A3 oil

buster · Aug 18, 2003

Is there any reason why you can't run a good synthetic that is not A3 rated in a car that calls for an A3 oil? Also, does anyone ever think Mobil 1 30wt will be A3 rated? With more and more imports coming over here, you would think Mobil would care more about wear and A3 rating then a ridiculous savings in the MPG department.

TR3-2001SE · Aug 18, 2003

All I can tell you is if I had a car requiring a European A3 oil I would use 10w-30 Mobil 1 with absolute confidence.

Ken2 · Aug 18, 2003

Mobil 1 10W-30 is rated ACEA A1 for a good reason--it can't meet the A3 spec. Don't assume that any synthetic is a superior oil. Synthetic oils vary in quality...they're only as good as the oil blender wants them to be.

A3 has higher shear stability, higher High Temp/High Shear viscosity, lower evaporative loss, and less oil thickening than A1. ACEA A5 oils have lower HT/HS viscosity, pass a fuel economy test, and match A3 in other respects.

I agree, there aren't many A3 rated oils on the shelves of popular stores, especially in the 5W-40 viscosity grade. I'm using Schaeffer's 5W-30 which is A3 and moderate cost, but availability is problematic for some.

Ken

[ August 18, 2003, 08:49 PM: Message edited by: Ken2 ]

buster · Aug 18, 2003

I agree with both of you. I have to say though that even though M1 10w-30 is not A3 rated, I think its as good as one or as capable as most A3 oils. I know I'm only speculating by this oil doesn't shear a bit.

like a rock · Aug 18, 2003

Buster- I am using ss 10w-30 in my Saturn L-300 in the second month of a four month interval. No oil consumpton to date and the valve cover area is sprakling clean as I would expect. I think the A-3 rating might be a little bit of a non issue for this oil. Heck it delivers great UOA after UOA. Some of the more expensive A-3 synthetics do not perform as well.

Andrew · Aug 18, 2003

There are quite a few A3 rated mineral oils appearing on the shelves too.

G-MAN · Aug 18, 2003

quote:

Originally posted by Ken2:
Mobil 1 10W-30 is rated ACEA A1 for a good reason--it can't meet the A3 spec.

Ken, it's rated A5, too, and A5 is just as tough a spec as A3 with the exception of the HT/HS having to be >3.5.

A5 is the ACEA low HT/HS extended drain spec, BTW.

F1Crazy · Aug 18, 2003

quote:

Originally posted by Andrew:
There are quite a few A3 rated mineral oils appearing on the shelves too.

Not in a 30wt.

Dr. T · Aug 18, 2003

Yes. It means that particular 30 weight lacks the cojones necessary for the job. Truth is, all grades of M-1 oils are thin already. So, it's no wonder the 30 weights can't cut the mustard with respect to A3. But, it's North America...who cares about A3, right? Truth is, Mobil only needs to be as good as what else is on the shelf. What other 30 weights OTC are A3? I can just think of one....the German Syntec.

If your engine requires an A3, why would you skimp out? Why not use M-1 0-20 then? It's not A3 either...but, Ford and Honda say it's OK. Do you see what's happening?

All manufacturer's would tell you to use WD-40 for engine oil if they could. The thinner, the more fuel efficient they are. Longevity? Well, that's for the engine/car manufacturer's that care or care that the engine lasts beyond the warranty period. For the rest of us, there's 3k oil changes, auto-rx or a new car/engine.

G-MAN · Aug 18, 2003

quote:

Originally posted by Dr. T:
Yes. It means that particular 30 weight lacks the cojones necessary for the job. Truth is, all grades of M-1 oils are thin already. So, it's no wonder the 30 weights can't cut the mustard with respect to A3. But, it's North America...who cares about A3, right? Truth is, Mobil only needs to be as good as what else is on the shelf.

Yadda, yadda, yadda...

You and metroplex ought to get together and start your own web site. I think the domain name www.ihatemobil1.com is available.

Fillherup · Aug 18, 2003

Just one viewpoint, but a friend just came back from three weeks in Europe. He got a free rental upgrade to a car that was top-end rated around 200KPH. He told me they that they really don't care aout 0-60 times, since most cars have small engines that the middle class can afford. But they asked him how fast the car would go. And I don't mean reading the owners manual. They wanted to check it out in real time. Apparently WOT and for extended periods is nothing unusual for small engines on the high speed roads.

If this is common, I can see why you would want an A3 rated oil real fast.

