Castrol Syntec 5w-50, my mechanic says...

[TSoA]

It's the only synthetic oil he will use. Let's just say I trust the guy implicitly, he holds a competition racing licence, owns a Bosch Service Center and is actively involved with some of the top Audi tuners in the USA. A pile of blown European engines is the backdrop for our ongoing conversation, most of those hunks were running Mobil 1. He claims building oil pressure is a problem with Mobil 1 (15w-50, I assume) and he sees many lower engine failures on the M1. I relayed the argument that M1 is the most popular oil and motorheads who will beat-on and destroy their cars just *happened* to be running M1. He says no. He has experienced the same "incidents" that destroyed Porsche and S-car engines on Mobil 1...with the 50 weight Syntec "never" a failure. Again, I trust the guy, 25 years a Master Porsche+Audi mechanic, his dad 40 years a master BMW mechanic. He even said he will not bother discussing motor oils with any other customer except me, but explained the extreme pressures the 50 weight oil handles makes it the only choice for him (and his customers since he had 2 full drums of it) also he "hates" Mobil 1.
BTW- regular oil for his customers is Castrol GTX 15w-40, possibly a HDEO version. Are we missing out on a good synthetic oil with the Syntec 5w-50?

Is the VII shear really an issue? ps I know that SAE 40 or 50 is too thick for some engines, not Euro cars though. Maybe good for hi-mi cars when hi-mi oil is too low-performance.

 

[Last_Z]

It would be interesting to see someone run this oil. The 5W-50 is a group III (according to people here) and as you implied, it would shear, especially with that very wide spread. There is a VOA of it and it's additives looked decent. It would be nice if it was a PAO, I would definitely give it some thought.
Rick

 

[sprintman]

M1 the most popular syn here is 5W50. It gets used here in just about every vehicle no problem. Distributors have 10W30 but it's almost unknown to the general public.

 

[JPowers]

Mobil 1 has had so many formulation changes that it would be difficult to say whether or not it had any effect on the lower engine failures of those cars.

Just because he's a master mechanic/racer doesn't mean you should take every word he says as the gospel truth. It sounds to me like he's sponsored by Castrol.

By the way, are we talking about race engines?

 

[Al]

Well-I can't argue with his experience or his conclusion. And as was pointed out-mobil has changed formulations. The guy has a fixed opinion-and probably will never change it. He may be right-he may be wrong.

 

[dickwells]

I put this in the same category with my mechanics. I have two who I trust and like. They do not know each other. Both of them swear by slick 50 as the greatest thing going. I don't bother to argue with them anymore, but just realize that anyone can have a blind spot you have to take into account.

 

[V6 Diesel]

I used Syntec 5w-50 in a 350 chevy from the time it was a PAO then a groupIII. I recently switched to M1 after reading the negative talk on Syntec. Can't say it hurt my engine any, still running good after 200k miles. Have a UOA posted on it.

Too fairly compare it to M1 I should have done a run with LC/FP which I run with the M1. Maybe if I pick up another batch of Syntec 5w-50 for $2.50 per qt like I have in the past might have to give it another run for comparison.

 

[Spector]

Most people in life have a unique specialty in which they excel. Your friend is a master mechanic and could probably repair any internal combustion engine made.

Is he also an expert in gasoline formulation, lubrication, tire manufacturing etc. Most probably these are opinions (what gas to use, what oil, one brand of tire at what pressure etc) gathered over time and like most of our opinions on this board, not substatiated in fact or the result of studies.

You have to go with what you think is best and makes you sleep at night, that's all that matters in the long run.

 

[Alex D]

Dunno ........ M1 15w-50 is in my opinion one of the best oils out there if your car can stomach the viscosity. It's pretty thick stuff at cold temps. It does have a significantly stouter additive package than the other M1 viscosities and has more antiwear additives than M1s 20W-50 motorcycle oil and even HDs motorcycle oil! Read this article if you haven't.

http://www.fullthrottlewest.com/article_syn.htm

This oil seems to me made for extreme environments such as racing.

[ November 10, 2003, 10:30 AM: Message edited by: Alex D ]

 

[doyall]

Perhaps the 5w50 used by TSoA's mechanic is a totally different formulation than the 5w50 available in North America. It's been know to happen. What color is is?

