Up oil weight with high mile engines?

[george1122]

OK. I'm open for suggestions on oil grades. 13' CRV AWD K24 engine / original owner/ 0W20 it's whole life / 614, 877K on the ODO. I maintain it. I'm in New York. Avg temps 20-90 degrees. 3k OCI's . Daily driver.. What is the preferred grade at that mileage ?????? And yes, it starting to get a bit clackity clack when hot/ warmed up. Had valves adjusted 3X already. I'm thinking the clackity clack are worn bearings. No piston raps, or crank shutter. Idles beautiful.

Consider 0W30 or 5W30. I'm surprised the manual calls for 0W20 rather than 5W20. NY isn't quite the arctic.

 

[altaylar]

Are you sure it is better to run thicker oil at 260f rather than the manufacturer's suggested weight at 210f? IOW, is it worth the increase in temperature?

I don't think you understood the situation there. Its is not either or question. It is choosing the right viscosity for the given temperature. Single degree of freedom on the equation. When you track your car, or tow a trailer, your oil does get warmer

 

[george1122]

Sometimes people inadvertently create the very problem they're trying to prevent. Arbitrarily increasing viscosity due to high mileage is a prime example of this. When you go up in viscosity, two things happen. Flow decreases (slightly, more strain a PD pump to move the same volume) and hydrodynamic friction increases. Speaking of the bearings in particular, both factors increase oil temperature rise through the bearing and thus increase bearing temperature, increasing bearing fatigue. (however slight it may be) As for the oil itself, higher viscosity often means a lower heat transfer coefficient so the oil is less capable of removing the extra heat. (again, however slight the difference may be)

If you want to protect an older engine, you want a better quality oil, not a higher viscosity one. You want an oil that cleans well, shears less, keeps old seals pliable, is less volatile, and is more resistant to acidic growth. Ideally, you run such an oil from day 1.

Interesting post.

What is an example of a low quality oil and high quality oil referred to in your post?

I'm under the impression conventional oil cleans better and keeps seals more pliable than synthetic oil. OTOH, synthetic shears less. Not sure if I'm right, though.

 

[altaylar]

Interesting post.

What is an example of a low quality oil and high quality oil referred to in your post?

I'm under the impression conventional oil cleans better and keeps seals more pliable than synthetic oil. OTOH, synthetic shears less. Not sure if I'm right, though.

Does not seem too accurate. Synthetic often regarded as a better cleaning one (especially some group 5). For seals, i dont think there is a major difference, except some classic car's seals are not too compatible with synthetics. Of course there are exceptions (like pao).

 

[Carlostrece]

There are various weights of oil, of course. Is there an amount of miles on a vehicle where it is a good idea to jump up a weight in oil?

In other words, is there a certain amount of miles where to get the same function from the weight a person was using, that person needs to go up in weight?

Miles no. Condition, sometimes yes.

If it's leaking or burning oil, I'd consider going up 1 grade, but first I'd try HM oil if leaking oil, or VRP if burning oil. If those don't fix it within 2 oil changes, then I'd consider going up 1 grade and continuing to use HM oil or VRP in that thicker grade. Others may disagree.

Replacing leaking seals or gaskets is the best option for oil leakers if HM oil doesn't fix a minor leak. Sometimes HM oil can fix a minor leak, but it won't be able to fix a serious leak. Same with thicker viscosity oil in regard to leaks.

However, a HM oil that is also 1 grade thicker viscosity will stop minor leaks and slow serious leaks, IME. i.e. - combining the 2 is a powerful combination, IMO.

As for reducing oil burning, I touched on that in this post and others. Also, many other people have addressed it.

As with anything... The above is my opinion based on my experiences and research. Others may agree or disagree.

 

[Astro_Guy]

Did the owners manual say you could use 15W50? I'm surprised you didn't try 10W40 first.

No - it did not. My intent here was to warn the "thickies" out there from going too far as I did.

Next up for me is a change on the 2023 Prius using 0-w16. I guess I've overcome the "thickie" thing.

 

[RDY4WAR]

Interesting post.

What is an example of a low quality oil and high quality oil referred to in your post?

I'm under the impression conventional oil cleans better and keeps seals more pliable than synthetic oil. OTOH, synthetic shears less. Not sure if I'm right, though.

Under the API umbrella, conventional oil does not clean any better or worse than synthetic oil. That's a general statement. There's exceptions such as Valvoline Restore & Protect. The same applies to seal conditioning. Conventional will typically contribute more deposits and varnish due to higher volatility and weaker oxidation resistance.

There was an issue observed over 50 years ago that a specific synthetic base oil (group IV PAO) caused elastomer seals to shrink. This was easily remedied by adding group V ester to condition the seals and improve solubility. The issue disappeared. PAO isn't even used in large amounts in any API oil these days and hasn't been for 20+ years. Oils that contain high amounts of PAO are in the boutique realm (Amsoil, HPL, Driven, Red Line, etc...) who also use high amounts of ester, and most perform better than common API oils when it comes to seal pliability (and pretty much every other parameter).

As for a low quality oil vs a high quality one, here's an example in D892 foam testing. Rotella produced >2.5x the limit for CK-4. HPL had practically none.

