot temps and 20 weight at winter temperatures. 40 stays 40 at all times.
In my beetle I run SAE30 oil in winter, SAE40 in summer. I change oild religiously at 3K minle intervals without fail. Aircooleds don't seem to like multi-viscosity oils. If it's below freezing out the SAE20W oil is called for.
10w40 is thicker (but only when hot, they are the same thickness cold.)
That means the oil is 15 weight when cold and 40 weight when hot. The higher the number the thicker the oil.
In cooler temperatures it's ok, but in hot weather run a thicker oil.
20W50 is the " thicker " oil
5W-30 is when it's hot. They are the same when both are cold.
The higher the number the thicker the oil.
According to the manual it takes .625 of a quart and manufacturer recommendation is 5w-30. If it is an older engine that smokes you can use SAE40 to keep the oil from slipping past the rings.
Engine oil does not get "thicker" at high temperatures it gets thinner.
No, multi-viscosity oil does not get thicker when it's hot; rather, it becomes thinner. Multi-viscosity oils are designed to maintain their effectiveness over a range of temperatures. For example, a 10W-30 oil has a lower viscosity when cold (10W) and a higher viscosity when warm (30), allowing it to perform well in both cold and hot conditions. Thus, while the oil's viscosity changes with temperature, it is formulated to ensure optimal lubrication in various environments.
when oil gets hot the particles break down that means it thins out when cold they bunch together making it weigh more or thicker
10w30 is thicker than 5w20