Oil Viscosity

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Apr 23, 2021
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I may do it yourselfer. I prefer to do the oil change and maintenance on my vehicle myself. I work as an in the electrician and do mostly power plant maintenance so I'm mechanically inclined.
Sometimes with my job I am required to be out of town and sometimes for a long periods of time. occasionally that leaves me seeking service while out of town.
So far I haven't run into it that situation yet with my vehicle. Next oil change I'm probably going to have to get it done at a service center.
The last few vehicles I've owned have all been Ford. Ford specs 5W-20 and I know you can use 0W-20. I prefer 0W-20 and I have 0W-20 in my vehicle now.
I'm going to a Ford dealership needing service and the last time it happened I asked for 0W-20 oil and they refused to put it in. I got the standard 5W-20 semi synthetic motorcraft oil.
 
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0w-20 and 5w-20 are almost the same, 0w-20 even have a slight advantage in winter. However being a quick lube store they should tell you they ran out of 5w-20 and ask if you allow them to substitute with 0w-20. I will be upset if grocery story substitutes my order without any notice!

The real problem is the filter. Quick lube will cut cost on filter as much as they can. They are likely to use a very cheap filter w/o an anti drain-back valve, which would cause your engine running dry every time you start it. I'd suggest you do a short OCI for this oil and change it yourself with a quality filter next time.

Regarding to the oil plug, Try spray some penetrating oil around the bolt, wait for 10 minutes then lose it. I bought a Fumoto valve so I never need to remove oil plug to change oil in future.
Which quick lubes use filters without adbv’s?
 
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All 20 weight oils have the same viscosity at operating temp (100C/212F). The 0W-20 will start flowing faster after startup than the 5W-20
 

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All 20 weight oils have the same viscosity at operating temp (100C/212F). The 0W-20 will start flowing faster after startup than the 5W-20

Assuming the pump isn't on the relief and both oils are appropriate for the ambient conditions, they will flow the same. A positive displacement pump doesn't care about viscosity as long as it can get it up the pickup, however, if it is too heavy, you'll activate the relief and that will decouple the linear increase in flow with RPM as oil is bypassed back to the feed side once the pressure threshold is reached.

The Winter rating for a 5w-20 sets the Cold Cranking limit at -30C, and the pumping limit at -35C, whilst those figures are -35C and -40C for a 0w-20 respectively. If you are starting at -20C, both oils are appropriate.

However, the 0w-20 will be thinner, which means less in the way of pumping losses and less drag, which improves fuel economy slightly. Many 0w-20's are also blended with higher grade base stocks, but that's not really germane to the topic at hand, just something to be aware of.
 
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But they do overuse resources and ruin the environment. Multiply this behavior by 250M and you'll see the point.

A 3k OCI will cause more engine wear. But, as usual, something else will likely kill the car - unless it is a Kia/Hyundi
How does a 3k OCI will cause more engine wear vs 5k OCI?
 
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I generally change engine oil myself. (If you want a job done right, do it yourself.)

I have an 11-year old Ford Focus with 127,000 miles on it. I’ve changed the oil 28 times so far, always with full synthetic.

The last time I tried to change the oil I couldn’t get the plug out, even with the longest wrench I had available. The most expedient solution was to take it to a quick-lube joint. I specifically picked one that offered Mobil-1.

I told them to use 4.5 quarts of Mobil-1 5W-20.

Two hours after I got home, I pulled the dipstick. The oil-pan was a bit over-filled. (I suspect they put in 5 quarts. Either that, or they didn’t let the pan fully drain.)

When I examined the paperwork, it said Mobil-1 0W-20, not 5W-20. I was furious. I called them and they said that they no longer carry 5W-20, and 0W-20 is an acceptable alternative. So I asked them why the owner’s manual doesn’t say that. They said it’s because 0W-20 didn’t exist when the car was built.

Even if they’re right, I don’t think they had any business deviating from my request without telling me.

