What is all the hype about German Castrol?

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445
Location
wv
Can someone explain why this oil is so highly respected? What are its strengths? The more detail you can give the better. I went ahead and put it in my truck and my car (the new gold stuff.) I like to buy ANYTHING made in Germany. But can someone please explain what it is about this stuff that is so good. Does it have any weaknesses?
 
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2,689
Location
South Carolina
GC 0W-30 is a heavy duty, long-life oil that meets many of the more difficult Euro specs. I don't know if I would call it a weakness, but because of its ability to resist shear at high temps and it's viscous nature, it will not be your best alternative for fuel economy, if that is what you are after. There are better choices for that purpose. But for engine protection it is rather stout, especially if your engine calls for one of the Euro specs. As a contrast, Mobil 1 0W-30 will probably return slightly better fuel economy figures, but will not protect or hold up as well in high heat, turbo, DI, type engines. It's made for fuel economy in apps calling for 5/10W-30 API SM.
 
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33,940
Location
Southern NJ
 Originally Posted By: Pablo
It's a good oil. But within a span of just a few years many oils caught up and passed GC. The best deal is the price - you can score GC for Syntec SALE prices!
+1
 
Messages
313
Location
Lugoff, SC
 Originally Posted By: Pablo
It's a good oil. But within a span of just a few years many oils caught up and passed GC. The best deal is the price - you can score GC for Syntec SALE prices!
What oils are better than GC? (Please say Mobil1 0w40 )
 
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47,540
Location
Duvall WA - Pacific NW USA
I don't want this thread to get rhetorical and yeah-yeah. There are more robust oils and there are oils that fit the application with more precision than trying to shoehorn GC into every engine/application.
 
Messages
313
Location
Lugoff, SC
 Originally Posted By: buster
 Quote:
What oils are better than GC? (Please say Mobil1 0w40 )
Well, Amsoil SSO for one. I think M1 0w40 is also.
My issue with Amsoil, Red line, RP and other "specialty" oils is that they are not certified in...anything. Call me nutty, but I like seeing that little API donut on the back of my bottle along with the ACEA A1 notation. But, I can get M1 0w40 for about 4 dollars a quart, where as GC is over 6 for me. I have been thinking about switching back to M1 for a long time because people here seem to love it just as much as GC.
 
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2,044
Location
Toronto-ish, Canada
I switched my BMW from M1 0W40 to GC and it was a positive experience. Less shearing, far less under-hood noise, higher TBN at the end of my intervals. I switched my dad's BMW from the dealer synthetic oil - an ACEA A3/LL-01 5w30 - (he only runs half of the OI OCI) and it was a miracle transformation. At only 80k km it used to sound like a diesel about to die - clattering lifters, bottom end knock at low rpm etc... GC shut almost everything up within 20 seconds. Everything else totally disappeared after a round of ARX. Now at 150k km it purrs. It now gets GC every 10k km or so. M1 also got good UOA results (except for shearing like crazy) but I had three vehicles get noisy on M1 products. I believe it was when the switch to the API SL formulation took place - I forget which of SuperSyn, TriSyn etc... I wasn't as attentive, and never thought to blame the oil (I had been brainwashed into "M1 is the best" at the time) but I noticed a BMW (0w40), Porsche (15W50 red cap) and Acura (5W30) all get noisy with lower frequency cam noise and general under-hood "hash". The second I put anything other than M1 in suddenly all I could hear was alternator and PS pump. I won't be going back to M1 for anything unless there's a darn good reason because of this. The UOAs were fine, but I don't want to put up with the racket when lots of other oils like GC also get good UOAs. Amsoil SSO may be a great oil, but the current posted specs show it being nothing like GC (other than saying 0W30 on the bottle). It's in the 10cSt range, and HTHS down near 3. It's an energy conserving oil, not a high HTHS euro oil. I think Amsoil's only appropriate offering to compare is AFL 5W40. With GC my UOAs are great, my engine sounds great, looks great, and still gets good-enough-for-me fuel economy (36-40mpg on the country highways in a 5-series BMW with wide summer tires). I'm in Canada so I appreciate the 0W part of the rating. If I was in the mid/southern US I'd probably just run a 15W40 HDEO year round. I also use GC in my snowthrower due to its shear- and fuel-resistance while retaining excellent cold properties. GC isn't for everything, particularly not fuel-efficient four cyls like Hondas and Toyotas. For anything requiring ACEA A3 and higher HTHS give it a look - especially if it gets cold where you are. A lot of four cyl owners have said they love the quiet and smooth quality but it robs too much power and fuel economy to be worth running.
 
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JHZR2

Staff member
Messages
44,851
Location
New Jersey
 Originally Posted By: buster
 Quote:
What oils are better than GC? (Please say Mobil1 0w40 )
Well, Amsoil SSO for one. I think M1 0w40 is also.
We shall see soon... In my application, I need an ACEA A3, GM-LL-025-A spec oil. The LL-spec Im sure is fine, and I drive light and gentle, so my real need to usean A3 oil is questionable to some extent. That said, we will soon know how SSO compares to M1 0w-40, and I have GC in there right now too.
 
Messages
39,802
Location
Great Lakes
 Originally Posted By: Craig in Canada
36-40mpg on the country highways in a 5-series BMW with wide summer tires
How do you do that? I can't get better than 30-31 mpg if I take it really easy on the hwy.
 