Patman · Aug 18, 2003

quote:

I'm using Schaeffer's 5W-30 which is A3 and moderate cost, but availability is problematic for some.

I know this will ruffle a few feathers, but I have my doubts as to the Schaeffer 5w30 being a true A3 oil. Their specs list the viscosity at 10-12cst at 100c, and the HTHS is 3.5. But I don't see how a batch which comes in at 10cst could possibly still have a 3.5 HTHS. A recent UOA showed their 5w30 finishing up at about 9.6cst, I doubt the HTHS could be anywhere near 3.5 at this viscosity, I bet it's closer to 2.9-3.0.

I will have a UOA on this oil in a week, and I'm interested to see if this batch is anywhere near 12cst. I've yet to see very many UOAs on this oil where it's close to the top end of their listing on the specs. Based on my oil pressure readings, I'm predicting my batch of 5w30 will finish up around 9.5 to 9.8 cst at 100c.

I do believe this is a great oil, I just don't quite believe it's HTHS is possible on the thinner batches. Name one other oil out there which shows an HTHS of 3.5 AND is 10cst at 100c. I've never seen one.

Dr. T · Aug 18, 2003

The real answer to buster's post lies in ACEA's guidlines. A1, A2 and A5 stipulate the following warning: "These oils may be unsuitable for use in some engines. Consult owner manual or handbook if in doubt."

This means if your car stipulates A3, then A1, A2 and A5 may be unsuitable. I think the "may" alludes to the chart that moribundman posted earlier referencing different 5-30's on different sides of the chart. Although it refers to VW specs, it clearly distinguishes 2 vastly different specs for differing 5-30's. Most likely...one A3, the other not...

F1Crazy · Aug 18, 2003

quote:

Originally posted by Patman:
I do believe this is a great oil, I just don't quite believe it's HTHS is possible on the thinner batches. Name one other oil out there which shows an HTHS of 3.5 AND is 10cst at 100c. I've never seen one.

Castrol TXT Softec Plus 5W-30:
ACEA A3/B3
viscosity at 100C is 11.9 (in Shaeffer's range)
HT/HS 3.5cP

Patman · Aug 18, 2003

quote:

Originally posted by F1Crazy:

quote:

Originally posted by Patman:
I do believe this is a great oil, I just don't quite believe it's HTHS is possible on the thinner batches. Name one other oil out there which shows an HTHS of 3.5 AND is 10cst at 100c. I've never seen one.

Click to expand...

Castrol TXT Softec Plus 5W-30:
ACEA A3/B3
viscosity at 100C is 11.9 (in Shaeffer's range)
HT/HS 3.5cP

You're missing my point though, that oil is listed at close to 12cst and has a 3.5 HTHS. I'm looking for evidence that it's possible for an oil of only 10cst at 100c to have an HTHS of 3.5. I don't believe it's technically possible, at least not with affordable base stock/additives. Redline lists their 10w30 as having an HTHS of 3.8, and a viscosity of 10.7cst, however their method of calculating HTHS shows slightly higher numbers compared to the usual methods, plus in reality their 10w30 is not 10.7, but much closer to 11.5 to 12.0 from what we've seen on here.

Dr. T · Aug 18, 2003

I think A3 is a relatively new (1999) phenomenon in North America. No readily available OTC xW-30 oils are A3 except for the recent German Syntec. So maybe for the next M-1 reformultion....lets see...that would be in...like, 2 years???

highmiler · Aug 19, 2003

What about Mobil 1 15W-50? It is A3 rated and available everywhere in NA.

Ken2 · Aug 19, 2003

But few engines are built for 15W-50 oil.

Ken

Patman · Aug 19, 2003

quote:

Originally posted by Ken2:
But few engines are built for 15W-50 oil.

Exactly!

Although curiosity has me wondering how that oil would do in my LT1 Firebird. One of these days I might just run a 3k interval and see how it fares. I know it's probably too thick, but it would be nice to have a UOA to prove it to myself.

highmiler · Aug 19, 2003

I'll bet that many of those engines in cars sold in North America would do just fine on Mobil 1 15W-50 when sold in Australia and other countries with hot climate. What do the manuals of those cars say about oils to be used over there?

I'd like to see UOA's that show the harm this oil does to cars "not designed" for this oil viscosity.

For fuel economy reasons I use 5W-30 both in my 01 Toyota Echo and my 98 K1500 Chevrolet but I am not entirely convinced that a thicker oil would harm those engines.

A3 oil

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