This engine had 200k miles on it at the time of this picture. It's had the HPL HDMO 5W-40 above since new. When you use a good oil that runs clean, high mileage isn't a concern.

 

[STMech]

That's good classic info that's still relevant. I figured out the same in the 80s.

You were in autoshop in 1969?! That was a while ago!

In High School, I was 17. That year I competed in the Plymouth Troubleshooting Contest. Ancient history now.

 

[50yr Street Mech]

Wow.....that was a lot of threads. !!! Thanks everybody It's not the timing components making the clackity clack, very subtle noise. Just sounds like the engine is tired and loosey goosey. That's why I'm leaning towards bearings,,,,like all of them..just worn down a bit. So, I did read a thread to consider 0W30 or 5W30. In the expertise,,, of this forum, which should I pick ?????

 

[Hohn]

0w-30, of those two. M1 ESP, in particular. HPL would be the upgrade choice.

 

[50yr Street Mech]

Now, tell a novice what M1 ESP HPL means....please ????? I'm not up on this fancy lingo yet.....workin on it

 

[Hohn]

To respond the question of higher viscosity in higher mileage engines:

You can’t really band-aid something wrong with thicker oil. If your bearing clearance is huge because they are worn drastically, the even 20w50 won’t fix that. Yes, you’ll have better oil pressure but you’ll still have very short life left because the roached surface finish of a bearing that badly worn would need more than a couple points more cSt to establish full hydrodynamic lube.

If an engine has made it to high mileage with little to no consumption, why not stick with that?

That’s kind of the catch-22 with going thicker on oil just because the engine is old. Either its old and in great shape, which suggest going thicker is unnecessary. Or it’s old and in rough shape, which cannot be helped by thicker oil.

If the bearings are roached, the time to go to thicker oil was years ago.

 

[george1122]

@RDY4WAR :

Thanks.

That engine looks like new.

 

[Hohn]

Now, tell a novice what M1 ESP HPL means....please ?????

Mobil 1 ESP 0w-30. ESP is their Emissions System Protection line (mid-SAPS oils).

HPL is High Performance Lubricants, considered by many knowledgeable people to be the best oils you can buy at any price.

 

[Hohn]

@RDY4WAR :

Thanks.

That engine looks like new.

It does, but don’t be too impressed about the cleanliness of a loafing V8 in a motorcycle when it spends its life at low load with valve covers and heads getting blasted with cooling air.

If this was the engine in grandma’s old station wagon, that’s another matter. This particular application (if I have it correct) is VERY easy on the engine.

 

[AEHaas]

Those parameters are how OEM engineers decide the appropriate grade. It's based on HTHS but presented as a grade since it's more publicly familiar. The worst case scenario is factored in that decision.

Also note that I said most engines would see no benefit, not all. As with anything else in life, there are exceptions to the rule.

If you're really concerned about high mileage, look for a better quality oil, not a higher viscosity one.

That last line says it, same for better engine wear protection and resistance to oxidation and other things.

Oil viscosity is not a “weight”. That’s something that is misunderstood by many people, including on here. They are grades.
So the proper term would be to say 30 grade, not 30 weight.

That has bugged me for years, actually decades. I cringe every time I see "weight" used where Grade is what is being discussed. Is there any way to get people here to use the proper term? My blood pressure is high enough already.

Ali

 

[50yr Street Mech]

Thank you : ) The bearings aren't roached yet. Very subtle noise. Now I know what to buy. Thanks Guys

 

[Carlostrece]

That last line says it, same for better engine wear protection and resistance to oxidation and other things.

That has bugged me for years, actually decades. I cringe every time I see "weight" used where Grade is what is being discussed. Is there any way to get people here to use the proper term? My blood pressure is high enough already.

You're correct about grade being the correct term, but does it really matter? We all know what he meant. BITOG is the only place I ever heard people correct others over it.

 

[altaylar]

You're correct about grade being the correct term, but does it really matter? We all know what he meant. BITOG is the only place I ever heard people correct others over it.

I also think this is a BITOG thing, and not sure why people are that sensitive about it. My friends working in auto industry as engineers call it weight, marketing people in the oil industry often calls it weight. They even dislike calling it grade as there is a grade for many other things in a car as well as in an oil, whereas the word weight feels more speaific.

 

[Dborch41]

In Auto Shop class back in 1969, the instructor told us that 30 weight oil was for engines in good condition. Spec bearing clearance back then was about .003 inch. A worn engine with .004 clearance needed 40 weight. If your Chevy was blowing blue smoke, you probably had loose rods at .005, and 50 weight was your last gasp. He was a good teacher, and there's some truth to his tale, even today. Just look at GM.

About a hundred years ago I was a wide-eyed student in A&P school (airplane mechanic for the uninitiated). My favorite class was with the test cells where there was a variety of operational engines we got to play with. My favorite was an old R-985 9-cylinder radial, it ran great but was pretty worn out. The clearances had gotten so loose we had to run what was essentially gear oil in the tank, but even with that it still farted about a pint out of the stack every time it started up.

Regardless that thing could still pull about 35 inches of manifold pressure courtesy of an integral supercharger. The sound of that little beast at full tilt was something to behold.