5w20 Safe or UnSafe

Pennzoil motor oil
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I can't believe we're even discussing this with the WEALTH of information and used oil analysis on this site using these oils. I suppose it's cyclical. These things are debated and the evidence is great and fairly conclusive, then nothing. Then a new group with the same questions comes along and initiates the same stale rhetoric.

It's like the old guy that "has been using straight 20 or 30 weight in his car for 40 years". Never mind the fact that technology improves and vastly changes things. He's convinced that what he has been using is the best because it was 40 years ago.

I agree with Gary. I have not seen Ford or Honda publish any of that info.
 
Originally Posted By: FrankN4
I found this in a Google search on viscosity. I agree completely.

"Thinner motor oils such as 5W-20 or even 0W-20 are becoming more popular these days and are even specified by some OEM's (FORD & HONDA)

Although these oils are promoted as "energy conserving" they generally trade a gain of less than 0.1 MPG in Corporate Average Fuel Economy (CAFE) for shorter useful engine life.

FORD which has previously designed cars to have 10 year or 150,000 miles life has reduced the mileage life expectation to "beyond 100,000 miles" on vehicles that are operated on SAE 5W-20 Motor Oil.

HONDA only claims "useful life" as 7-years or 70,000 miles in EPA certifications for their CIVIC which uses SAE 5W-20 Motor Oil, while the previous model that utilized SAE 5w30 Motor Oil was certified for 10 year or 100,000 mile durability.

By contrast Mercedes-Benz recommends use of ONLY Synthetic Motor Oil that is at least SAE 5W-40! This is a recent increase in recommended viscosity from SAE 5w30. Apparently customer research indicated that engine longevity is more important to typical MB customer than fuel economy."



I can speak from experience with my car:

Year 2005( Year 2006(>=) to current SAE 5w-20

I can (almost) guarantee you my car will last the requisite 250-300,000 miles and I will make this promulgation right now, right here and guarantee it. If someone wants to print this out and put it in a capsule and bury it until this inevitably becomes true, that would be fine.

(I am just as curious as you and this is the only way to know)
 
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I've been away from this forum for maybe a year, and it is nice to see the Louis LaPointe and the 5W20 debate is still alive.

I am going to hide under my rock again...
 
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I'm still hoping someone can dig up the guy who said not to use synthetic oil because it will form a lapping paste in your engine. He was so authoritative ...the depth of his conviction ... it was one smooth presentation.
 
I dunno ..but he was on another message board ..I think it dealt with Corvettes or bowtie something or other. It was too funny.

Lapping paste
crackmeup2.gif
That was so choice ..so perfectly ridiculous.
 
Gary

I am searching trying to find the site again. There are a million, +/-, sites that come up with the search viscosity. I remember it had something to do with tribology and engineering.

One thing I did discover is that some GM engines made 18 years ago had a bearing clearance of X and ring to wall clearance of X. They mostly called for a 10W-40 oil in temps above 0F. Today, these engines still have a clearance of X and they call for XW-20 or XW-30 year round. The only real difference I can find in my engine is that it went to roller lifters and ball bearing rocker arm pivots. That is why I feel so comfortable with the heavier grade oils, that plus over 1,000,000 miles without a problem.
 
Oils are much different now, Frank. Before, you had 3 or 4 typical choices that were offered to the public for gasoline engines.

HD SAE 30 ..labeled "GOOD"
10w-30 ..labeled "Better"
10w-40 ..labeled "Best"

They also typically offered 20w-20.

The fleets may have had 20w-40.

The 40 grade sheared like crazy and wasn't in service very long anyway. You had tons of fuel dilution/washdown/combustion deposits/etc.. due to numb carbs.

My 75 HD emissions C20 extended the OCI 1000 miles if I used unleaded fuel.

There were lots of reasons to use 20w-50 or heavier weights/grades that just aren't applicable anymore. It's not like you can't use them if you want to ..I think I gave ample examples with the Crown Vic in Texas using 20w-50 and how it's not unlike someone using 5w-20 in Nebraska over the span of starting temps that both may see for most of the year.

The main thing is that you're pumping motor honey with no gain in utility and a whopping difference in parasitic loses. Going down a grade below spec is always something that should be well thought out and not done blindly (but I did just that with M1 in several vehicles in the mid to late 70's where no vehicle was spec'd for a 20 weight year round) ..but going up a grade should merely simulate a colder starting and operating temp from a viscosity standpoint.
 
