Autozone guy trying to confuse me

Yep.…

About 15 years ago, I had a mechanic at the Navy Exchange try and stop me from buying 0W30 Castrol (much loved on BITOG) on clearance.

“That zero weight won’t give you enough oil pressure on start up. It’s too thin. You need a 10W30.”

He was honestly trying to be helpful. And we talked for a bit, but he stuck to that point of: it is too thin on start up. I thanked him, moved to another row in the oil aisle.

And when he went back out to the service bay, grabbed two cases of that Castrol 0W30 that was on clearance.
You to him...

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I can't tell you how many times I've heard "bro...don't run that 0 weight...it's like water and will ruin your engine." This topic is definitely misunderstood by most folks confusing the "w" for "weight" vs. "winter".
 
I bought a quart of rotella 15-40 for my lawn mower and he started to argue with me about the thickness of the oil. I said the 15 is the viscosity of the oil in cold and the 40 is the weight at operating temp. He said he’s changed thousands of gallons of oil and oil is always thinner when hot than cold, basically saying I had the numbers of the weight backwards…
Lawn mowers for years used a 30w non-detergent oil. They are a ‘splash n scoop’ system with no pump. Oils today are more advanced in lubricating qualities but if you live in a 4 season area and still mow in colder months I would seriously use something like a 10w30 . Remember how thick oil pours when it’s 35-40 deg outside. Imagine a splash/scoop motor trying to pick up that glue to lube itself till the oil thins out. If you have extremely warm summers you can rotate your oil viscosity as I do in my vehicles. I run 10w40 winters 20/50 summers in az . Just an fyi is your mower a diesel?
 
I think we should start a change within our own community, which is you know... dedicated to oil, before we start complaining about random strangers in an oil isle.

I see it time and time again people referring to 0W, 5W, etc as a weight and it is rarely corrected here. People ask constantly which "weight" should they run, like 0w20 or 5w20.

I think we should start using the correct terms ourselves first.
 
0 weight oils like my 2012 focus is supposed to have 0w20 maybe the first 50-75 K miles these motor clearances loosen over time. @ 90k used 10w30 now 110k 10/40 summer 10/30 winter , just remember these oil viscosity recommendations of manufactures if followed for the life of the care will be a short life so you’ll buy another car from them because in 150k miles you’ve worn out the motor using to light of oil after all internal clearances become larger with age lowing oil pressures and loosing lubricant stability premature wearing out which a rebuilt engine will cost more than the vehicles bluebook Value pointing you back to the dealer sooner than you really wanted too.
 
0 weight oils like my 2012 focus is supposed to have 0w20 maybe the first 50-75 K miles these motor clearances loosen over time. @ 90k used 10w30 now 110k 10/40 summer 10/30 winter , just remember these oil viscosity recommendations of manufactures if followed for the life of the care will be a short life so you’ll buy another car from them because in 150k miles you’ve worn out the motor using to light of oil after all internal clearances become larger with age lowing oil pressures and loosing lubricant stability premature wearing out which a rebuilt engine will cost more than the vehicles bluebook Value pointing you back to the dealer sooner than you really wanted too.
Did you read anything in this thread before posting that?
 
0 weight oils like my 2012 focus is supposed to have 0w20 maybe the first 50-75 K miles these motor clearances loosen over time. @ 90k used 10w30 now 110k 10/40 summer 10/30 winter , just remember these oil viscosity recommendations of manufactures if followed for the life of the care will be a short life so you’ll buy another car from them because in 150k miles you’ve worn out the motor using to light of oil after all internal clearances become larger with age lowing oil pressures and loosing lubricant stability premature wearing out which a rebuilt engine will cost more than the vehicles bluebook Value pointing you back to the dealer sooner than you really wanted too.
There is no truth to this I'm afraid but a good scary BITOG goodnight story that is propagated over and over here....thin oils only for EPA CAFE requirements ruin cars early. Stop the madness. Also your 2012 should call for 5W20 not 0W but it makes no difference here.

My 2013 Focus happily driving along at 130K on a diet of 5W20. Most of that time/mileage with Motorcraft syn blend with an average OCI of ~6K. No measurable consumption. Drives basically like new.
 
I think we should start a change within our own community, which is you know... dedicated to oil, before we start complaining about random strangers in an oil isle.

I see it time and time again people referring to 0W, 5W, etc as a weight and it is rarely corrected here. People ask constantly which "weight" should they run, like 0w20 or 5w20.

I think we should start using the correct terms ourselves first.
Amen. I do it as well sometimes using weight when I should say grade.

Much different to say "Your car calls for a 30 grade oil and you can choose the winter rating either 0/5/10 based on the average low winter temps you experience."
 
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wait til you tell him about Redline Oil and it's 5w30 being thicker than a 10w40 petroleum at operating temperature 🌡️. Even the viscosity chart comparison between oils overlap and there are some 20s that are thicker, possibly performing better than the low end of where 30w start.

I do think 🤔 deep down he was trying to be helpful. It isn't like he was telling you that his quart of Mobil 1 was better than Walmart and their M1 because it's the parts store edition.
 
wait til you tell him about Redline Oil and it's 5w30 being thicker than a 10w40 petroleum at operating temperature 🌡️. Even the viscosity chart comparison between oils overlap and there are some 20s that are thicker, possibly performing better than the low end of where 30w start.

I do think 🤔 deep down he was trying to be helpful. It isn't like he was telling you that his quart of Mobil 1 was better than Walmart and their M1 because it's the parts store edition.
Yea he was trying to be helpful. He wasn’t rude or mean about it
 
Sometimes the reddit posts I see are outragous, like "if you but anything but 0w20 in there your engine will wear and explode." smh.
 
Of course it does, I think he thought the 15w was the hot number and the 40 was the cold, because oil gets thinner when hot so that meant it was a 15 hot and thicker cold, so it’s 40
Just think how crazy he would have thought you were if you told him that "W" in 15W meant "Winter". And the "Winter" grade means it's a cold condtions start-up rating of the oil. Which has absolutely noting to do with the "40" grade (hot and thinner KV100) viscosity.
 
10W-30 = 10Wal-Mart-30

We have a AutoZone less than half a mile away from Wal-Mart and exact same 5 qt. jug of oil (e.g. M1 EP, Valvoline EP, Castrol Euro) is about $8-10 cheaper at Wal-Mart. Not kidding!

That's because Wal-Mart produces and is the supplier of oil to the auto parts stores. It's an industry secret I should not be sharing but since we are bitog family, I'll tell you the real meaning of W. It stands for Wal-Mart and not Weight or Winter. :alien:
 
To further reduce confusion (Thin 30, Thick 30, Thin 40, etc.), why not xW-HTHS?

I believe there's a few people on this site who agree that HTHS should have taken precedent with oil labelling.

Certainly a way to intermingle HTHS and the lowest temperature the oil is capable of being used might have been better.

The issue is, how would you change it now after so many decades of using the same (albeit poor) system?
 
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