High Mileage Engine Oil Question

“Kinda confusing…”

First, find out what kind of oil is recommended for your car.
You can get this from the manual, or even the oil cap where you pour the oil in.
You absolutely should be checking the oil level between oil changes. I do it every 1000 miles.
It’s normal for a car with 190k miles to need oil between changes.
Add oil to keep the level at the top, full mark.

Let’s assume you are checking the oil well after it has a chance for all of it to run down into the oil pan and not after a long trip where boiling the moisture off will give you a lower reading. And, you are checking on level ground…If the oil is only slightly down but not enough to add oil between changes, continue the same routine you are on. Personally, I feel 3k is too soon and have more trouble free miles from longer change intervals; but, not to worry . Don’t obsess and use the oil recommended in your manual. Varying from what’s recommended is not worth it except under extreme conditions.

Might want to check your manual again. Are you sure its not 5-30 when its below 20 degrees and 10-30 above 20? At any rate just keep using what the manual says to use and check your oil to make sure it doesn’t get below 1 quart low. Using some oil is normal. On my Buick with 530,000 on it, I still used the same oil I did when it was relatively new. Didn’t do anything different.

@circuitsmith - The recommended oil weight by book is 5W-30 or 10W-30 when the temprature goes below 20 F. I topped up with 5W-30 after checking with the local mechanic last friday.

Then it’s a typo. As @circuitsmith noted, 10W-30 would be for warmer weather, 5W-30 would be for colder weather.

@texases, @circuitsmith, @Bing - Thats correct. 5W-30 is preferred for all season and 10W-30 for hot weather. Here I have attached the screenshot of the manual page.

OK, now it makes sense. Just use 5W-30, you’re fine year round.

Thanks texases!

Your oil consumption is due to age (mileage) and is normal for a car with 190K miles on it…Nothing lasts forever, especially car engines…Not to worry! Just check it now and then and keep it topped up!

“Acts like a 5 weight oil for the winter (thin) and acts like a 30 weight oil (thick) in the summer.” ---- Not exactly. It means it acts as a 5 weight “at start-up” and a 30 weight at 212 deg F, which is much hotter than summer anywhere in the world. The W stands for winter, true, but that doesn’t mean the second number is for summer. Start-up for me this afternoon will be over 90 deg F but it will still function as 5 until it gets hot enough for the thickening molecules to unravel and stretch out, then it will function as heavier oils as it gets warmer, hitting 30 weight at 212 deg F. Keep in mind that 30 weight at 212 is much thinner than 5 weight at start-up. The 30 doesn’t mean it will act like a start-up 30 weight at 212, but like a 212 30-weight at 212.

5w-30 is actually 5 weight oil that has additives (polymers) that when hot make the oil act like 30 weight. The polymers in the oil are coiled up when cold. As the oil gets hot…the uncoil thus making the oil act like a 30 weight oil.

The difference of 25 is about the biggest limit you want to achieve. To achieve 10w-40 with conventional oil you need to start with 10 weight oil…and then add MORE polymers to make it act like 40 weight. The more polymers you have…the LESS oil you have.

Synthetic oil is a little different. You need less polymers to achieve the same results.

@fatrap - A question? I understood that 5W-30, in which 5 weight used for start up and 30 weight at 212 F. My question is at what point (weight) the oil burns in aged motors? Some used to recommend to change oil to thicker whenever the motor starts burning oil. For now I got into action of checking oil (5W-30 - which I have now) more often, NOT changing to heavier oil. What would you recommend? whether to upgrade to heavier oil or keep doing what I am doing now?

My question is at what point (weight) the oil burns in aged motors?

There isn’t just ONE number. It’ll be different for each vehicle and age.

If your vehicle is burning a little oil…adding a thicker oil may NOT be a valid solution. Some engines are NOT designed for a thicker oil. The oil molecules may be too big to pass through some of the oil journals.

I recommend keep using the oil you’ve been using 5w-30. I’ve owned two vehicle with well past 400k miles using nothing but 5w-30.

@MikeInNH - Thank you!

The ‘use a thicker oil’ tactic is kind of a last-ditch effort, right before either the engine’s replaced or the car is junked. But that’s when you’re using a quart every 500 miles (or worse). Don’t do it now, you’ll probably never get to that point, anyway.

Sometimes, a thicker oil makes things worse. I remember a friend who always used STP at each oil change with thickened the oil. His car started using oil at a very young age.
I was riding back to campus with an upperclassman in a 1950 Pontiac. The engine suddenly developed a terrible knock–a rod bearing was going out. We were 25 miles from campus and pulled into a service station. The attendant drained the oil and put in 90 weight gear lube. We managed to push start the car and made it back to campus. The next day a wrecker hauled the Pontiac away to the graveyard for dead cars.

I have written in the past that here in rural Mexico people actually believe that good cars need 20W-50. Some stores don’t even sell anything else.

Once I was looking for 10W-30 Quaker State. I went into a small auto shop, and when I looked at a bottle of 10W-30, the kid at the desk snarled at me, “That will destroy your motor.”

Moron!

I have no idea how this stupid idea got started. But, it is firmly established in this culture. I assume it was passed down from generation to generation. Like the 3,000 mile oil change in 2013.

At least the 3000 mile oil change isn’t harmful…

I ran into something similar when in Anchorage. Found out that Hills Brothers coffee was very popular in AK because some enterprising salesman had given away hundreds of cans decades ago, in towns and villages. The preference lives on. At least that’s the story…