Using 5w-20 in place of 5w-30

[leftlane]

Originally Posted By: FZ1
It's stupid not to let the dealer do all work during the warranty period for documentation.


The dealer mechanics sure can be stupid which is why I change the oil myself that way I know its done right. Dealers in the past have filled one of my vehicles up with the wrong oil grade once, overfilled the oil almost a half inch above the full mark several times even after I told them to stop doing it, changed the oil without my consent once at only 500 miles since the last oci, overfilled the transmission fluid almost a half inch above the full mark once, and over tightened the oil filter and drain plug once despite my asking them not to. They have also tried to get me to replace my pads telling me they were almost completely worn when I later found out they had 70% life left. I just asked one about the price of oem o2 sensors and they want $146 each when I can find the same sensor at rockauto.com for around $60. All of this is nothing new and they constantly try to get you to buy overpriced parts and service that are not even close to being needed so I dont trust dealers at all in general. The more you go them the more youre asking for problems so if you can do maintenance and repairs yourself you'd be much better off.

 

[RedOak]

Did not mean to get anybody fired up. Thinking out of the box is good for everybody. Each has his or her views on what works. I feel 5w-20 semi or full synthetic are excellent values. They hold their viscosity better than previous SL oil and better than most sm oils. Better base oil and usually higher tbn.

 

[Audi Junkie]

Air ~is~ a lubricant.

 

[RedOak]

Sure compress some at put in your crakcase.

 

[1sttruck]

"That is, just because you state that the lighter viscosity oil is easier to breach than a heavier weight ...just what mandates that it will ever see condition (other than initial startup) that it ever sees enough stress to do so?? "

As with any vehicle/engine, even one 'designed' for 5w20 (one really designed for it, not just used to to meet fleet CAFE requirements), conditions of high enough temperatures, lugging (typically with a manual tranny), loads on grades with high temps, etc., can push an engine to limits, and the oil too. Looking at the previous post part of it explains why engines like diesels need thicker oils, as they have high compression, low rpm, in trucks are designed for heavy loads, and can generate some high temps. These things require a thicker oil, while a lower compression, higher revving engine designed for lighter loads can get by with thinner oils. In every case one typically ends up trading off wear at different points in an engine with the lower friction offered by thinner oils, for performance, cold start ability, and/or fuel economy. For most people the 'loss function' of excessive wear has a shallow slope, where better or worse will typcially only be seen over long intervals. In some cases though it can get steep if a thin oil is used in an engine that isn't really designed for it.

I have the impression that thin oil advocates want some reassurance from each other that they've made the one true choice, and that there are no tradeoffs whatsoever. Well, there are always tradeoffs, that's how engines and oil work. You've made a choice, now be happy. I am :^)




A test using Lubrizol and Castrol oils. Wear isn't measured.

http://me.engin.umich.edu/autolab/Publications/Adobe/P2008_01.PDF

Effects of oil properties on spark-ignition gasoline engine friction

1.3. Effect of viscosity grade
Viscosity is a fundamental property of engine oil. If the oil is too thin (i.e., low viscosity), oil film thickness between components is reduced enough to cause asperity contact, resulting in mixed or boundary friction. If the oil is too thick (i.e., high viscosity), hydrodynamic friction coefficient is unnecessarily increased; thick oil also takes longer to pump through the engine following a startup, causing more boundary friction and wear. Optimum viscosity depends on engine design. Engines with minimal boundary friction benefit from relatively thinner oils because lower viscosity reduces the hydrodynamic friction coefficient. These engines are often called ‘‘low friction engines’’ and usually employ roller follower valve trains, carefully designed piston ring/wall characteristics and lubrication systems. Engines with more boundary friction benefit from relatively thicker oils because the reduction in boundary friction more than offsets the increase in hydrodynamic friction coefficient. These engines often utilize sliding contact valve trains and have piston ring/wall characteristics that allow more asperity contact. Optimum viscosity also depends on how the engine is operated. Engines operating under low speed, high load or in hot climates typically require thicker oil.

