My question is what is the lowest temp these oils can be effective without having starting issues and does base oil change the lowest temp you can use a 5,10 and 15w, sorry if this is worded weird having a hard time forming my thought into words
Help me understand winter ratings
- Thread starter BigShug681
- Start date
OVERKILL
$100 Site Donor 2021
That's CCS (Cold Cranking Simulator) that's the one an oil usually fails first and sets the Winter rating.
So, if you look at J300:
You can see that for a 10W-xx for example, the oil has to be below 7,000cP @ -25C.
And yes, PAO is the indisputable king of cold temperature performance, since it has no wax in it, so there's no way for wax crystals to form, which are what ultimately drive-up the viscosity dramatically, and sharply, once PPD's are no longer able to hold that process off.
Interesting so are all 15W-xx for example only useable down to the same temp before you will experience issues or is each oil different?
There's always some variation between different brands and types of oil, so each weight describes a range of viscosity levels. That chart displays the maximum level of pumping pressure allowed at a given temperature for each weight for it's winter rating.
If it’s that cold I’m just not going out lol
OVERKILL
$100 Site Donor 2021
All 15W-xx's failed to be 10W-xx's, that's the easiest way to look at it. Does that help?
OT: I've never understood this sentiment. 15W is "good to" but 10W and 5W are better.
My echo did a few cold starts with 15W-40 in the low teens; The valvetrain noise was disconcerning; perhaps it was properly lubricated, but it didn't sound that way.
Yes it does
Should have heard my old power stroke or the C15 in my semi at work start on a 5 degree morning. My truck sounded rough but it was always filled with amsoil, the 10w30 that was discontinued, the C15 got whatever slop I could find to top it off with because the owner refused to fix things correctly on it and that poor rig sounded like it was going to literally come apart
Next question how do gear oils even function in Cold temps, example 75w140, id imagine it would have the consistency of grease in the low teens
OVERKILL
$100 Site Donor 2021
The Winter rating for gear oils is different from the one for engine oils. That's covered under J306:
Interesting I have a qt of Amsoil severe gear 75w140 in the freezer for observation after getting cold. The wife doesn’t understand that this is for science
Kestas
Staff member
When I was young and foolish I ran 20W-50 in my cars year round. There was one cold day in winter where I couldn't start my car. The engine wouldn't spin fast enough to start.
Remember those oils are allowed to slip one w grade while in service... A 15w can become a 20w. .. A 10w can become a 15w in service...
That can matter like when Texas saw temps below 0 degrees Fahrenheit and only 10 above over much of the state just a few years ago.
Where normally a 15w wouldn't have been a issue... It could have been if it had been in the vehicle for a long while and slipped to a 20w and it was -6 °F outside in the Texas panhandle.
That can matter like when Texas saw temps below 0 degrees Fahrenheit and only 10 above over much of the state just a few years ago.
Where normally a 15w wouldn't have been a issue... It could have been if it had been in the vehicle for a long while and slipped to a 20w and it was -6 °F outside in the Texas panhandle.
Not always true, sometimes marketing plays a factor in the weight rating on the bottle.
I've seen examples of oils that can meet/exceed a lower W rating, but are labeled for a higher grade, presumably because of consumers' misbelief that the lower number (0W for example) is too thin. They label for what sells.
Then there's the other misbelief in that a 0W oil is thinner/better at cold temps than something with a higher winter grade. Just because the oil meets the qualifications for the 0W rating, doesn't mean it's thinner at say, 0-10F, which is fairly extreme cold in most of the US. For example, someone living in Missouri who experiences temps down to 0F occassionally, a 0w-40 will often be thicker at that temp than a 5w-30. Varies by oil, but too many people fall for the 0W is better than 5W in winter, when that is not always the case.
Dang, are we that close to the end of summer that we're already contemplating winter oil choices?
I'm going to hang onto the nice weather as long as I can.
OVERKILL
$100 Site Donor 2021
Under the SAE rules, an oil must be labelled with the lowest Winter rating it meets. The only exception applies to monogrades (no VII's), which can be labelled as either their 100C grade, or also carry a Winter rating.
While that's absolutely true when discussing different grades, and heck, sometimes not even different grades, a 0W-30 with a VI of 161 is going to be heavier than a 5W-30 than a VI of 190 at any point below 100C (assuming they have the same 100C visc) until some point below 0C, it's really immaterial because as long as the Winter rating is appropriate for the ambient conditions, you'll be fine.Then there's the other misbelief in that a 0W oil is thinner/better at cold temps than something with a higher winter grade. Just because the oil meets the qualifications for the 0W rating, doesn't mean it's thinner at say, 0-10F, which is fairly extreme cold in most of the US. For example, someone living in Missouri who experiences temps down to 0F occassionally, a 0w-40 will often be thicker at that temp than a 5w-30. Varies by oil, but too many people fall for the 0W is better than 5W in winter, when that is not always the case.
Dang, are we that close to the end of summer that we're already contemplating winter oil choices?
However, it should be noted that oils ARE allowed to slip a Winter rating in service, so if you are close to the limit, it's quite possible to be out of spec after the oil has some miles on it. I've told the story of starting our Expedition with 5W-30 Pennzoil Ultra in the pan when it was -30C in Quebec and it barely rolled over, I didn't think it was going to start. The same temp with M1 0W-30, and it started just fine.
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You are probably lucky. Had it started but not been able to pump the outcome would’ve been much worse.
When would an oil become unable to be pumped? For instance would a 15W-xx have this happen under -13 F or would this be a much lower temp such as an oils pour point
0wXX= 
5wXX=
10wXX
15wXX
Hope this helps...
5wXX=
10wXX
15wXX
Hope this helps...
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