Am I nuts to run GC year round?

EmbarkChief · Oct 18, 2004

I read way more than I post in here so bear with me...

Car: 1996 Impala SS
Engine: LT1 V8 (5.7L, 350cu.in.)
Mileage: 145K

Climate: Hotter than **** in summer, mild in Winter, might see below 30 deg 5 times a year.

Oil: GC 0W-30
OCI's: 5K

Sane? A part of me thinks this oil might be a little too thin for summer use, but the again its thicker than than Mobil 1 5w30 that I used to run. Car seems to like it, however I haven't run any used oil analysis yet but now that I've installed the Fumuto drain that might change. Other oils that I've run have been Mobil 1 Truck and SUV and Amsoil 0w30 and 5w30 S2K. It just seems odd to run a 0W oil in the Texas heat... Thoughts?

Pablo · Oct 18, 2004

Probably will be fine. I'd be more tempted to go with a 10W-X though...

lyle · Oct 18, 2004

You're running an SAE 30 weight equivalent in the Texas heat, and the fact that it qualifies for a 0W rating at -30C is a bonus.

Don't worry, feel good for yourself, some of us can't find GC in any of the Autozone stores around here.

JohnnyO · Oct 18, 2004

quote:

Originally posted by EmbarkChief:
It just seems odd to run a 0W oil in the Texas heat... Thoughts?

In Texas heat the viscosity at the high end is what matters.

EmbarkChief · Oct 18, 2004

Thanks for the responses gents. I'm feeling a little better about it now

T-Keith · Oct 18, 2004

Does the GC have alot of VII. The usual reason for moving to a 10w30 rather then a 5 or 0wXX is to decrease the VII and the tenancy to shear. If this has little or no VIIs then why not?

ekpolk · Oct 18, 2004

A couple more things to consider. First, GC shows itself to be a relatively heavy 30 wt oil. In used oil analysis it shows CSt values that are almost to the 40 wt range. So you should expect no problem with it being "too thin."

Second, one might wonder whether a 30 wt oil with a 0w cold rating might have a shear back problem. Again, this does not seem to be an issue with GC. It has a HT/HS (high temp/high shear) rating of at least 3.6. This is why the oil qualifies for the A3 rating.

Finally, I ran GC last summer in my previous car, a Camry V-6, and had outstanding results as shown in a used oil analysis. My home is in Pensacola, but during the week, I work in New Orleans. Our summer climate is about as nasty hot as yours. IMO, GC works great in hot climates.

TomJones76 · Oct 18, 2004

We've never had a single UOA that I saw where GC failed to perform due to high heat or extreme usage.
Someone please contradict me if I'm wrong.

Dr. T · Oct 18, 2004

As long as you don't have consumption it will be fine. However, I think the 5k is too short of an interval with a synthetic. 7.5-10 would be more of what I'd like to see the oil do...

ekpolk · Oct 18, 2004

quote:

Originally posted by Dr. T:
As long as you don't have consumption it will be fine. However, I think the 5k is too short of an interval with a synthetic. 7.5-10 would be more of what I'd like to see the oil do...

I'd agree with this. As with any new-to-your-car oil, you'd want to look for any signs of incompatibility, and oil consupmtion would be an indicator. Try running it for 5k or so, and then sucking a sample out through the dipstick tube (Blackstone has sampling siphon; I have one, it's a great piece of gear). If it looks good then, you can keep running it longer, if not, re-evaluate where you are.

Patman · Oct 18, 2004

I ran GC year round in my LT1 Firebird, and am doing the same in my 98 Corvette as well. It works very well in the summer, as my used oil analysis have proven.

Keep in mind that GC 0w30 is very close to being a 0w40, so it can handle higher oil temps without a problem.

And it definitely works well in the cold of winter too (I see my share of sub 0F mornings here, and my car is parked outside overnight)

uconn1150 · Oct 18, 2004

quote:

Originally posted by Patman:
I ran GC year round in my LT1 Firebird, and am doing the same in my 98 Corvette as well. It works very well in the summer, as my used oil analysis have proven.

Keep in mind that GC 0w30 is very close to being a 0w40, so it can handle higher oil temps without a problem.

And it definitely works well in the cold of winter too (I see my share of sub 0F mornings here, and my car is parked outside overnight)

Patman,

How "close" is the GC to being a 0w-40? I was comparing GC to Mobil 1 0w-40 and saw the difference was 2 pts. How close is the difference?

Thanks

EmbarkChief · Oct 18, 2004

I guess I should have stated in my opening post that my consumption is right around 1/4-1/2 quart per 5k miles. It should also be noted that I drive it like I stole it. I'm not going to run it out any more than 5k till I do a used oil analysis. Seriously, thanks for all the replies.

Gene K · Oct 18, 2004

A 30 Weight is 9.3 cSt minimum @ 100&#176C.

40 Weight begins at 12.5 cSt.

GC (SLX) is 11.9 - 12.3 cSt depending on lot # and who did the VOA. Castrol specification is 12.1 cSt @ 100&#176C.

Mobil 1 is in the 9.7-10.7 range (R excepted) with 0W being the thickest.

Gene

[ October 18, 2004, 05:54 PM: Message edited by: Gene K ]

blupupher · Oct 18, 2004

I posted a similar question a while back and got the same response. It is closer to a 40 weight. We see about the same temps here in Houston as you, and my next change in the Hyundai will be to the Green nectar of the elvish gods. The 0 winter rating does not seem to be an issue like the older broad viscosity oils used to be.
I will see how it runs with it before I start stashing it, I only have 8 qts now (2 oil chnages), but the 2 local AZ have well over 50 bottles on the shelf, and the one by work has some too. I am also going to be doing 7500 mile OCI, which is really a stretch for me. I am an old school 3000k kind of guy, so this will be an experiment in patience for me to. There have been a few who have had decreased oil consumption with the GC if memory serves.

SSDude · Oct 18, 2004

I run GC year round. GC is tough. It can take anything Texas, California, Canada or any other state can throw at it.

2KBMW · Oct 18, 2004

SSDude.

I didn't know we became a U.S.
state.

SSDude · Oct 18, 2004

I did not say that Canada was a U.S. state. However, the last time I checked, Canada was an independent state within the British Commonwealth. Granted Queen Elizabeth II is your head of state. Please read carefully.

2KBMW · Oct 18, 2004

SSDude. I know. I was just kidding.

uconn1150 · Oct 18, 2004

quote:

Originally posted by Gene K:
A 30 Weight is 9.3 cSt minimum @ 100&#176C.

40 Weight begins at 12.5 cSt.

GC (SLX) is 11.9 - 12.3 cSt depending on lot # and who did the VOA. Castrol specification is 12.1 cSt @ 100&#176C.

Mobil 1 is in the 9.7-10.7 range (R excepted) with 0W being the thickest.

Gene

Mobil 1 0w-40
cSt @ 100º C 14.3

So what's the diff between GC & Mobil 1 0w-40?

Thanks!

Am I nuts to run GC year round?

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