SAE Paper on Engine Wear with 20 wt. oil

[aquariuscsm]

I have actually. But how in this circumstance? Who is monitoring a fricking Ford Quick Lane? The guys who run it aren't even paying attention!

It's all on the corporate level. They count literally everything.

 

[Overfill]

Can you tell me how many "CAFE credits" say FMC gets for back spec'ing older vehicles? I mean, really? Does the Guber'mint give Ford a check for filling your 1999 Crovwn Vic with 5W-20 instead of 5W-30? okaY.. I agree that might not be optimal and my first choice, but I think it's a bit silly to relegate everything to CAFE...

I would think that Ford runs statistics on the likely success of the old engines using 20 weights, and compares it against their risk of costs--including reputation. They put this against the credits given to them in the retroactive re-grading. I can't see this being very risky.. worst thing might be abnormal ring wear..
"Everything"? Sure, but its not that silly to relegate this topic to CAFE.
I trust HPL's 20 weights. But not API blends.

 

[Slow Car Sport Mode]

But what if you are driving a vehicle that was built prior to these "improvements" ?? Like 1998 that was "backspeced " too 5w20?

What vehicle?

 

[Newcmr]

the vehicles are getting older despite thinner oils why is it that vehicles are getting older? better engines? better oils?

 

[ka9mnx]

the vehicles are getting older despite thinner oils why is it that vehicles are getting older? better engines? better oils?

Both. Better engineering and much better lubricants. Rust kills more vehicles than mechanical problems and rust understanding and prevention has improved longevity.

 

[Jpc1623]

Cars are getting more expensive

 

[kschachn]

Yes,

the gas turbine world is my world.

A funny story I’ve told a few times here. During Mobil 254 HTS (high thermal stability) testing, we had a large quantity of lightly used turbine engine oil. Danny (our shop helper) used it exclusively in his 2.8L Camaro. It was not quiet, but it worked and as far as I know there were no failures. It’s easy to dismiss this, but he was rough on his car and beat the snot out of it. Racing everyone.

That guy must have taken home a few hundred gallons of the stuff.

Well likewise I worked in the power generation industry for eight years or so both during college and afterwards, and have also spent the last 30 years in an aircraft maintenance environment. First for a 121 carrier and now with a 135 cargo carrier.

Yes those oils have a high thermal stability and anti-coking properties but they have no ZDDP, little to no detergents, no dispersants and they can cause excessive seal swelling. All of which make turbine engine oils unsuitable for automobile engines. It is good your buddy had no failure when he "beat the snot out of it", but that is not an indication that the oils were optimal nor even suitable for general automotive use. Would you use automobile motor oils in those turbines you work with? Of course not since they are unsuitable. The reverse is true for turbine oils in automobiles.

I know you've been involved in discussions in the past about this and here you are agreeing that turbine oils are not suitable for other applications. It's a fallacy that an oil suitable for a 60,000 HP geared gas turbine is somehow superior to or suitable for an application that is wholly unlike that environment. Kind of like "the military uses it" or "it was developed for the space shuttle" or "it works great in Nascar engines", just because there are big he-man horsepower numbers doesn't make it better. A little 60-horsepower, 8.5 compression ratio ICE with improperly designed bearings will self-destruct just as fast as some dood's monster truck (or geared gas turbine) if there are design inadequacies or improper lubrication. Turbines and their associated gearboxes have nearly zero design similarities to an ICE and the operating environment (and oil conditions) are entirely different.

Are you using turbine oil in your cars? If not, why not? Do you recommend to your neighbors and friends that they use them? They may be good enough to not cause immediate or short-term failure but that in no way deems them suitable.

https://bobistheoilguy.com/forums/t...combustian-engines.273263/page-2#post-4524537
https://bobistheoilguy.com/forums/t...combustian-engines.273263/page-2#post-4523107
https://bobistheoilguy.com/forums/threads/royco-or-aeroshell-555-turbine-oil.327254/#post-5435801
https://bobistheoilguy.com/forums/t...combustian-engines.273263/page-2#post-4524849

 

[kschachn]

As is a lack of basic automotive engine build knowledge. As in modern engines have things like oil coolers that may actually necessitate a (slightly) thinner oil to be optimal. There really isn't that much difference between a given 5W-20 or 5W-30. One relies more on polymers, one might have a thicker base oil to begin with. Guess which is which....

As you've effectively demonstrated it comes down to adequate MOFT. Yes a typical 20-grade oil provides sufficient film thickness for most engines under most operating conditions. Optimal for optimum fuel economy but there is no such thing as optimal for wear. Wear is reduced or controlled but there is never an optimal viscosity in that regard.

 

[buster]

3 good sources in first post. (Shell one I was looking for).

https://bobistheoilguy.com/forums/threads/effect-of-oil-viscosity-on-oil-film-thickness.287003/

 

[CarbonSteel]

If there were no opinion or emotion at play on this forum, then there would be no forum, because we would all just be buying by-the-spec Supertech and be done with it.

