GC 0W30 or Mobil 0w40??

[MrWideTires]

These seem like pretty good oils for me, I can never decide which is better so I use both.
For an engine that likes thicker oils.. (12-14cSt), these provide that, good start-up protection, they are groupIV, and can run for at least 10k miles (though I won't run them that long).
This is in a SpecV that gets driven hard, autocrossed, and road-raced.

Which would be your pick??

 

[y2k345]

How much $ is Mobil 0w40?

 

[MrWideTires]

Originally Posted By: y2k345
How much $ is Mobil 0w40?


$7 a quart for both

 

[buickmaster]

GC 0w30 in my nissan.

 

[JHZR2]

I got great results in my Saab with long drains with the 0w-40, and am getting notably worse fuel economy with gc. My application requires an ACEA A3 long drain oil...

 

[JohnBrowning]

Which ever is cheaper and more available. I prefer M1 0W40 because of the additive package. I like an oil that can last a long long time in use. GC 0W30 is just as good if not better at general wear reduction though it just does not have a long TBN retension so extended drains are out with it!So either will work M1 will keep the engine cleaner though over a life time of use.

 

[Quattro Pete]

Originally Posted By: JohnBrowning
GC 0W30 [...] just does not have a long TBN retension so extended drains are out with it!

Interesting. What do you base this opinion on? The UOAs I've seen don't really support this notion. It also carries the LL01 spec which means it was tested to handle extended drains well.

 

[TurboLuver]

I had the same results as JHZR2. The UOA with M1 0W-40 was great, however I did no do a UOA with the GC 0W-30.

 

[Quattro Pete]

UOA is really not the right tool to judge if one oil is better than the other. With that said, the metal levels (in ppm) were slightly lower with GC compared to M1 0w-40 in my old A4 1.8T, but I only ran these oils up to 5k miles.

 

[Craig in Canada]

My vote would be for GC. M1 0W40 shears very easily and quickly to an 11.x cSt 30 weight and stays there unless you run it a really long time and it begins to thicken up again. I ran M1 0W40 for about 50-60k km and switched to GC. UOAs show it stays in grade better and the engine is MUCH quieter with GC so I'm happier.

 

[fdcg27]

Either oil meets a variety of fairly tough OEM qualifications, so either should be pretty good.
I've used CG in the past, and currently have it in the Subaru.
I have never used the 0W-40 flavor of M1.
I'd say either oil would work well for you.
I am partial to GC, but only because I have used it, and there is the mystique of having to find it, while any Wally's should have the M1.
Also, you can probably get some sort of deal on either oil from time to time, if you keep your eye on the appropriate BITOG forum, Product Rebates etc.

 

[LS2JSTS]

Originally Posted By: Craig in Canada
My vote would be for GC. M1 0W40 shears very easily and quickly to an 11.x cSt 30 weight and stays there unless you run it a really long time and it begins to thicken up again. I ran M1 0W40 for about 50-60k km and switched to GC. UOAs show it stays in grade better and the engine is MUCH quieter with GC so I'm happier.



I completely agree. I switched from M1 to the GC in my Goat and never looked back.

 

[dwendt44]

The Mobil-1 is on sale more often than the GC is.
Some Wal-marts carry the 0W-40, I recall seeing it recently.
AA, AZ and other auto parts stores have deals; five qts.+filter for what ever.