GC, 0w-30 ...Perhaps I should have known?

Not open for further replies.
Aug 2, 2002
This recent data caught my eye as I was looking at some of the recent GC, 0w-30 analysis results ....

ASTM D-4172B, Four Ball Wear Test
40kg pressure @ 150C, 1800 rpms for 1 hour duration

Amsoil 0w-30/TSO..........0.37 mm

Amsoil 5w-30/ASL...........0.40 mm

Syntec, 10w-30...............0.45 mm

Mobil 1, 5w-30................0.67 mm

Yes I realize this isn't the GC, 0w-30 formulation - it's the Group III based, garden variety Castrol Syntec. However, oil manufacturers generally use the same type of AW additive package for their gas engine oils, and the same type of additive package for their diesel oils.

The ASTM D-4172B test isn't really sensitive to the type of basestock used and it's even fairly insensitive to variations in oil viscosity. What it does do is give you a general idea of how effective the AW additives are under conditions of boundary lubrication, sliding contact and very high pressures. In other words, there is some correlation to valve train wear in an actual engine. Before anyone points out that engines don't use ball bearings, I suggest you do some research into the accepted practice of using analog tests throughout the field of materials science and mechanical engineering. You will find they are used all over the place ....For example, the Four Ball Test is required as part of the Mercon V transmission spec.

Given the precision of this test, variations of < .05 mm typically aren't considered significant.
For all practical purposes, the GC 0w-30 and the Amsoil 5w-30 generate comparable results in this analog test.

I eagerly await the all too predictable shrill response from the Mobil 1 crowd. However, I honestly think this helps explain some of the variability we see with regards to valve train and ring/cylinder wear seen in oil analysis testing.

TS makes an interesting point. I would guess that any correlation between valve train wear and the four ball test would be highly dependent upon the engine design as there are many different ways in which valve trains are made, and might also be dependent upon minor sample variations from engine to engine.

TS, do you have four ball data from other oils?

Your headline was " Perhaps I should have known". Known what? You did not answer the question you posed.....

I should have known it was a way to do another Amsoil commercial...very thinly disguised. Geezzzzz
I don't see that as another Amsoil commercial. TS is talking about Castrol oils having the same great results as Amsoil products. I haven't seen Castrol ASTM D-4172B tests data before, now I have a dilemma. I've got two stacks of oil, GC and M1 5w30 sitting in my garage. I usually buy whatever one is on sale. I have great UOA results with GC, now considering this four ball wear test data, I don't really know whether I want to use M1 in my engine or not. May be just for couple of OCI, to establish once and forever for myself that M1 produces significantly more iron?..

Originally posted by tenderloin:
I should have known it was a way to do another Amsoil commercial...very thinly disguised. Geezzzzz

Ummmm....I'm not a proponent of biased product pandering either, but I think TooSlick has that avatar for a reason and has earned his "oily wings".
yugrus LOL

First off there is a header on this thread that says "Post all GC (German Castrol) Topics Here"

sooooo a topic about GC, if it really is about GC (and not M1 bashing), should have been posted there.

Next he happens to post Amsoils test results showing Amsoil "superiority"....but no GC results, just regular Syntec results (along with M1 bashing)and a convoluted attempt to say, well, manufacturers add packs are all the same...

Then he states " I eagerly await the all too predictable shrill response from the Mobil 1 crowd"

Yea this was an innocent thread. LOL

Why would you worry about using M1? Just curious

[ March 09, 2005, 11:29 AM: Message edited by: tenderloin ]
Exxon/Mobil used to address this issue on their faqs on the Mobil 1 web-site. Castrol tech rep. also told me essentially the same thing.

Neither company seems to feel that this is a particularly valid test for an engine oil.

TooSlick is one of the most valuable members here in enlightening and inspiring intelligent technical discussion. That's what we are here for.