4. Conclusions

....For a given viscosity grade, synthetic oil reduces engine friction, especially at the high boundary friction point. The reduction may be a result of the synthetic oil requiring less viscosity index improvers, which displace lubricating oil and reduce overall lubricity, or by containing more polar molecules that stick to engine surfaces and reduce boundary friction.

....When oil viscosity grade was varied independently (series #1), viscosity grade had little effect on engine friction, although experimental uncertainty could be concealing a similar trend as found in series #2. Test series #2 showed lower friction with 5W-20 oil as compared to 5w30 and 10W-40 oils at both operating conditions. Series #2 seems to suggest that for this engine design, the benefit of reducing hydrodynamic friction coefficient with thinner oil is more significant than the benefit of reducing boundary friction with thicker oil. However, since additive package and FM are not controlled in series #2, the observed reduction could also be a result of added FMs.





A paper that has been posted numerous times in this forum.

http://www.eng.auburn.edu/~jacksr7/SAE2002013355.pdf

Lubrication, Tribology & Motorsport

Clearly, Table 6 shows that reductions in piston ring friction can be achieved by moving to a lower viscosity lubricant. However, this is at the expense of lower minimum oil film thicknesses. There is a trade-off between reduced friction (and greater power available to the wheels) and engine durability.


Lubricant Minimum OFT (Pm)
SAE-20W/50 4.13
SAE-15W/40 3.72
SAE-10W/30 3.01
SAE-0W/20 2.63
Table 7: Sensitivity of con-rod bearing results to lubricant
viscosity grade at 2500 rpm

 

[RedOak]

Am happy any will deal with it 1sttruck. You make valid points. But I do not have a f-350 power stroke. I have run 5w-20's for years in ford 150's with excellent results.- You just can not push the oci out to 8000 plus like I have seen some fleet vehicles with conventional 5w-20 or 5w30.

 

[Gary Allan]

Quote:
As with any vehicle/engine, even one 'designed' for 5w20 (one really designed for it, not just used to to meet fleet CAFE requirements), conditions of high enough temperatures, lugging (typically with a manual tranny), loads on grades with high temps, etc., can push an engine to limits, and the oil too.


And for how many decades have engines been "designed" to run on 5w30 multivisc oils that sheared to 20 weights? Just because refining and blending has improved at producing 5w30 oil doesn't alter this (proved by no more than BILLIONS of miles of in field testing).

Quote:
Looking at the previous post part of it explains why engines like diesels need thicker oils, as they have high compression, low rpm, in trucks are designed for heavy loads, and can generate some high temps. These things require a thicker oil, while a lower compression, higher revving engine designed for lighter loads can get by with thinner oils


..and if everyone was driving a light to medium duty diesels I could see your point. Since they aren't ..and the vast ...galactic expanse type proportion type of "vast" preponderance of in field usage shows that the use of either designed lighter oils ..or "degraded to lighter oils" has shown no impact in wear related failure or loss of utility.

Again, I think you'll admit that you aren't running scared because you can't find 50+ weight oil for the "added protection". If any was to be had, you would use it - if your school of thought has immutable validity. Yet you would run scared in a passenger car engine that is, by your own admission, more suited to using lighter oils???

Where's the apparent proof in the field?

 

[1sttruck]

"And for how many decades have engines been "designed" to run on 5w30 multivisc oils that sheared to 20 weights?"

These were pretty crummy oils, ones also designed for better fuel economy, which is why I don't trust the OEMs on this issue. We had the 93 Taurus serviced at Ford for quite awhile and ended up with a pretty dark looking engine staring in the oil filler cap, one that also started burning oil not too long after 100k miles. Our 'ultra reliable' 87 Civic was blowing blue smoke at startup at 120k miles, it had low compression, and although the problems weren't all oil relatd the crummy oil also didn't help. So BBBZZZZZZZZZ, with me you lose big time if you suggest that those oils were just fine.

