0W-20 vs 5W-20

Sierra Dan · May 6, 2019

21 minutes ago, Grumpy Bear said:

Just curious Dan. If you got that information how would it change your life? Not being a wise guy. Seriously, I want to know as your one of the more steady, levelheaded guys in the community.

Well thank you Marty! I am a fly by night engineer for a living. So my brain is always pondering, analyzing and plotting! LOL

Just about everything in life is "recommended".

There is a huge difference between recommended and "required".

If our manuals state that 0w-20 oil is "required" then I think we should all stick with that.

Otherwise what is the harm in deviating from the norm?

mookdoc6 · May 6, 2019

My wear metals are through the ROOF on 0W-20! I am switching to 20W-50 so I can play in the 6K's all day.....and not worry?

Cowpie · May 6, 2019

2 hours ago, Sierra Dan said:

Here in the middle Midwest, temps often fall below 20 in winter so if I were to switch it would be a 0w-30

I live in central Iowa and never consider anything less than 5w30. I even use a 10w30 in the wife's 2006 Cadillac CTS. Given that a 5w20 or 5w30 falls below the maximum cold flow viscosity required by the OEM down to -30C / -22F, I don't worry too much about the 5w30 doing fine. I do cheat though..... my vehicles sit in a heated garage when we are home.

My commercial trucks get 10w30 in the winter and they go to Minnesota, Dakotas, Wisconsin, Michigan, all over the upper Midwest. all winter long. My current one is at 969,000 miles and still only uses about 1 qt of oil every 11,000 miles and runs as good as new. No repairs to the engine except a couple of exhaust manifold bolts replaced.

I would probably only consider a 0w20, 0w30, etc if I were to move back to the interior of Alaska. But even then, I would use oil pan warmers. Nothing flows well at -50F.

Given that it takes more viscosity modifiers for a 0w20 or 0w30 than it does for a 5w20 or 5w30, and that while base will not break down, viscosity modifiers can do so at times. Just not worth it to me to use an oil that is designed for much colder temps than I will deal with.

Edited May 6, 2019 by Cowpie

AtlasFBG2 · May 7, 2019

20 hours ago, CamGTP said:

Someone should try some 0W16, just for the lulz and to say they did, then brag about the MPG improvement brah.

Japan's had it forever and it's now used in US on many new cars.

I went from 5w30 to 0w20 in my 4.3 v6. The MPG improvement is really not much. It does go into v4 more often though.

I might try 0w16 on the last oil change before I trade it in.

ftwhite · May 7, 2019

23 hours ago, Sierra Dan said:

Here in the middle Midwest, temps often fall below 20 in winter so if I were to switch it would be a 0w-30

So try an experiment: leave a quart or jar of each weight oil out by your truck on the colder nights. When you go to start your truck, see if you can tell the difference between the heavier stuff and the light stuff.

For me 0 weight is just too much like water when "cold". At operating temps it more like a 30w, so I just don't think it makes a difference where I am and the narrower the range, the less modifiers to go bad, wear out.