Thicker oil civilization is taking over

[turnbowm]

Originally Posted by 69Torino
... knowing what I've seen and been through, I believe a good Synthetic 5w-30 is the elixir on these engines. Hope this helps a little.

Thanks much for your reply and sharing your vast Kia knowledge. I'm been using PUP and, most recently, PP D1G2 synthetic 5W30 since I started doing my own servicing at 15,000 miles.

What are your thoughts on using an A3/B4 or Dexos2 5W30 synthetic with HTHS = 3.5 for added protection in these engines?

 

[turnbowm]

Thread bump.

 

[hatt]

Originally Posted by OVERKILL
Originally Posted by Cujet

It's also incorrect to think engines designed for 0W-16 will have wider bearings. A far more appropriate course of action is to reduce reciprocating mass. The greatest bearing loads are due to RPM and inertia. Unless the engine has 33 pounds of boost, then con rod bearing loads can exceed inertial loads.

Designs won't change much, if at all.


Honda's design for 0w-16 included wider bearings, Shannow has covered this in the past:

Originally Posted by Shannow
Yeah, if you look in interesting articles, there's a heap of stuff, including from Honda where they are testing lower.

Invariably, when looking lower, they are redesigning engines with greater bearing swept surface areas and lower radial clearances to make these new lubes work...not backspeccing on existing designs.


Originally Posted by Cujet
What will happen is that excessive oil temperatures will be managed more carefully.


Which is already happening on engines running xW-20 with the thermal castration mechanisms now in use.

Originally Posted by Cujet
Off topic a bit. Aircraft engines, such as the 111,000 HP GE-90 use very thin oils. Interestingly, the GE-90 has better HP to weight than modern Formula 1 engines. The design AND management of the engine is key.


Yes, jet engines have always used very thin oils, the operation of a turbine isn't really comparable to that of a piston engine, since there are no reciprocating components.

Wouldn't wider bearings do the exact opposite thing you're trying to do with <20 grade oils?

 

[Shannow]

Originally Posted by hatt
Wouldn't wider bearings do the exact opposite thing you're trying to do with div>


Yes, but I've covered this in the past.

Honda papers indicate that they are chasing piston and skirt friction. Also that they are changing bearing dimensions, and stiffening the lower end of blocks. So the efficiencies that they are getting with the piston friction reduction must be greater than the losses with the bottom end...it's an optimisation process, with a sweet spot somewhere in the middle. Compare the bottom end of a small block chev or ford, or traditional straight 6 with a modern deep skirt, cross bolted offering...stiffer block, better alignment, smaller clearances possible.

Other heavy duty engine manufacturers for big diesels are doing the same sort of optimisation by thermal barrier coatings on the water jacket mid stroke to keep the viscosity lower mid stroke (less piston friction), without dropping viscosity and messing with bearing sizes.

 

[Shannow]

Re reducing reciprocating mass...

Consider that the modern engines rev harder, have far higher cylinder pressures, and are now getting into reduced margin before abnormal ignition events...I can't see much in the way of mass reduction in the reciprocating assembly.

 

[bbhero]

Originally Posted by Garak
Originally Posted by Shannow
When I first found the thread I wanted to post an Offspring song as a video refutation LOL (Come out and play...good song)

Yah gotta keep 'em separated.



Two great posts here. From two of my favorite guys on here... Well done : )

 

[BrocLuno]

Wider bearings are the only way to make up for viscosity loss and reasonable life expectancy. You need area to support a thinner film. Only two ways to get there. More diameter, or wider bearing. Making cranks bigger is counter productive, so wider it is.

 

[CourierDriver]

If we could design an axial flow small jet engine and reduce heat exhaust, you would have one rotating mass and maybe just 2 bearing loads, but most likely it will not happen in our lifetime, it has been done on the race car circut many year ago though..

