Engine Oil Myth

[va3ux]

Originally Posted By: Towel_Rail
Originally Posted By: Mike_dup1
Some of you guys are not happy with any info, all you do it knock everything you don't agree with. No open minds it seems.


As a critical thinker, I question both those who spread "myths" and those who claim to "debunk" them. I also like to see peer-reviewed studies and primary sources, not just a bunch of statements in a quote block from some guy. Don't take it personally.

- Scott


Except in this case, the debunker has simply restated facts that are common knowledge and well documented within the lube industry over the past couple of decades. There's nothing new in the 'debunker's claims' - he's just summarized it nicely.

 

[73 BGT]

Don't forget the "myth" that by mixing eastern and western crudes the oil will sludge! (Don't know about middle eastern and western) RP

 

[HM12460]

interesting read. i only believe in 3 things for certain. girls, rock&roll, and chevy trucks.

 

[Towel_Rail]

Originally Posted By: va3ux
Except in this case, the debunker has simply restated facts that are common knowledge and well documented within the lube industry over the past couple of decades. There's nothing new in the 'debunker's claims' - he's just summarized it nicely.


I agree that much of it makes sense. Most of my contention is with the ZDDP argument, and whether a lab test proves that a new formulation is sufficient to protect a valvetrain design that is no longer widely used in the industry.

Most of all, I just like the OP's hissy fit that came when not everyone changed their minds to agree.

- Scott

 

[Towel_Rail]

And actually, I could leave well enough alone, but here is where I am not 100% convinced by the new valvetrain wear tests:

Quote:
- Sequence IVA tests for camshaft scuffing and wear using a single overhead camshaft engine with slider finger (not roller) followers.

Overhead cams have much lower spring pressures than a pushrod engine, so cam/lifter wear isn't much of an issue.

Quote:
- Sequence IIIG evaluates cam and lifter wear using a V6 engine with a flat-tappet system, similar to those used in the 1980s (fig. 5).

Here's where I really wanted to see the picture, which I would guess to be the engine in question. Didn't V6s from the 1980s tend to have overhead cams?

For me, the acid test is a pushrod engine running stock or moderately higher spring pressures. Or heck, how about a good old VW engine, where each cam lobe has *two* lifters rubbing on it!

GM has tested a lot of things and said "no problems were uncovered." I reserve the right to be skeptical.

- Scott

 

[Mike_dup1]

I am glad there are so many experts here to refute the opinions expressed. Its goes to show he was right about one thing.
Quote:
Like other myths before it, history teaches us that it will probably take 60 or 70 years for this one to die also.


Here is you figures:
Figure 1

Figure 2

Figure 3

Figure 4

Figure

The site with the article prevents linking of images so I had to find a host.

 

[BrianWC]

Originally Posted By: Towel_Rail

Here's where I really wanted to see the picture, which I would guess to be the engine in question. Didn't V6s from the 1980s tend to have overhead cams?



Uh, no. Not American ones. GM is just NOW introducing OHC V-6s on a widescale. FOr certain, Ford did much earlier, but most 80's cars were still OHV unless they were fur-in cars.

 

[Gary Allan]

Quote:
Quote:
- Sequence IIIG evaluates cam and lifter wear using a V6 engine with a flat-tappet system, similar to those used in the 1980s (fig. 5).

Here's where I really wanted to see the picture, which I would guess to be the engine in question. Didn't V6s from the 1980s tend to have overhead cams?


The Sequence IIIG test is brutal ..and is performed on a 3.8 GM V6 (iirc).

The missing element that the guy isn't saying is that the test is a PASS:FAIL test. Some oils do better than others .even though all PASS. SWRI - ILSAC GF-4 Sequence IIIG

 

[Rock_Hudstone]

From GM Techline Dec 2007
Quote:

However, phosphorus is a poison for exhaust catalysts. So, ZDP levels have been reduced over the last 10-15 years. It's now down to a maximum of 0.08% for Starburst oils. - Thanks to Bob Olree – GM Powertrain Fuels and Lubricants Group

Curious, catalytic converters have been required on new cars for a long time, (since 1975 to be precise). However, GM and other manufactures didn't seem overly concerned about phosphorus "poisoning" exhaust catalysts before the EPA forced them to extend the warranty on emission control equipment in the last few years.

In fact, as recently as 1996 even regular SH grade passenger oils typically had P/Zn levels in the 1200/1300 ppm range and I don't recall any rash of exhaust catalyst failures.

 

[NovaMan]

When did the EPA first require automakers to warranty cats for 100k miles? And is 100k miles the actual spec?

 

[slalom44]

Originally Posted By: NovaMan
When did the EPA first require automakers to warranty cats for 100k miles? And is 100k miles the actual spec?

No, 80k is the actual spec, and it was mandated in 1995.

EPA Emissions Warrantees

 

[mcshooter]

back to the penn.crude. do any of you folks remember speed sport oil?? was at a mechs seminar and remember the bragging about penn. crude was better since it had no napha to refine that all other crudes .this was in 1960 , any old folks around

 

[ted s]

glad to see that is all resolved.