I'm sure the cited expert really is an expert, but this article fails miserably at conveying any cohesive understanding from them to you. It's full of conclusions that don't follow from their leading statements.
My understanding about warming up an engine before putting load on it had nothing to do with fuel or power steering fluid, it was about thermal expansion of all the machined parts that suffer wear if they are run under load while they are loose-fitting from being cold. This is a thing even in summer and merely worse in winter.
This article barely talks about this and doesn't say anything intelligible but just says "stress" from stepping on it right away.
Maybe that issue also no longer exists on modern engines, but nothing in this article explains that.
Mostly everything this says about why idling is supposedly bad, applies to operating the thing at all, idling or not. The conclusion would be "don't use your car at all in winter"
Well, if you're going to use it at all, then you're already doing the damage, so you might as well be comfortable and have an easier time clearing the windows. The device only exists in the first place to serve you.
I have the same recommendation on my car user manual, don't warm the engine, but take off after start up and take it slow for a few minutes until the engine water moves off the base.
I know one of the engineers that worked at the car design and when questioned, he explained (going off memory here) that people used to warm the engine, then started driving normally, and while the engine is hot, the trasmission and differentials aren't, but you don't have a good way of warming them up while standing still, so drive off slowly and carefully without asking full torque from your engine, and it will help warm the whole thing.
Yeah, from my understanding, basically try to keep the engine load light until at least you’ve warmed your coolant to operating temperature, but ideally 5-10 minutes beyond that as your oil(s) will take longer to heat as they’re more viscous than coolant.
Basically, drive like a grandma for ~10-20 minutes before even moderately giving it the business.
The flip side of this is that, especially if you’ve got direct port fuel injection, you’ll actually want to give it the business on occasion (once properly warmed up) for best operation, as the detergent from an increased fuel spray can help to break up carbon buildup on the top of your pistons. Either way you’ll likely want to book in carbon cleanup as a periodic maintenance item.
It's like lithium ion batteries. There is a set of "rules" for taking the best possible care of the battery, but you mostly can't actually follow them, while still getting any utility out of them since adhering to them strictly is almost more effort than living without a battery.
So all that's reasonable is simply to be aware of the ideals, and by inference the anti-ideals, and let them guide whatever freedom you do have, while just using the thing however you need to.
If you need to actually use your laptop on batteries freque tly, then go ahead and allow it to charge to 100% instead of limiting it to 50% to 80%. If you live somewhere cold and need to use a device in the cold, well then you just go ahead and use it outside of the ideal temperature range.
But the knowledge is still useful because there are still plenty of times where you could do any number of things and don't much care which since they're all equal effort, but they aren't all equally good for your equipment, and all else being equal, you would be just as happy to adopt a habit that gives x extra years of lufe than one that removes x years of life, if you simply knew about it.
Like, you don't really care that much where in your house you plop some device when you're not using it for weeks at a time, but a shelf in a covered cabinet is better than a table in direct sunlight, is better than sitting directly on top of a steam radiator.
Your work commute precludes the absolute ideal, but within your limits there is still a lot of opportunity to do things more vs less optimally. You might intentionally take local roads to the next exit, or for merely 10 miles even the whole way.
Or just don't even worry about it at all because diffs and trannies are really not what die first or most, and trannies do warm up some just from the torque converter pumping and the radiator loop.
And manuals just aren't a problem no matter what. They may shift harder but they aren't being hurt much. In any climate that even has cold, everything else will rust to junk before a manual tranny even needs a new clutch let alone any kind of actual wear to the gears or synchros.
Honestly, the other commenter hit the nail on the head in that "optimum" doesn't mean "necessary"—but 10 minutes of a commute isn't enough to get your engine fully up to working temperature and you are shortening its lifespan. Maybe it doesn't matter to you, and that's totally fine. If you're changing vehicles every couple of years you're probably not even going to run into needing significant repairs as a result of it, but if you're planning on keeping your vehicles for a longer period of time it's definitely something you should consider.
Oil pressure seems to be left out of the conversation - oil-starved journal bearings can be bad news if loaded immediately. SOP in piston-engine aircraft is to get the oil temperature and pressure "in the green" before doing run-ups.
Having a water jacket around the cylinder makes it less possible for the cylinder to heat (and change size) unevenly versus an air(/oil)-cooled engine. That same water jacket permits the tolerances to be set to assume a maximum head temp under 300°F (versus 460°F for airplanes). That means the steel rings don’t have to deal with as much dissimilar expansion as the aluminum heads and pistons. This allows engineers to choose tolerances accordingly. It’s not so much modern metallurgy or electronic controls, but a factor of having a lower temperature range.