Originally Posted By: Gary Allan
Originally Posted By: TallPaul
"NEVER use 5w30 or 5W-20 oil because it is closer to a grinding compound than a lubricant." --Louis LaPointe (paragraph #5)



Well, then ...I guess we need to rethink things just a bit.


If I'm using a grinding compound in my crankcase, shouldn't my FE numbers be higher? LOL
 
Originally Posted By: TallPaul
"NEVER use 5w30 or 5W-20 oil because it is closer to a grinding compound than a lubricant." --Louis LaPointe (paragraph #5)

I thought you were joking. Then I saw this gem:

Quote:
Old photo of Chevy 427 with one-barrel truck floatless carburetor. Mileage soared from 9 MPG to 28 MPG with this one change alone. Good example of the power of vaporization. Power and torque remained strong, by the way. The carburetor originally came from a six-cyl Chevy truck with a big throttle valve. Great throttle response too. It is simple to install a one-barrel carburetor on a V-8 engine. You could double or triple your mileage. We have recently found other installations of single-barrel carburetors on V-8 engines and will be shown here in the near future.
http://www.brightgreen.us/lubedev/smartgas/tips.htm
crazy2.gif
LOL.gif
 
Originally Posted By: globey
Originally Posted By: Gary Allan
Originally Posted By: TallPaul
"NEVER use 5w30 or 5W-20 oil because it is closer to a grinding compound than a lubricant." --Louis LaPointe (paragraph #5)



Well, then ...I guess we need to rethink things just a bit.


If I'm using a grinding compound in my crankcase, shouldn't my FE numbers be higher? LOL
No, not if you are using a high efficiency oil filter.
 
BTW, I heard in the old days when a car's rings didn't seat after a reasonable break-in period, they would pour some Bon Ami in the intake while revving it to re score the cylinder walls for a second chance at seating the rings. Sounds like fun. Maybe work even better with 5w20 oil.
 
our neighbor has run CASTROL SYNTEC 5w-20 in his '99(?) CIVIC sedan since 10,000 miles and currently has over 240,000 + miles on it and still going strong . Uses it to go to work on interstate for a 120 mile round trip per day . Revs the cr*p out of it too , seen and heard it for myself . Doesn't give it any warm up time , just start and go ! ;- )
 
forget to mention that he said that the CASTROL SYNTEC 5w-20 gets changed at about every 10,000 miles and the gear oil is from day 1 . Talk about the luck of the IRISH , eh ? Or is it that we all worry too much ? These FORUMS sure don't help with us current / potential worry warts . :- )
 
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Originally Posted By: TallPaul
BTW, I heard in the old days when a car's rings didn't seat after a reasonable break-in period, they would pour some Bon Ami in the intake while revving it to re score the cylinder walls for a second chance at seating the rings. Sounds like fun. Maybe work even better with 5w20 oil.


That is actually true. The engine was a 265 CI V8 used in the 1955 Chevrolet. I saw a documentary that told of mechanics that used the Bon Ami. It seems the 265 V8 had to be delivered to the assembly line for a cost of $100.00. There were numerous problems with that engine. The GM engineer said that engine almost put them out of business and they were seriously considering buying V8 engines from Pontiac.
 
On page 4 of this dicussion list Frankn4 found a site that site that promotes heavier oil, and uses warranty lengths for evidence. Many people noticed the "selective ommissions" that the author made, ignoring vehicles warranted 100K, and lifetime, using 5W20.
Basically the Authors claim that you will be lucky to get 100K miles with 5W20 oil, but only present emotional claims and never any evidence.

I sent them an email, their response showed that they had little or no knowledge of lubrication basics.

Now for some anecdotal evidence: My 1994 lumina APV, 3.1 Litre V6 is now at 239 k, and tows a 4880 lb trailer on a commercial basis. I use only Mobil 1 0W20, and change every 20 K. The engine burns no oil and has had o repairs.
No, I have never run an oil analysis, and see little reason to do so. The days of running tar (30,40,50 weights) in your engine are gone!!
 
fsskier

Where did you finally find them? I have been searching to try and find them again. All I can remember is that it was a site that had to do with tribology and engineering, possibly for synthetics.
 
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