Based upon my 12 years here:

 

[Gokhan]

Before the switch to 20 wt oil there was a paper (pretty sure by SAE) that described shorter engine life of 20 wt as compared to 30 wt oil.

As I call the requirement was that the engine would last 200K miles. I recall that number got reduced to 150K miles. Wish I could resurect that information. It was around 2010.

There is no such study. All the longest-lasting engines run SAE 0W-20 or SAE 0W-16, and none of them are thick-Euro-oil-running European engines.

https://www.iseecars.com/car-lifespan-study

 

[Jackson_Slugger]

As you've effectively demonstrated it comes down to adequate MOFT. Yes a typical 20-grade oil provides sufficient film thickness for most engines under most operating conditions. Optimal for optimum fuel economy but there is no such thing as optimal for wear. Wear is reduced or controlled but there is never an optimal viscosity in that regard.

I would never advocate putting a XW-20 oil in everything and as we've seen it may be inadequate in Ford turbos that Ford thought maybe were cooled better than they actually were in real life. But conversely if a vehicle has an oil cooler that is very effective in natural aspiration, perhaps could some XW-30 oils not get to the optimal op temp for additive deployment?

 

[Jackson_Slugger]

I would think that Ford runs statistics on the likely success of the old engines using 20 weights, and compares it against their risk of costs--including reputation. They put this against the credits given to them in the retroactive re-grading. I can't see this being very risky.. worst thing might be abnormal ring wear..
"Everything"? Sure, but its not that silly to relegate this topic to CAFE.
I trust HPL's 20 weights. But not API blends.

Okay, I do trust SAE and I've tended towards FMC in the last few cars and both my parents have older models going on 100K running mostly SAE 5W-20 blends although I now use full syn for the most part. Neither burns any real amount of oil and the only issue is the leaky seals my father's 06 Taurus had, but that seems to no longer be the case after using Oil Saver.

My current Lincoln MKZ has 140K on the 3.7L NA engine, as best I can tell it has had dealer changes with MC 5W-20 and seems to use little if any oil, though honestly the jury will be out for a bit on that as I've only put about 1000 miles on it..

 

[AEHaas]

This weekend we drove the Black Label Lincoln EWB Navigator, loaded, from Sarasota to Miami for a drop off. I-75 was in a rush. The right, slow lane, ran at about 75 MPH, the middle lane at 80 - 85 and the left, fast lane, well, faster. I managed to average 19 MPG. The return trip was different. First we went north to Jupiter, then over to the big lake. 'West from there back to Sarasota at 60-65 MPH with an average of 22 MPG. The 0W-5 oil has not blown up the engine as yet.

ali

 

[Al]

Basic engineering has not changed since I had a design course in 1968. And back in the day there was a "term" called Bearing Caracteristic number. Where v=viscosity, L=bearing load, and N = speed. The term is.. vN/L. Relatively, the smaller the number the more wear. Given two specific bearings:

1. No design change but changing viscosity of the oil from 30 wt to 20wt. Doesn't take a rocket scientist to understand why "in the beginning" SAE/API knew engines would not live as long with 20 wt oil. Solution: lower the load (increase bearing area). Wala-problem solved.

2. Using 30 wt in engines designed for 20 wt. Bearings are forgiving with respect to viscosity. Viscosity can run between 5 and 5,000 cSt. (if speeds are not outrageous). So it follows that increase in viscosity raises the bearing number and reduces wear. So what? The bearings will be OK for the "life" of your vehicle. And I am just anal..lol.

But science in some areas is frowned on-on this board. Hope this doesn't upset anyone.

By the way thats why turbines need lower viscosity oil. I didn't need turbines to be my life..lol

 

[oilcandave]

There was a tv commercial i think it was for synthetic castrol many years ago. They had 2 similar motors...one with dyno and the other synthetic. They ran them up to temp..drained the oil and restarted the motors to see which one ran longer without oil.

Would like to see a similar test using 20wt and 40wt and see which one runs longer before they set up...just for fun.

 

[kschachn]

There was a tv commercial i think it was for synthetic castrol many years ago. They had 2 similar motors...one with dyno and the other synthetic. They ran them up to temp..drained the oil and restarted the motors to see which one ran longer without oil.

Would like to see a similar test using 20wt and 40wt and see which one runs longer before they set up...just for fun.

It would make little to no difference. And on that commercial, are you sure the engines were under load? All of the “engine running without oil” commercials I’ve seen are unloaded engines. It is little more than a parlor trick.

 

[SubieRubyRoo]

It would make little to no difference. And on that commercial, are you sure the engines were under load? All of the “engine running without oil” commercials I’ve seen are unloaded engines. It is little more than a parlor trick.

Slick 50, anyone?

 

[flyer69]

Slick 50, anyone?

Hey now, I ran Slick 50 for one oil change back in the day. The engine didn’t blow up. Thus, Slick 50 is the best thing ever. 1000% success!

 

[Jpc1623]

Ran Slick 50 in a Saab 900 I got 359000 miles. That’s when the odo broke. Had to donate the car…, RUST