Castrol Syntec vs. Mobile 1

[baomo]

I've been using Castrol Syntec for sometime, 10W40. I've seen a couple of posts that refer to Syntec as a scam and a bad oil. Could someone explain why this is and compare it to say Mobile 1 or something comparable (forgoing Redline and Amsoil or the more expensive end of the spectrum) that I can pick up retail.

 

[Gene K]

Castrol Syntec is not a bad oil. But most grades are Group III oil formed by either hydrocracking petroleum or slack-wax. Until Castrol started marketing Group III oils as synthetic this had never been done before. Mobil lost the lawsuit they filed over Castrols labeling of the cheaper to produce Group III basestocks as synthetic so now the majority of the market has gone Group III. Most consumers are none the wiser. Most people are upset because Castrol reduced the production cost of their product with a move to the lower cost basestock without passing on the price to the consumer. Mobil 1 SuperSyn is a Group IV/V hybrid. Roughly 85% Group IV/ 15% Castrol Syntec OW-30 (German Made) is a Group IV/V oil and widely considered one of the finest oils you can buy. The 5W-40 Castrol Syntec (Belgium) is likely primarily Group III but supposed to be their second best oil. Best American made Syntec is likely the 10W-40 Group III. Amsoil only uses Group III in the XL-7500 series which is clearly labeled as such. Redline uses the highest percentage of Group V basestock of any commonly available oil. Gene

 

[haley10]

Boy, have you ever opened up a can of worms. This subject has been beat to death. I won't add to beating the dead horse. Syntec 10W-40 is an excellent oil. I am trying it out right now. The 0W-30 German Castrol is an excellent product. I consider these and Mobil 1 to be on the same playing field. I use both, bepending on the application. Syntec is not a bad product.

 

[haley10]

Motorbike is on vacation, so he can't help me out here, but Syntec 10W-40 is GroupIII, Slack Wax XHVI 5.2, and PAO. It's an extremely thin 40 wt. 13.1@100C It doesn't have an exact M1 equivalent so it's not fair to compare. It's rated A3/B3, so it's worth the money, imho.

 

[yannis]

quote:

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Originally posted by Gene K: Castrol Syntec OW-30 (German Made) is a Group IV/V oil

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It looks like it is IV/V but unless i have missed some episodes its formulation remains unclear.

 

[Gene K]

Correction noted: To be more specific about the Castrols: 0W-30 is presumed to be Group IV/V. 5W-40 is presumed to be primarily a Slack-Wax Group III. 10W-40 is presumed to be a blend of Petroleum and Slack-Wax Group III with a little PAO (Group IV). At least as of the last episode of this little soap opera. These are the only Castrol Syntecs I might use at the prices available to me. I am currently running the OW-30 in a GM 2.2L OHV. Gene

 

[haley10]

quote:

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Originally posted by yannis:

quote:

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Originally posted by Gene K: Castrol Syntec OW-30 (German Made) is a Group IV/V oil

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It looks like it is IV/V but unless i have missed some episodes its formulation remains unclear.

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I missed it, too. The Green Elixir remains a total mystery to me. I'll run it starting this Winter, but I would like to know more. I thought there was going to be a fund to get a real analysis?? Well, I guess it's the results that count, anyway.

 

[hungdynasty]

There is 2 kind of Castrol synthetic oils sold in Hong Kong Castrol RS 10W60 Castrol RS 0W40 I'm not sure if they are actually the "German Castrol" in America but I'm pretty sure they are sold in Europe with the same names since the bottle label 'Made in Europe',with some european (non-english) descriptions on it.

 

[Gene K]

The OW-30 Syntec was originally the SLX 0W-30 in Europe. The 'R' or 'RS' Castrols here are gettable but generally only from Race/Performance/Tuner Shops. I believe they may be privately imported. Gene

 

[jthorner]

The few posted UOA results from Castrol Syntec have generally been very positive. The controversy is over the definition of "synthetic" and the marketing thereof. Castrol was the first to market Group III oils as synthetic and has taken heat from many enthusiasts over it. However, the results of those using Syntec have generally been excellent. Chevron, Shell, Pennzoil, Valvoline, Exxon and others all now also market Group III oils as sythetic oils, yet few people have the passionate hatred for those companies or their Group III oils. Grudges are hard to let go of. Here are recent results I posted for my '96 Volvo running Castrol Syntec 10W-30: Volvo 850 4,950 Miles on Syntec Report Oddly enough, you will find very few UOA results posted here on plain old US made Syntec. People are gaga crazy for the German made 0W-30 stuff. Results wise I see nothing wrong with Syntec. John

 

[haley10]

jthorner, I think it is also relevant in you uoa thread that Terry Dyson said that he has seen some good results with these oils.