I don't see how water jackets, pistons rings, and their tolerances are directly relevant here. The topic was bearings, and their lubrication and wear, in the larger context of warming up your car before driving in cold weather.
Imagine a cold-soaked engine with an aluminum piston, steel rings, a cast iron sleeve in an aluminum head. The aluminum piston will heat very quickly compared to the cast iron sleeve in an air-cooled engine. (There’s a massive aluminum heat sink in the form of the cylinder head.)
For a water cooled engine, there is a water passage around 3/16” from the cylinder wall which helps to bring the cylinder up to an even temperature more quickly and prevents a high heat flux from expanding the piston to the point where it can scuff the walls.
It’s not only oil pressure that is a concern for a cold-start to operating temps.
My 2018 car (gasoline, turbocharged, direct injection) has coolant and oil temp readouts. The increase in coolant temp from a cold start leads the oil temp by a few minutes (exact time is dependent on ambient temperature and load profile).
Once the oil temp starts to get above 150F it very quickly gets to the operating temp (220F), so I view that as the point that it's okay to go above 3000 RPM.
If there are oil heaters then they must be far away from the oil reservoir temperature sensor and only have a local effect. As you say, that sounds like a feature for very large engines. It's probably a good practice to be gentle to car engines with cold oil.
Street cars have been using coolant/oil heat exchangers to bring oil up to temp faster and regulate its temperature under load since at least 1999 (source: VW's 1.8T, AEB and AWP motors).
The most common heater of an industrial engine is for the jacket water. Keeping the entire block heat soaked is the easiest/safest way to heat the oil as well. Using a "prelube pump", which is a low pressure, low volume circulation pump that parallels the main engine driven pump, oil is continuously sent throughout the internal passages
Unlikely to be starved, (unless it’s really cold and then you barely have any oil), but bearings can be washed out by high oil pressure, which is a consideration with cold oil.
If your engine doesn't have oil pressure before it's even finished starting, either it's a bit faulty or you're using a grossly incorrect grade of oil.
I work on the repairs side of this industry (diagnostic tools), and have come to the conclusion that while the thermal expansion is an issue, it’s probably not the largest or most fundamental one.
When an engine idles (with no load), it produces relatively little heat. Comparatively, an engine running faster, under load produces much more heat. The engine will warm up more quickly and less evenly when loaded, likely leading to thermal stress, and possible mismatched thermal expansion. On the other hand, modern lubricants are very good at handling different temperatures.
The other thing to consider is that the engine is only one part of the vehicle, and various other components of the drivetrain may actually suffer more thermal stress from the idling than from immediate driving.
Absolutely. The risk of putting load on the engine before the moving parts and oil have reached operating temps is far greater than the threat of tiny amounts of gasoline washing residual oil from the cylinder walls or thinning the oil.
The only risk described here applies to prolonged idling only and is a long term risk mitigated by reasonable elwarmuo and oil changes. The short term risk is the rotating assembly and value train is far more immediate.
Fuel injection has convinced people that they can just jump in a cold car, fire it up and be fine. Doing so, especially in extreme cold is just incredibly damaging.
I work in this industry (designing tools for automotive diagnostics), and have heard many arguments either way WRT warming up engines; I do not understand yours.
Modern vehicles have high quality oils, tight tolerances but rpm dependent oil pumps. At idle, the oil pressure is lowest, the fuel energy is lowest and consequently the engine will take the longest to come up to operating temperature.
I thought it was just me because I'm not an expert on engines, but apparently not.
And I agree with your last point, it was the other thing that was bothering me by it. What exactly is actionable here, to me it's just normal wear and tear.
My understanding about warming up an engine before putting load on it had nothing to do with fuel or power steering fluid, it was about thermal expansion of all the machined parts that suffer wear if they are run under load while they are loose-fitting from being cold. This is a thing even in summer and merely worse in winter.
This article barely talks about this and doesn't say anything intelligible but just says "stress" from stepping on it right away.
Maybe that issue also no longer exists on modern engines, but nothing in this article explains that.
Mostly everything this says about why idling is supposedly bad, applies to operating the thing at all, idling or not. The conclusion would be "don't use your car at all in winter"
Well, if you're going to use it at all, then you're already doing the damage, so you might as well be comfortable and have an easier time clearing the windows. The device only exists in the first place to serve you.