 

[fdcg27]

As I've always posted here, any engine will run for a very long time on a variety of grades.
You are correct in identifying the trade-off between fuel economy and engine life.
As you've posted in the past, this isn't a matter of engines wearing out at low mileages using thinner grades.
It's rather a matter of how much life is left in the engine when the vehicle in which it's installed takes its last ride to the yard.
Since I know from personal experience over the years that ~200K or fifteen years is the practical life of a vehicle in this neck of the woods, I'm not overly concerned with the incremental wear that a 0W-20 must bring. For the record of the three cars I've actually seen record more than 200K in my possession, one was an old Benz 123 diesel and two were Hondas. The Benz always got thick oils and the older Honda did as well while the later one usually got nothing thicker than thirty grade. The old diesel Mercedes and the newer Honda, a '97 Accord 5 spd were sold on as running drivers while the older Honda, an '86 Civic Wagon 5 spd I think swallowed a valve. Oil grade had little or nothing to do with the lifespans of these cars.
If I lived in the Arizona desert or SoCal, I might think differently, or maybe not.
After 200K and maybe eight or ten years, I'd be ready for something different anyway and the buyer of the running and driving fully functional car that I dispose of won't ask whether I ran a twenty, thirty or forty grade oil.

 

[spasm3]

Originally Posted by Garak
Originally Posted by Shannow
When I first found the thread I wanted to post an Offspring song as a video refutation LOL (Come out and play...good song)

Yah gotta keep 'em separated.



Hilarious, i could see castrol using that song in a motor oil ad!

 

[Garak]

It's probably not a bad idea.

 

[OilUzer]

Originally Posted by fdcg27
As I've always posted here, any engine will run for a very long time on a variety of grades.
You are correct in identifying the trade-off between fuel economy and engine life.
As you've posted in the past, this isn't a matter of engines wearing out at low mileages using thinner grades.
It's rather a matter of how much life is left in the engine when the vehicle in which it's installed takes its last ride to the yard.
Since I know from personal experience over the years that ~200K or fifteen years is the practical life of a vehicle in this neck of the woods, I'm not overly concerned with the incremental wear that a 0W-20 must bring. For the record of the three cars I've actually seen record more than 200K in my possession, one was an old Benz 123 diesel and two were Hondas. The Benz always got thick oils and the older Honda did as well while the later one usually got nothing thicker than thirty grade. The old diesel Mercedes and the newer Honda, a '97 Accord 5 spd were sold on as running drivers while the older Honda, an '86 Civic Wagon 5 spd I think swallowed a valve. Oil grade had little or nothing to do with the lifespans of these cars.
If I lived in the Arizona desert or SoCal, I might think differently, or maybe not.
After 200K and maybe eight or ten years, I'd be ready for something different anyway and the buyer of the running and driving fully functional car that I dispose of won't ask whether I ran a twenty, thirty or forty grade oil.


I like it

all your cars lasting more than 200K miles, got thick oil ... But you also mentioned that "Oil grade had little or nothing to do with the lifespans of these cars."
There is no need to assimilate you but we'll work on your modesty

j/k

 

[nap]

I keep hearing that all those cars populating the junk yards have perfectly working engines, up to factory specs, and that the reason for which they are there is obsolescence or rust. Is there any evidence to support this theory?

 

[bbhero]

Originally Posted by spasm3
Originally Posted by Garak
Originally Posted by Shannow
When I first found the thread I wanted to post an Offspring song as a video refutation LOL (Come out and play...good song)

Yah gotta keep 'em separated.



Hilarious, i could see castrol using that song in a motor oil ad!



You really need to contact Castrol with this idea for an ad campaign... A hit for sure

 

[NGRhodes]

Then there's the progressive bohemian school of thinking that even 0W oils are relatively thick towards the cold end...

 

[Red91]

I've always just tailored oil choice to an individual vehicle and it's intended use, consumption and oci. My 89 Chevy truck with a 305 gets 20/50 because it leaks some oil, burns some oil, and at any given time could be idling in the dog days of summer and hauling max payload up and down hills. Plus it's a thirty year old 305. It's a beater that im not going to sink much money into. It used two quarts of 20/50 in the last 3500 mile/4 month oci.

My 15 cruze gets conventional 5/30 because the girl who's buying it wants it serviced every3000 miles. It's 1.8 four banger is port injected with a timing belt(unlike the 1.4 it could have had, which is turbod, di with a chain) so a dexos syn 5/30 is just spending more money and a waste of oil.

