I remember guys scooping up German Castrol 0w30 b/c it was superior synthetic (and it was green!). I could never find it to try unfortunately, however, there is Castrol Syntec 0w30 (Made in Germany on the label, NOT GREEN in colour) on sale here. OK, is this stuff as good as the "old" GC? My car is only summer driven and has no oil burning issues with the 5w30 synthetics I use now (Amsoil, Mobil 1 etc). I would like to add, my car runs fine with these oils, no unusual noises, no piston slap etc. This oil is cheaper than the Amsoil, is it the worthy replacement for the GC? Too thin? Any insight? Am I being thrown by the Made in Germany and 0w30 labels? Thanks!

 

Somebody? Anybody?

 

Which one is more important to you? Save $$ for cheaper oil for your motor or buy the good stuff?

I on the other hand not fortunate enough to buy the GC made in Germany however I did settle with made for EUROPEAN car Mobil 1 0W-40 oil. My car idles healthy at 40 on hot, 50-55 on cold. I tried Castrol EDGE, I saw my car idling 25-30 hot, 40 on cold.

 

OP, i have been running the GC in both versions for 5 years. not a single problem. oil pressure is and has always been 40+, oil changed every 3500-4000 miles. Ran Amsoil once, then went back to GC.

 

Thanks for the responses guys! Alright, bene, my real question was about GC which is waaay cheaper than Amsoil, yet it has an almost "cult" following with some members here. I've been running Amsoil, so that basically answers your pointed question about going cheap or not. I don't want this thread to go the pissy way some others have gone with the cheap-***-who-cares what oil crowd VS the self righteous nothing -is -too- good-for-my car crowd! Castrol Syntec (0w30, German made) VS GC anyone? Okay, cookba, why did you switch back from Amsoil to GC? Differences in the way your car sounded etc? This is the info I'm after!

 

seemed like the Amsoil burned a little less than 1/2 quart in the 4k miles i drove on it. Never burned any with GC, the car drove the same, sounded the same so i went back to GC. oil pressure was the same using both as well. for what its worth, when i cant find GC i run Pennzoil Plat 5w30, runs just as good too.

 

^ Thanks for the first hand knowledge! I take it it the GC was the 0w30?

 

GC is that good. I used to buy it for my camaro all the time until I moved here in England. The closest one I found to have the almost the same quality is Mobil 1 0W40. I'll look around if UK have their own version of GC here.

 

^ Interesting about the Mobil 1. 0w40. Do you know about the Castrol Syntec 0w30 German made? Would you try it if you can get it over there? Is it a REPLCEMENT for GC since they stopped making it in 2005? Although sometimes replacements are not necessarily the same quality...

 

Why does no one use 10w40? So many of these engines develop piston slap when cold Im suprised no one wants a thicker cold weight oil.

 

Thicker is not always better.
The reason for multi weight oil is cold start up protection.
Oil's advertised ratings can be somewhat misleading.
M1 0 w 40 can be a thick or thicker than some 10 w 40's out there.
There are alot more numbers to look @ than the viscosity advertised on the bottle.

Same weight labled bottles are not really the same thicknesses through out all the oil companies out there.
The true rating your looking @ are the HTHS #'s. (high temperture high sheer)
If you look at the oil out there they are usually made for a specific application.
Most all MFG's have standard for oils to be an approved oil.
This is aside from North American standards of API & ILSAC.
That & the European standards of ACEA.
Both of those are industry standards for their perspective regions.
Aisan's dont really care lol...

GM alone has quite a few MFG approved oil forumula's.
GM 6094M
GM 4718M
LL-A-25
LL-B-25 (diesel)
GEOS-A / DEXOS 1 (GDI applications)
GEOS-B / DEXOS 2 (newer diesels)

Now as for GC 0 w 30, most run it because it tests well in used oil analysis for LSX engines.
The 0 w 40 M1 does well too.
These oils are made specifically for the European market vehicles.
It seems the general concensus is LSX motors like a HTHS number around 12 to 13 @ 100 cST.
That is definately on the thick side. Also that is an oil spec'd out to these standards & MFG's;

API SN/SM/SL/SJ
ACEA A3/B3, A3/B4
Mercedes Benz -Approval 229.3
Mercedes Benz -Approval 229.5
OPEL Long Life Service Fill GM-LL-A-025
OPEL Diesel Service Fill GM-LL-B-025
BMW LONGLIFE OIL 01
VW 502 00
VW 505 00
PORSCHE A40
Chrysler MS-10725
Chrysler MS-10850
SAAB
FIAT FIAT 9.55535 – M2
FIAT FIAT 9.55525 – N2
FIAT FIAT 9.55535 – Z2
API CF

But for sure a 10 weight is thicker cold, will resist flowing more & can cause more problems @ certain ambient temps.
This is why all the OEM MFG's have been requiring lighter oil weights in their engines.
Cold/start up protection.
Now look up the product rating for the oils your looking at.
Just for example M1;
0w40 has a HTHS # of 13.5 @ 100cST
Vicosity index is 185
10w40 M1;
HTHS 14.71 @ 100 cST
Viscosity index 160

They are very close # wise.
The 0 weight has the cold start protection advantage here though.


Actually if your up for a really long read this truely explains todays oils & their ratings.
http://www.bobistheoilguy.com/motor-oil-101/
Need to read & research oils & importantly how you use the engine & take ambient (cold start) in account.
There is alot to read up on & understand to start to grasp the complex amounts of various grades of oils out there & they're proper uses.
There is no perfect oil for all.

 

^^^ I will agree with everything. I use amsoil 0w30 SSO, UOA always test good and the amsoil sso 0w30 is on the thicker side of a 30 weight which I notice LS engines like.

 

 

 

Dont know if there's any truth to it, but Amsoil is post to be the one of the only pure synthetics out there.
Most others have a componet of base crude in it somehow.

 

Thanks for the extra info! Some synthetics like Amsoil (I think) are group 5 whereas Mobil are group 3. The higher "group" # is a pure synthetic with no non synthetic base AFAIK from reading some oil articles. Specifically my info came from the lawsuit of Castrol VS Mobil when Mobil stopped using "pure" synthetic base stocks (much cheaper, easier to produce) and Castrol argued their oil was no longer synthetic. The court concluded that Mobil had manipulated the base stocks enough to qualify as synthetic. Castrol, in order to remain profitable and compete in the lower priced synthetic market started blending with these non syn base stocks. This is part of the reason Amsoil, Redline etc are almost 2X the price of the others. Are they 2X better? Don't know, but it is more expensive due to its' makeup. Now, is the new Castrol Syntec 0w30 German made as good as the "old" GC?

 

If I remember correctly the Amsoil sso is a Ester base oil also think Redline oil is a Group 5 oil and is also a great pure syn oil. The only reason I use a 0w30 is because it has great pumpability at start up.

 

I have a VW R32. I buy my oil and parts from ECS tuning (great place). They stock German oil and then some.

 

The numbers & specs of the 0w30 castrol looks good & the same as before.
Not sure if it exactly the same formulation but the nunbers pretty much do.