Messages
313
Location
Lugoff, SC
 Originally Posted By: Quattro Pete
 Originally Posted By: Craig in Canada
36-40mpg on the country highways in a 5-series BMW with wide summer tires
How do you do that? I can't get better than 30-31 mpg if I take it really easy on the hwy.
Sounds like the typical baseless claims I hear daily at work. I had an old man with an S90 (3 liter inline six) claim that he was getting 45MPG because he put a magnet on his fuel filter.
 
Messages
2,044
Location
Toronto-ish, Canada
 Originally Posted By: Quattro Pete
 Originally Posted By: Craig in Canada
36-40mpg on the country highways in a 5-series BMW with wide summer tires
How do you do that? I can't get better than 30-31 mpg if I take it really easy on the hwy.
Dunno. I always get into the 30s (if I'm driving for economy and on summer gas). Up towards 40 isn't possible every time, I think variable fuel properties plays a role here. Maybe this proves the old M52's superiority to the M54 :) Seriously though, do you drive stick or auto? I have stick, and the best economy seem to occur on cooler summer evenings when you don't need the AC or the windows wide open. A lot of M62/TU drivers say they get best economy over 80mph. I've found my M52 is best around 50-60mph and downhill from there. If you're trying to compare Interstate conditions to rural, don't bother. I can get near the upper 30s on interstate-class highways. I run Esso AKI 91 fuel with FP3000 (Esso gives the best performance and fuel economy of the major brands around here in this car), GC, Amsoil MTF or Redline MTL in trans, Redline in the diff, factory sport suspension ride height and alignment, factory style 5s 235/45/17 shod in PS2s running slightly higher pressures than sticker (like 33/35 F/R).
 
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Messages
2,044
Location
Toronto-ish, Canada
 Originally Posted By: KLowD9x
 Originally Posted By: Quattro Pete
 Originally Posted By: Craig in Canada
36-40mpg on the country highways in a 5-series BMW with wide summer tires
How do you do that? I can't get better than 30-31 mpg if I take it really easy on the hwy.
Sounds like the typical baseless claims I hear daily at work. I had an old man with an S90 (3 liter inline six) claim that he was getting 45MPG because he put a magnet on his fuel filter.
Yeah, good old baseless miles driven since the last fill up divded by the fuel needed to fill the tank... Sorry you weren't along see it or check my math.
 
Messages
39,802
Location
Great Lakes
 Originally Posted By: Craig in Canada
Seriously though, do you drive stick or auto? I have stick, and the best economy seem to occur on cooler summer evenings when you don't need the AC or the windows wide open. A lot of M62/TU drivers say they get best economy over 80mph. I've found my M52 is best around 50-60mph and downhill from there. If you're trying to compare Interstate conditions to rural, don't bother. I can get near the upper 30s on interstate-class highways. I run Esso AKI 91 fuel with FP3000 (Esso gives the best performance and fuel economy of the major brands around here in this car), GC, Amsoil MTF or Redline MTL in trans, Redline in the diff, factory sport suspension ride height and alignment, factory style 5s 235/45/17 shod in PS2s running slightly higher pressures than sticker (like 33/35 F/R).
I've got a manual. The mpg I listed is with cruise control set at around 70 mph on an interstate hwy, running Shell 93, GC, RP Synchromax in the tranny, and Redline in the diff. Same factory sport suspension and OEM 17x8 rims with Bridgestone RE960 235/45/17 tires. Considering EPA rates your car at 26 mpg hwy, you're beating it by quite a bit. Just to make sure, we're talking about US gallons, not imperials ones, right? :)
 
Messages
2,044
Location
Toronto-ish, Canada
 Originally Posted By: Quattro Pete
I've got a manual. The mpg I listed is with cruise control set at around 70 mph on an interstate hwy, running Shell 93, GC, RP Synchromax in the tranny, and Redline in the diff. Same factory sport suspension and OEM 17x8 rims with Bridgestone RE960 235/45/17 tires. Considering EPA rates your car at 26 mpg hwy, you're beating it by quite a bit. Just to make sure, we're talking about US gallons, not imperials ones, right? :)
:) Perfectly valid point, made that mistake before.... At 70mph, I would probably be getting the same as you, and I would expect your M54 to be superior to my M52. As I mentioned I find my engine/gearing best in the 80-100kph zone. In these conditions I absolutely recall getting 6.5L/100km or 6.6 several times, which onlineconversion.com states to be just over 36mpg(US). I believe I also managed 6.3 once, that's mid 37 mpg(US). I acknowledge that was up in my "best ever" territory but it was not with a 100kph tailwind coasting downhill or anything like that. The "40" must have been a UK conversion stuck in my head from a while back, I throw myself at the mercy of the thread. If I can't achieve 7.5, something is wrong (bad gas, strong headwind, dragging a piano) and that exceeds 31mpg(US). On an interstate (>70mph) I'd consider 7.0-7.5 typical, so 31-33+. The stretch that generally gets used for mental reference is a vacationing run from one Great Lake to another (Ontario to Huron) on a route that's straight with few stops and not a lot of passing required, but there are hills. I generally do more observing of fuel economy on the way there (west) with prevailing head winds. In day-to-day use, I'm not driving for fuel economy so I'm usually getting 20-24 almost all city. My whole on-topic point about GC was that with this engine I feel good about what I'm achieving which, I'll happily rephrase, "well into the 30s" when I want to. Winter gas is another story
 
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