FWIW, I recently ran across a web site that has about 100 different UOA's posted (in a standardized format), mostly on Porsches, Ferraris & Mercedes using primarily M1 and Castrol oils. The Syntec 5w50 UOA's don't seem to show any worse shear than others from a cursory review. Maybe an in-depth analysis would reveal something different. Here is the site
http://members.rennlist.com/oil/test_results.htm

 

[Dr. T]

The challenge is a simple one...

Take ANY engine in any car you have. 1st do a run of M-1 15-50 and then a run of Syntec 5-50. They're both 50 weights and should therefore perform the same, right? I wouldn't be surprised if everyone that took on the challenge would find that their car ran tons better with the Syntec than with the M-1. Why? From what I could tell, M-1 has a higher coefficient of friction in all their grades and the 15-50 'unmasks' this deficiency the most. Weak, addative package? I couldn't say....just don't race with A1 rated 5-30 and expect your engine to not end up in that same pile...

 

[TooSlick]

I'd agree with Alex, the M1, 15w-50 has the additive chemistry that ALL their Mobil 1 products should have. ...

For example, it's the only grade that has a decent # of ZDDP, as well as some boron ....The 15w-50 also uses thicker basestocks, so the Noack volatility is excellent.

Tooslick
Dixie Synthetics

 

[TSoA]

Thanks y'all for the insight and opinions. Obviously I don't have much to add, I just wanted to throw the subject out there and convey what my mechanic says. I dunno if the 5w-50 Syntec will, for example, help with oil burning but it probally protects abused engines very well. Is it long-life, probally not, but it is ACEA A3 approved and one of the few 5w-50 out there. I actually do understand his reasoning: low temp flow, excellent protection with high HP applications. Anyway, for the record, John is running 26 pounds of boost in his S6.

 

[vvk]

This particular oil is not for every car. I tried it in my Subaru Impreza several years ago and had really bad valvetrain noise on cold startups.

 

[geeeman]

A friends Civic "blew" its engine at the track; and he was using M1 (10W30-15W50 50% mix). Must be that M1...

Oh yeah...he mentioned something about missing a shift; his aftermarket tach showed 10 000 + peak rpm... oops!

Sometimes it's easier to blame the oil...!

 

[G-MAN]

quote:

---

Originally posted by TooSlick:
I'd agree with Alex, the M1, 15w-50 has the additive chemistry that ALL their Mobil 1 products should have. ...

For example, it's the only grade that has a decent # of ZDDP, as well as some boron

---

All grades of Mobil 1 have about the same amount of boron from the VOAs that have been posted.

 

[pinoy99]

Hmmn, I tried 2 quarts of 5W50 + 3 quarts of 10W40 Syntec Blend, pretty much did not help my consumption and noisier(cold) than straight 10w40.

I will try the M1 15W50 next summer;if that does not help, I'll just stick with 10W40 Syntec Blend. Going to GC this/for winter.

 

[Patman]

Syntec 5w50 might as well be labelled 10w40, because it wouldn't surprise me if it turns into this exact weight of oil after just 1000 miles in your engine.

 

[TSoA]

quote:

---

1)My old 1993 Grand Marquis had 169,000miles on it when I went cross country

2)I used M1 15W-50 to control the valve seal-related oil consumption

3)It didn't burn a drop, I put in the Syntec 5W-50 By the time I got back I had added 2-1/2 quarts

4)I never used that oil again

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I try not to dispute much with anyone who responds to my threads, but I have to take your story with a grain of salt.

1)- Hi-mi and worn low-rev engine to begin with, M1 15w-50 is a fine choice, even overkill. Potential for developing problems during a double-trans-continental trip is high to begin with, no doubt you usd more on the return
2)- People here have reported a cases of consumption varying widely upon a switch to synthetic, if that was your situation. Again, an engine with a known problem and the switch might not be helpfull at first
3)- a 5w oil will behave differently when your car is parked if it had seal leaks, passing through more easily. That would account for some diference in oil retention
4)-Sinced you only used that oil once and won't try it again objectively, I can't say your body of experience is enough to draw upon, especially now that both oil's formulations have changed several times

[ November 10, 2003, 04:45 PM: Message edited by: TSoA ]

 

[Alex D]

Is that positive that Syntec 5W-30 is a Group III ?? I thought only some of the Syntec line is Group III such as the 0W-30, 5W-30 and 10W-30

quote:

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Originally posted by Last_Z:
It would be interesting to see someone run this oil. The 5W-50 is a group III (according to people here) and as you implied, it would shear, especially with that very wide spread. There is a VOA of it and it's additives looked decent. It would be nice if it was a PAO, I would definitely give it some thought.
Rick

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