What do you think? Will using 0W-20 potentially cause any problems?

(By the way, the last time I had an oil analysis at Blackstone Labs at around 100,000 miles, they said, “Whatever you’re doing, just keep doing it.”)
0w-20 is a better oil, and they are correct, it's perfectly fine. They should have, however, consulted you about it before just changing the viscosity.
 
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They had to ask for your permission since you specifically requested 5w-20. Not surprising, 99% quick lube places suck.
I’d be more worried if your invoice does not match whats actually inside the car… those highschool drop outs dont care what they put in your car, you lucky it had any oil in it
 
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Sep 20, 2018
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I don't think you would notice any difference in the two.
i sure can't.....
Not defending the quick lube place but they didn't tell you any lies about the 0w20,
also your quote ( if you want a job done right do it yourself ).
who put the drain plug back in on the last oil change ?
...0W20 didn't exist when the car was built...

lol.
 
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open range
Assuming the pump isn't on the relief and both oils are appropriate for the ambient conditions, they will flow the same. A positive displacement pump doesn't care about viscosity as long as it can get it up the pickup, however, if it is too heavy, you'll activate the relief and that will decouple the linear increase in flow with RPM as oil is bypassed back to the feed side once the pressure threshold is reached.

The Winter rating for a 5w-20 sets the Cold Cranking limit at -30C, and the pumping limit at -35C, whilst those figures are -35C and -40C for a 0w-20 respectively. If you are starting at -20C, both oils are appropriate.

However, the 0w-20 will be thinner, which means less in the way of pumping losses and less drag, which improves fuel economy slightly. Many 0w-20's are also blended with higher grade base stocks, but that's not really germane to the topic at hand, just something to be aware of.

This is true. What's often overlooked, not all oils of the same nominal viscosity range are the same CCS and MRV. As a result there may exist differences in how often the bypass valve/pressure relief valve will open after a true cold start and at perhaps elevated engine speed, again resulting in unfiltered oil supplied to the engine.
While it's true, that 0W-20 are often better quality base oil, it isn't necessarily the case. A 5W-20 of the same quality but thicker base oil will likely result in lower Noack and higher flashpoint thus less chance of deposits to form on piston rings and valves.
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This is true. What's often overlooked, not all oils of the same nominal viscosity range are the same CCS and MRV. As a result there may exist differences in how often the bypass valve/pressure relief valve will open after a true cold start and at perhaps elevated engine speed, again resulting in unfiltered oil supplied to the engine.
So you're saying that as a consumer choosing an oil by grade is inadequate and we should have access to viscosity tests?
 

4WD

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This is true. What's often overlooked, not all oils of the same nominal viscosity range are the same CCS and MRV. As a result there may exist differences in how often the bypass valve/pressure relief valve will open after a true cold start and at perhaps elevated engine speed, again resulting in unfiltered oil supplied to the engine.
.
Seems like another advantage of a variable displacement pump if it can stay in low stage and avoid the bypass as the oil heats up getting out of your neighborhood etc …
 
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How does a 3k OCI will cause more engine wear vs 5k OCI?
Polar head affinity, a surface competition between EP and detergents and lubricant. Like Musical Chairs, it's a scramble when the music stops and the engine starts. Its likely not enough to worry about and engine will have the same service life regardless.
But you are not doing the engine or you wallet any favours.
 
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Polar head affinity, a surface competition between EP and detergents and lubricant. Like Musical Chairs, it's a scramble when the music stops and the engine starts. Its likely not enough to worry about and engine will have the same service life regardless.
But you are not doing the engine or you wallet any favours.
Its a crazy theory I heard before. The benefits of more frequent oil change will outweigh any theoretical crap.
 
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But they do overuse resources and ruin the environment. Multiply this behavior by 250M and you'll see the point.

A 3k OCI will cause more engine wear. But, as usual, something else will likely kill the car - unless it is a Kia/Hyundi

I hug a tree before every oil change. So me and nature .... we're good.
 
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