 

[Gary Allan]

Quote:
So BBBZZZZZZZZZ, with me you lose big time if you suggest that those oils were just fine.


Well, as much as I'd like to consider that my realm of experience contours to the rest of the universe; using it as a statistical template.. if you will, I do realize that, as with all things, YMMV.

 

[JAG]

Originally Posted By: Gary Allan
..and I don't even know what the eff I'm talking about ..sheesh.
I wouldn't say that but some diligent self-directed study of engine tribology will help any of us. Getting access to the literature is a big road-block though.

 

[Gary Allan]

Quote:
Getting access to the literature is a big road-block though.


..and getting it in Cliff Notes and

versions at the same time is equally challenging

 

[JAG]

LOL. Would Romper Room versions speak in terms of "slippery" and "sticky" for "coefficient of friction" and "high viscosity", respectively? Detergents would be depicted as little men with shovels? Me thinks so.

BTW, did you know that fish oil has been used in some motor oils to decrease the coefficient of friction? Kind of gross. I wonder if it smelled like heck.

Also, a 0w30 showed better fuel consumption than a 5W-20 oil. It's all in the mix.

 

[JTK]

RedOak, I'm sure you've done some reading on it. Your 4.7L wont know the difference between a 5w30 or a 5w20. Run a 5w20 and take what ever tenth of a percent fuel economy gain it will offer.

Joel

 

[Gary Allan]

Originally Posted By: JAG
LOL. Would Romper Room versions speak in terms of "slippery" and "sticky" for "coefficient of friction" and "high viscosity", respectively? Detergents would be depicted as little men with shovels? Me thinks so.

BTW, did you know that fish oil has been used in some motor oils to decrease the coefficient of friction? Kind of gross. I wonder if it smelled like heck.

Also, a 0w30 showed better fuel consumption than a 5W-20 oil. It's all in the mix.


I recall a late 80's or early 90's released Amsoil publication that showed a list of many oils ..with the notion that Amsoil beat Mobil 1 (which it did). On the same list (in the list of performance results) jojoba bean oil beat both of them

Here's my basic premise here (in terms of viscosity). You have an oil with a HTHS visc of 3.9. I use one with 2.6.

If 2.6 is enough (for the moment we'll assume that it is as a pre-qualification) to keep me outside the boundary layer ..and I never get anywhere near 302/150C anywhere in my engine ..what's the difference in terms of protection between either of them???

This is what I keep missing in 1sttruck's evidential posts. They tend to assume some pre-required "inadequacy" with lighter oils. Sorta like you're trying to make them fail.

Now if you're looking at EVERYTHING from a perpetual WOT or full potential/X-duty usage modality, then you need to refine your view ..but surely qualify it as such.

That is, you can't "infer" wear just due to visc.

 

[PT1]

Ok so what do you guys think of me trying PP5w20 in my YukonXL 6.0L V8?

 

[leftlane]

Originally Posted By: JAG

BTW, did you know that fish oil has been used in some motor oils to decrease the coefficient of friction? Kind of gross. I wonder if it smelled like heck.


Makes me wonder if the bears would tear your car up thinking there's some fish in it.

 

[JAG]

Originally Posted By: Gary Allan
Here's my basic premise here (in terms of viscosity). You have an oil with a HTHS visc of 3.9. I use one with 2.6.

If 2.6 is enough (for the moment we'll assume that it is as a pre-qualification) to keep me outside the boundary layer ..and I never get anywhere near 302/150C anywhere in my engine ..what's the difference in terms of protection between either of them???
If 2.6 cP is enough to provide good wear protection and it gives better gas mileage than the thicker oil, use it.

It often is not so with an oil that thin applied to all common modern gas engines. That oil has it's place though. You can have a hoot tonight if you Google:
" bearing oil temperature HTHS "! You'll find all kinds of fascinating findings if you keep looking at at least several pages of results. Some hits are BITOG threads too. Even though it's Friday, don't mix alcohol and web research.