The other dexos apps I service personally are all di/ and/or turbod and do fine on plain dexos synthetic 0/20 and 5/30 per the olm.

These are just a few examples. The whole thick vs thin and syn vs conventional debate is just another reason for people to argue on the internet. I'll worry about the 0/16 issue when the time comes that I service one personally, just like I did with dexos.

 

[userfriendly]

Don't worry about 0W16, it likely has a thicker base oil viscosity than 0W20, or 0W40 for that matter.
Back in the day, SAE 10 (W) was the go-to winter grade and severely gasoline diluted come spring.
A modern group II SAE 10, well could pass in the dark as a 5W16. Maybe not in the cold crank, but a 5W pump n flow.
If the engine starts, the oil better pump n flow.

 

[burla]

Identify the trade off and proceed, but there is a lot of manure in the minutia of this issue thanks to our gov't.

They force Ram to have a mds system for fuel standards, but the system closes off 4 cylinders and sends more fuel to the other 4 cylinders, lol. Does this save fuel in real life? No, only in a lab. And, they spec 5w20 for these 400hp engines. But the cost has been horrible with cam/lifter issues with hemi's, many failures of this item have been noted on the boards. Let me ask another question, does this fact bother the gov't? or even the manufacturer? [censored] no it doesn't, by the time the cam/lifters go out usually about 70-100k miles there is so little value left in the truck it is barely worth paying the huge cost of that item. 9 times outta ten the guy buys a new truck, winner winner chicken dinner for the gov't who makes huge tax on vehicles and the manufacturer as well. And seeing that the entire industry is on board, you can't avoid it, a similar dish is forced on you with other truck brands as well.

Now, same thing with the Ram eco diesel, low weight spec oil but this time the numbers were so horrific on bearings failures they had no choice but to change the spec oil and go up in weight.

Viscosity obviously dependent on temperature, so if you are trying to sell me on the fact the tolerances are so tight that the operating viscosity of 12 is going to have bad consequences on a vehicle that specs an operating viscosity of 9, I aint buying that. IMO, the trade off is potential fuel economy versus potential metal protection. If you want to know for sure, try either in your vehicle, there are easy ways to test for both. UOA will show you if the wear numbers are different, gas mileage is even easier to figure out. The rest is just a bunch of who shot john.

 

[OVERKILL]

Originally Posted by burla
Does this save fuel in real life? No, only in a lab.


It saves fuel in real life. The gas mileage difference between an MDS HEMI and non is readily verifiable. I put my Jeep in "sport" to disable the MDS, my mileage goes down, even driving the same road at the same speed in the same gear.

Originally Posted by burla
And, they spec 5w20 for these 400hp engines. But the cost has been horrible with cam/lifter issues with hemi's, many failures of this item have been noted on the boards. Let me ask another question, does this fact bother the gov't? or even the manufacturer? [censored] no it doesn't,


Yet the spec is for 0w-40 in the 6.4L with MDS and they have not experienced the lifter failures, despite using the same part #'s....

Originally Posted by burla
Now, same thing with the Ram eco diesel, low weight spec oil but this time the numbers were so horrific on bearings failures they had no choice but to change the spec oil and go up in weight.
The 5w-30 spec'd for the EcoDiesel wasn't "low weight". It was a C3 oil, which requires a minimum HTHS of 3.5cP.

The oil spec wasn't the only thing that was changed, either. 2016+ received updated PCM programming that prevented the engine from being lugged in addition to the transition to a 5w-40 viscosity.

 

[gfh77665]

Originally Posted by Rolla07
I choose to not be part of either camp but it seems the thick crowd is more upset about thin oils than the thin crowd is upset at thick oil. Its a personal preference, so to say x is better than y is strictly opinion and not fact. Unless you can prove it.


"Upset" is disingenuous. I doubt any thick advocate is really "upset". I do think many take exception to CAFE being rammed down our throats. I do think many read through the MFG. (CAFE) recommendations and pick up on wording like thin oils provide "adequate" protection. I do think there are concerns 0w-8 or whatever is the next step.