[ March 09, 2005, 11:49 AM: Message edited by: haley10 ]

Originally posted by tenderloin:
Why would you worry about using M1? Just curious

Consistently higher Fe levels then, OK, SOME OTHER oils? Am I missing something on that? As for the same (or similar) add packs in different grade oils, that makes sense to me. Does it not at all?

opposed to using the search function


Try using the search function on GC, German Castrol and you will be reading on this board for the next 3 months. Warn your family that you are doing it and not available.
Then search in Automotive General, and spend another couple months reading. In fact if 4 people did a search on GC on this board at the same time, you would probably shut the board down from overload.


Originally posted by BlazerLT:
The increase wear doesn't surprise me seeing the M1 is a thin 30 weight.

The Castrol Syntec referred too is also equally very thin. Maybe even thinner, much like Pennzoil, but the wear #'s speak for themselves. Look for a low 30 wt. or high 20 wt. @ a reasonable oci.
No offense intended, but I agree with a couple of the previous posters.
Why wasn't this put under the "Post all GC topics here" thread?
It does seem like a thinly veiled Amsoil advertisement to me. I personally think that Amsoil's test results lack credibility and their marketing approach completely turns me off.
I also agree that you'd probably be wrong if you made the assumption that Castrol's additive package for GC is the same as the Syntec 10w30.
And finally, from what I understand, the four ball wear test is not a meaningful test for engine oils, yet Amsoil always touts it in their product info.
Well, I have a very recent with Mobil 1 5W-30.

Aluminum 2
Chromium 1
Iron 7
Copper 1
Lead 2
Tin 4

I don't see these as significant wear numbers. I was planning on going to Amsoil but have not seen a UOA near this for my vehicle - Blazer 4.3 I think the bottom line is put it, do a UOA and go from there.
I'm glad that TooSlick posted these 4-ball wear test numbers. The Series 3000 HDD 5w-30 oil shows a 4-ball test result of 0.40mm according to the Amsoil Corporate website. The test parameters appear to be identical to those shown in TooSlick's post. I find it interesting that the ASL product has the same 4-ball score as the HDD and it costs $2.00 or so less per quart. That would make the ASL product a heck of a bargain if the oil didn't have a tendency to thicken to a 40 weight in as little as 8k miles in some applications according to the uoa's I've seen on this forum and on some other's.
It is not that he posted. It is he intentionally mislead everyone into thinking he was talking about GC when in fact he was not. It was a post touting Amsoil, and trashing M1. The title of his post was a rouse.

That maybe his business, which is fine and dandy. Just don't be so slimy about it here.

I do not care one bit how good Amsoil is.. Because of the way so many sell it, I will never use it.

And you know what you can do with your 4 ball test.

Apologies to the Amsoil dealers who are honest.

Originally posted by SMILEY:
Why is there just one thread for GC??? That just seems ridiculous to me. How many threads have we seen about M1 or Chevron Supreme or Amsoil?

This makes it harder to find specific information on GC as now I have to read through 75+ posts as opposed to using the search function to find a specific topic related to GC.

I always like to add that "I may be missing something" when I go on a rant as I dont always know better.

The poor little elves. They don't get respect.
I think TooSlick generally gives good oil advice. I also believe the Amsoil he sells is excellent oil. But, the title of this thread is misleading.
Thanks for posting the information TooSlick. For me that's what this board is all about. Exchanging information and learning about lubrication. That's all I see here. Now that I have that out of my system. Maybe there is some correlation between the results and the higher PPM of iron we see in SOME of the M1 UOA's. I must say it would be interesting to see the results using GC. All IMHO, I'm certainly in my infancy when it comes to any aspects of lubrication.
Amsoil uses the 4-ball wear as a selling point for their oils. Only problem here is that Redline's top chemist stated that the 4-ball wear is not a good measure of how an oil will protect. XOM will tell you this as well. Not sure I buy into Ted's point but it is a good one.

Another issue I have with it is the variation you see with different grades of M1. They had the 0w-30 M1 at 1.60. Do you really think it's that much worse at protecting your engine compared to the 5w-30 .67mm M1?
Not open for further replies.