 

[Gary Allan]

Well, my thought here is that any reasonable oil temp control negates most of the anxiety about HTHS visc. Although there are plenty of hits on the words you suggested, I couldn't get much when using "gasoline engine journal bearing temp". Plenty of references to topography and whatnot (most want $$ to read).

One will assume that monitored oil temp will be an average of higher and lower temp sources, minus some natural or forced rejection rate.

Now if there's any validity to this summary of some paper somewhere our journal bearings add little to the sump temp equation in these tests of 2000rpm WOT and 4000rpm WOT ..where piston crowns added the lion's share of the btu surplus. So (and to attempt to take in a little more of the extended content to the paper), if we're in a stable coolant temp ..we should be in some stable oil temp and well below our HTHS visc.

So, assuming proper design and whatnot ..the vast majority of Honda Civics, Crown Vic's, Chevy Malibu's, Toyota Corrolas, ...and even...non tracked Corvettes

..etc..etc can just loaf along @ 75-95 mph and not really (as in "come on... really now") worry about their HTHS visc, correct??

That is, when one is assertively promoting added protection with higher visc fluids, we're really talking extreme buffering for extreme (and marginal) circumstances, correct?

This would suggest, again if the paper has a reasonable confidence validity level, that anyone who doesn't see a real coolant temp gauge twitch, can ignore HTHS visc all together, right?

That is, while some may push the envelope, most have VERY wide margins on "their envelope" of protection.

 

[1sttruck]

Engines wear out, and how quckly they wear depends upon load, temperature, and suitability of the oil for the load and temperature. As I've stated numerous times 5w20 will work fine for almost everyone in the US, but it doesn't mean that wear isn't related to viscosity; "Figure 3 also compares wear data between oil temperatures of 100°C and 50°C. Wear at 50°C was extremely small due to significant reduction in the severity of contacts due to the increased film thickness resulting from increased oil viscosity. The wear rate under this condition was near zero. However, the wear rate increased when the oil temperature was raised to 100°C again."


http://findarticles.com/p/articles/mi_qa5322/is_200711/ai_n21298415/pg_1

Valvetrain Friction and Wear Performance with Fresh and Used Low Phosphorous Engine Oils

The objectives of this investigation are to evaluate the friction characteristics and wear protection capability of low phosphorous engine oils at cam follower contact in the presence of both the fresh oils and the aged engine oils removed from vehicles and to understand the interactions between the lubricant additives and the tappet shim surfaces.


Experimental Details

Friction and wear measurements

Friction and wear characteristics of the fresh and the aged engine oils were evaluated in a motored direct acting mechanical bucket-type valvetrain rig. A single cam lobe from a 2.0L Zetec® engine is mounted on a steel shaft, which is turned by a 2 hp motor. The cam lobe is rotated against a tappet shim held on a bucket tappet as shown in Figure 1. The nose of the cam lobe is offset from the center of the tappet shim to facilitate tappet rotation for friction reduction. The cam lobe and tappet contact area was lubricated by a jet of oil at 85 p.si. at either 50°C or at 100°C. The tappet shim is made out of AISI 52100 steel and the cam lobe is induction-hardened chilled cast iron. The friction torque was measured by an in-line torque meter. The centerline average surface roughness (Ra) of the cam lobe and the tappet shim was 0.2-0.4 µm and 0.2-0.3 µm, respectively.

The wear was measured on the tappet shim by a surface layer activation technique where the entire top surface of the tappet shim was radioactivated by bombarding with a proton beam in a particle accelerator.

Wear tests were conducted at three camshaft speeds: 500, 1000 and 1500 rpm. The duration at each speed was 2.5 hours. Each test ran between 50 to 100 hours and data was collected every 5 minutes. At the end of each test, the lubricant was pumped out and the entire system was flushed twice with mineral spirits for about two hours. The system was then flushed again with the candidate lubricant to remove any remaining solvent and wear debris. The system was then charged with the desired lubricant. A new cam lobe and a new tappet shim were used with each new lubricant.

