2007-12-31 10:10:00 · 6 answers · asked by stevenzepke 1 in Cars & Transportation ➔ Maintenance & Repairs
thinner oil flows easier for one energy conservation and tighter tolerances in between the bearings that need a thinner oil
2007-12-31 10:16:55 · answer #1 · answered by luke v 3 · 1⤊ 1⤋
5w20 delivers marginally better gas mileage, yes, which all makers want to achieve to improve their CAFE score.
But, 5w20 oil may not provide great protection if your towing a trailer, driving in hot summer temps, or climbing over mountains.
5w20 has much lower film strength, and film strength is what reduces friction, protecting your engine. The higher the temp, the greater the stress that must be born by the film strength.
5w20 is thinner and thus flows more easily when cold. As long as your owner's manual recommends it, I'd use it in late Fall, Winter and early Spring (if you live where it is regularly freezes). This thin oil will circulate quickly to protect your engine when cold starts occur.
For greater protection in late Spring, Summer and early Fall, I'd use 5w30 (as long your owner's manual lists it as an acceptable viscosity). 5w30's greater film strength provides better high temperature protection.
2008-01-03 01:31:42 · answer #2 · answered by West Coaster 4 · 0⤊ 0⤋
Lighter-weight oils improve gas mileage and makes cold-starting easier.
2007-12-31 18:40:54 · answer #3 · answered by Paul 7 · 0⤊ 0⤋
^^ same as answers above + to get better gas mileage to report "CAFE" aka. Corporate Average Fuel Economy. 5W20 doesn't have as much viscosity as 5w30 does, so there's less friction and a little better gas mileage. And by little i mean 1-5% at most. Manufacturers are doing whatever they can now though to improve overall gas mileage in their car line ups.
2007-12-31 18:17:34 · answer #4 · answered by Honda & G35_Tuner 6 · 3⤊ 0⤋
Tighter engine clearance specs. need thinner oil at start up.
2007-12-31 18:16:46 · answer #5 · answered by thebax2006 7 · 2⤊ 0⤋
Not ALL are, but quite a few. Its been proven that the lower weight oil is still plenty thick enough to protect the engine, but the big reason is during cold engine start-ups, the thinner oil gets up to the vital parts of the valve train quicker. A major manufacturer went 5w20 to its entire domestic fleet due to severe cold-engine valve guide wear, causing their engines to blow blue smoke at stoplights.
2007-12-31 18:15:39 · answer #6 · answered by ruskinflgator 5 · 1⤊ 0⤋