 

[Santo Fontana]

IMO, if you used Syntec and M1 in the same engine, with the same weight, Syntec will give you better wear numbers, especially iron. Why?

 

[radiometer]

Motorbike is on vacation, so he can't help me out here, but Syntec 10W-40 is GroupIII, Slack Wax XHVI 5.2, and PAO. Haley10, How do we come to the above conclusion? This is most interesting.

 

[Gene K]

I dont really understand why M1 shows high iron. However it does tend to trend down to lower levels with long-term use. There is a 1988 Chevy 5.7L TBI here in town with 600K mi on M1 10W-30 with Timing Chain, Rocker Arms, and Valve Seals Replaced at 480,000 mi. Uses 1 QT per 10,000 mi (Normal change Interval) and shows less than 1 ppm per thousand mi Iron wear. It has used M1 since the first change at 3000 mi. Changes Every 7500 mi after that until warranty was up and every 10,000 mi since. Some have suggested that a sacrificial layer is being formed on the iron in the same way that happens with Redline and Soft Metals. krholm, I assume he used the CAS numbers from the MSDS. Just a guess. Gene

 

[radiometer]

Castrol Syntec is a 100% fully-synthetic motor oil. Castrol SYNTEC is not made with petroleum base stock. Synthetic motor oil starts with synthetic base oil. --------------------------------------- I sent Castrol's "Ask the Expert" a question about their 10W-40 and the above is part of their response to me. How do you guys take it?

 

[Pit Bull]

For warranty reasons I have to change oil/filter every 5K miles. Dealer uses Castrol. I decided to go with Castrol GTX every 3750 miles versus Castrol syntec every 5000 miles. Cost is less, Plus based on UOA that I've seen done on Toyota 4.7 V8 engines the 4.7 V8 is easy on oil. So I would rather have dino oil with shorter interval changes so the oil stays cleaner. Now between Mobil 1 and Castrol Syntec, if you were talking 5-6K mile OCI I don't think it would make a big difference. If you are talking 10K oci then I would go with the Mobil 1. JMHO it's all about the $$$.

 

[baomo]

ok, i've used syntec 10w40 for some time now with no complaints, seems to stay clean up to about 8k to 9k. i'm familiar with the hydrocracking petroleum process but confused with the slack-wax? what does that mean. i forgot that mobile 1 doesn't have a 10W40. they have the 0W40. i try to stay away from 0W anything.

 

[haley10]

quote:

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Originally posted by krholm: Castrol Syntec is a 100% fully-synthetic motor oil. Castrol SYNTEC is not made with petroleum base stock. Synthetic motor oil starts with synthetic base oil. --------------------------------------- I sent Castrol's "Ask the Expert" a question about their 10W-40 and the above is part of their response to me. How do you guys take it?

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It's a waste of time, as with most oil companies. Check out Motorbike's VOA and the associated links. Castrol call severely hydrocracked Group III synthetic. Some do not. It's all beginning with something out of the ground, anyway. Much PAO syn is from Natural Gas originally. We can split an atom, but have we ever "synthetically" created one?? I just look at the specs. The "synthetic" argument is a moot point.

 

[Gene K]

quote:

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Originally posted by krholm: Castrol Syntec is a 100% fully-synthetic motor oil. Castrol SYNTEC is not made with petroleum base stock. Synthetic motor oil starts with synthetic base oil. --------------------------------------- I sent Castrol's "Ask the Expert" a question about their 10W-40 and the above is part of their response to me. How do you guys take it?

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Well someone better tell them to change all their MSDS because they show a baseoil made with petroleum Feedstock for most grades. I dont think the Feds get along with people lying on those documents to well. A better question would be "What Group Base Oil Does your 10W-30 Castrol Syntec Use"? According to the lawsuit they won there is no such thing as "Synthetic Oil" it just means better than standard. So I guess there answer means it is better than the basestock we use for Non-Detergent SAE 30. Gene I am neither anti-Castrol nor pro-Mobil. The only products I use made be either is Delvac 1300 and GC 0W-30. Just trying to cut through the marketing BS. They each have excellent products and each have average products. Just for the record I dont care for Castrol Syntec 5W-30 or Mobil Drive Clean on a Bang for the Buck Basis. However I would use either before I ran a car 2 QT low on oil. Gene

 

[haley10]

quote:

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Originally posted by baomo: ok, i've used syntec 10w40 for some time now with no complaints, seems to stay clean up to about 8k to 9k. i'm familiar with the hydrocracking petroleum process but confused with the slack-wax? what does that mean. i forgot that mobile 1 doesn't have a 10W40. they have the 0W40. i try to stay away from 0W anything.

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Don't know what car you have, but GC 0W-30 turns in impressive results. Just cause you live in a hot climate, don't fail to look at the GC. It's a very robust 30 wt.