Engine oils

Table 1 shows two low-phosphorous engines oils evaluated in this investigation and their friction and wear characteristics compared with two factory fill GF-3 engine oils containing 0.10 wt% phosphorous. RO 168 and RO 207 are factory fill oils (MY 2001 and MY 2003, respectively) containing 0.10 wt% phosphorous while RO 206 and RO 208 were developed as prototype GF-4 oils containing 0.05 wt% phosphorous. The formulation of oils RO 168 and RO 207 are similar, with the difference in the detergent system; oil RO 168 contains Ca and Mg sulfonate detergents, while RO 207 contains only the Ca sulfonate detergent. oil RO 206 is similar to oil RO 207 but contains only half of the ZDDP oil RO 208 is similar to oil RO 206 but contains a supplemental antiwear additive. The chemical analyses and viscosities of the fresh oils are also shown in Table 1. All the oils were formulated to SAE 5W-20 viscosity grade. All these oils were put into different vehicles in different fleet tests as shown in Table 2 and then drained from the vehicles for friction and wear evaluation.

Wear performance

It is interesting to note the small amount of wear experienced in this contact and the wear trend is almost linear during the test. It has been observed that a change in speed from 500 rpm to 1,500 rpm has practically no impact on the wear behavior." Figure 3 also compares wear data between oil temperatures of 100°C and 50°C. Wear at 50°C was extremely small due to significant reduction in the severity of contacts due to the increased film thickness resulting from increased oil viscosity. The wear rate under this condition was near zero. However, the wear rate increased when the oil temperature was raised to 100°C again.

The oil viscosity plays a significant role in friction and wear response in the direct acting mechanical bucket-type valvetrain. The increase in oil viscosity would reduce friction by reducing the severe interactions between the asperities of sliding surfaces. Traction measurements were conducted to understand if the observed reduction in the friction torque and the tappet shim wear with used oils is greatly influenced by an increase in viscosity. Figures 10 and 11 show the traction coefficients as a function of the entrainment speed, and the slide-to-roll ratio for oils RO 206 and RO 208, respectively. oil RO 208 showed a large increase in viscosity as the oil aged in the vehicle, while oil RO 206 did not. The traction coefficient vs. the entrainment speed plots were obtained at a 50% slide-to-roll ratio, and the traction coefficient vs. the slide-to-roll ratio was obtained at 1.5 m/s entrainment speed. RO 208 clearly showed a decrease in traction coefficients with the entrainment speed and slide-to-roll ratio, while oil RO 206 exhibited virtually no change in traction coefficients. But both the oils showed significantly lower wear rate and lower friction torque in used conditions than in fresh conditions. This clearly demonstrated that the observed friction torque reduction with the used RO 206 and RO 208 oils can not be explained solely by the viscosity increase. The observed reduced friction and wear must be related to the nature of surface films formed on the contacting surfaces.

The results demonstrated that under mixed lubrication regimes, the friction performance of engine oil improves with oil aging. However, it can not be assumed that the fuel economy of vehicles would improve appreciably with continued aging. There are other component systems e.g., the piston ring/bore contact, bearings etc.. that operate primarily in the hydrodynamic regime where the viscosity plays a significant role. The viscosity increase associated with oil aging would lead to increased frictional loss at these contacts. Therefore, the net fuel economy gain or loss would depend on the balance of boundary friction decrease with aging and the hydrodynamic friction (due to viscosity increase) increase with increased viscosity due to aging. Also, a remarkable improvement in the wear performance with oil aging in valvetrain contact is encouraging. This could be an enabler for achieving higher oil drain intervals although various other factors need to be considered. However, it would be interesting to know how the wear characteristics of other engine components change with engine oil aging.

 

[1sttruck]

Europe has dealt with much higher fuel costs than the US for quite awhile, but see below for an analysis of the benefit of low friction oils; "Generally in Europe, the emphasis in lubricant development has been given on durability and not efficiency, since very high speed driving occurs in certain European countries."

http://ec.europa.eu/enterprise/automotive/projects/report_co2_reduction.pdf

Review and analysis of the reduction potential and costs of technological and other measures to reduce CO2-emissions from passenger cars
Final Report
October 31, 2006

Overall conclusions

Retrofitting of low rolling resistance tyres has positive costs per avoided tonne CO2-eq., but these abatement costs are somewhat lower than for efficiency improvement of conventional, new cars.

Low-viscosity lubricants used in existing vehicles have higher CO2-abatement costs than retrofitting of low rolling resistance tyres;


5.4.1.3 Fuel efficient lubricants

In Europe, a fuel economy test has been developed using a Mercedes Benz M111 2.0 litre engine. The minimum improvement required when measured in the MIII European fuel economy test engine in order to qualify a low friction, low viscosity, and low HTHS (high temperature high shear) viscosity engine lubricant is 2.5%. Such measurements are made against a conventional lubricant that has not been formulated with friction modifier to reduce frictional losses, is of higher viscosity grading and with a higher HTHS viscosity [ATIEL 2006]. Generally in Europe, the emphasis in lubricant development has been given on durability and not efficiency, since very high speed driving occurs in certain European countries.

5.4.1.4 Impact of engine lubricants on CO2 emissions – NEDC and real world
As explained the viscosity and up to some point the additives of a lubricant affect engine friction and the losses caused by it. Lowering the viscosity of the lubricant may reduce friction losses and improve a vehicle's energy performance. This effect will appear both in test cycles and real world driving as it is directly linked to the engine operation. Nevertheless, as mentioned above, a lubricant differentiates its properties under different operating conditions. As a result a lubricant may present better friction reduction properties under different temperatures. A rule of thumb in this case is that the lower temperature gets, the thicker lubricants become and higher friction losses appear. So the reduction potential of advanced lubricants increases. However, NEDC is conducted under standard temperature of 20EC which does not examine the lubricant's performance in lower ambient temperatures which are quite common throughout the year in Europe. Furthermore, the speed profile of test cycles results in a very mild engine operation profile that does not allow high engine speeds. Low engine speeds correspond to reduced engine friction and losses. In real driving conditions, the style of each driver can cause significant divergences in engine friction losses compared to those of the type approval test and in this way decrease or most probably increase the vehicle fuel consumption. Friction reductions that are achieved through better design of the engine are expected to have a uniform effect on the test cycle and real world driving.

5.4.1.5 Present status of application
In its 2005 report on car fuel efficiency, IEA gives a short description of the evolutions in engine lubricant market during the past 20 years [IEA 2005]. In recent years, the viscosity of engine oils has fallen significantly. In the 1970s and 1980s the most commonly used grades were SAE 10W-40 and 15w40. These oils were gradually replaced by SAE 10w30 and 5w30 in light-duty engines during the 1980s. Today, the most commonly used factory fill oil in car and light-duty truck engines in all OECD countries is 5w30, although some fraction of consumers continues to use 10w30 or 10W-40 oil when the oil is changed. More recently, 5W-20 and 0W-20 oils have appeared in the market. 5W-20 oils are now used in many popular cars such as most model year 2000+ Honda cars and most Ford 2001+ vehicles as factory fill oil, while 0W-20 currently is used only in the new Honda Insight hybrid vehicle. Several major auto-manufacturers concede that, 5W-20 oil should be adequate for most modern (post-1995) cars and light trucks, but most manufacturers do not recommend it officially. However, manufacturers specifically cautioned against the use of 5W-20 oils in some high performance vehicles, vehicles subjected to heavy loads or trailer towing, and in very hot ambient conditions.