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c6z mobil1 or royal purple?

11954 Views 21 Replies 13 Participants Last post by  Likarok
I am undecided what to run in my 08 z06 when I do my first oil change. the dealer did one at 3k when I bought the car the next one will be coming up soon.

I daily drive it but I also drive extremely aggresively and drag race it in the spring/summer/fall months

my friend swears by Royal Purple , however, I had mobil1 in quite a few cars including my srt-10 viper with no issues.


HELP ME !!!??
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I know the oil fill cap on the LS6 has the Mobil1 logo right on the top. Can't remember on the LS7s. I mean, Mobil1 is what GM recommends from the factory, so I would say go with that. But as long as the Royal Purple is a synthetic I wouldn't look for it to really damage the engine.
I stay to what GM reckamends if you have a engin problem at least you had the right oil mobil syn.:thumbsup:
Mobil1

If under warranty, absolutely stay with Mobil1, it'll eliminate all controversies relative to any unforeseen engine failure(s).
I am putting my RP through a Hell test its been over 100 F in Texas and I have been driving in hard traffic and with spirited driving so far. Will take sample of oil real soon and send it to lab. That will tell me ever thing real soon...
I always stay with what's recommended when it comes to viscosity and what's on sale when it comes to brand. So long as the oil you use meets or exceeds the manufacturer's SAE recommendations you'll be fine. I don't waste money because I think one brand is better than another. I have never had an oil related failure in any of the cars I have owned.
Mobil 1 is all the engine protection you will ever need.
cool..got my answer than thanks guys ! :thumbsup:
Check the label I dont think Mobil 1 extended performance meets GM 4718M. I would use the normal Mobil 1.

I will say this, I have a 09 Z06 with low miles. It picked up a mild piston slap sound during warm up. I have since switched to Pennzoil Ultra and after about 1,000 miles the piston slap has disappeared. I also only use Top Tier gasoline now.
Check the label I dont think Mobil 1 extended performance meets GM 4718M. I would use the normal Mobil 1.

I will say this, I have a 09 Z06 with low miles. It picked up a mild piston slap sound during warm up. I have since switched to Pennzoil Ultra and after about 1,000 miles the piston slap has disappeared. I also only use Top Tier gasoline now.
Hmmm. The DVD that came with my 2010 GS, shows someone pouring extended performance into the oil reservoir.
. So long as the oil you use meets or exceeds the manufacturer's SAE recommendations you'll be fine. I don't waste money because I think one brand is better than another. I have never had an oil related failure in any of the cars I have owned.
Totally untrue and nothing but a marketing ploy.
I finally ceasing vendors claiming they meet or exceed GM specs which they never had GM test
GM changed the policy 5 years ago that to maintain warranty the oil had to be on GM's certified list which many of the oils marketed are NOT which means they are also not GM approved.

To deep six all this GM has come out with a new oil standard called dexos and all 2011 cars will have to meet.
Those oils are on the list because they meet GM's SAE recommendations and again, I have never had an oil related failure. Besides, if one does have an oil related failure how is GM going to know what brand is in the car. They'll be able to check weight and viscosity and see that it meets their recommendation but they won't be able to tell if you have Castrol or Sam's in there.
Looking at the list, Royal Purple isn't even on it. I found this explanation on another forum about why Royal Purple isn't on the list.

The oil specified for your Camaro is a 5W-30 that has the API Starburst symbol on it. Also, the oil must meet the GM 6094M performance spec. All Royal Purple motor oils meet or exceed the performance requirements of GM4718M, and GM6094M. The GM 4718M spec is largely an oxidation testing sequence GM began using back in the mid to late 1990’s with the introduction of the C5 Corvette. The new design created some inherent issues with oil cooling. GM needed an oil which could handle higher temperatures for extended periods without a significant increase in the oxidation rate. In 360F Thin Film Oxidation Uptake (TFOUT ASTM D4742) testing, Royal Purple SAE engine oils exceed 1200 minutes before failure. Most synthetics, including GM4718M licensed Mobil 1, will typically reach failure in less than 500 minutes.

The GM 6094M specification is a low temperature cold cranking viscosity. The pumping viscosities specified by GM6094M are shown below. The Royal Purple pumping viscosities are shown for comparison. I have also attached the Royal Purple motor oil data sheet:

GM6094M:

For 0W-XX oils - 30,000 [email protected] -40°C
For 5W-XX oils - 40,000 [email protected] -35°C
For 10W-XX oils - 50,000 [email protected] -30°C

Royal Purple:

For 0W-40 oils - 20,000 [email protected] -40°C
For 5W-20 oils - 22,200 [email protected] -35°C
For 5W-30 oils - 34,800 [email protected] -35°C
For 5W-40 oils – 21,500 [email protected] -35°C
For 10W-30 oils - 18,000 [email protected] -30°C


Higher numbers indicate a thicker, or more viscous fluid. As can easily be seen, Royal Purple motor oils have much better cold flow (lower pumping viscosities) than required.

Even though Royal Purple motor oils meet or exceed the performance requirements of GM 4718M and GM6094M, we cannot list certification because the GM specs also require an API SM rating. We also can not show the API Starburst logo because we do not carry the API SM rating. We have held most of our motor oils back from API SM (most RP SAE motor oils are API SL) because of the lower amount of anti-wear additive allowed in API SM/ILSAC GF-4 oils. The reason for the restriction on anti-wear additive is that certain components of anti-wear additive were shown to cause premature degradation of catalytic converters. OEMs are now mandated by the EPA to warranty the emission system separately from the power train. Rudimentary experimentation showed certain anti-wear additives do in fact degrade catalytic converters; however, the anti-wear additive was applied directly to the core of the cats during the tests. If enough oil is consumed in the combustion chamber (i.e. through poor piston ring seal and/or leaking valve seals), there can be degradation in catalytic converter life. This is not an issue with Royal Purple motor oils used in a mechanically sound engine. The OEMs are willing to trade the longevity of the engine for a possibility of extending the life of the catalytic converters.

We do not agree with reducing anti-wear protection for the engine. For our customers who have vehicles under an OEM warranty that require API-SM rated oils, and have chosen to use Royal Purple API-SL oil, we offer a corporate warranty in the case that engine damage or failure is directly attributable to Royal Purple Oil. I have attached a copy of the warranty for your review.

In summary, Royal Purple motor oils are not currently warranty compliant for your Malibu. If strict warranty compliance is your primary concern, we may not be the best choice. However, if performance and protection are your primary concern, Royal Purple SAE 5W-30 (part #01530, quart bottle) would be an excellent choice. We also offer a retail warranty for our customers under OEM warranty, that use our SL oil instead of the recommended SM oil. Please see attached.


Thanks for choosing Royal Purple and have a great day!


Best Regards,

Christopher Barker
Tech Services
Royal Purple, Inc.
1 Royal Purple Ln.
Porter, TX 77365
281-354-8600
So I still stand by my earlier statement that if the oil meets or exceeds the SAE recommendations of GM then it's ok to use in the car.
Bunk

No vendor in a court of law when your trying to sue GM for voiding your warranty for non approved GM oils can claim or prove they meet or exceed GM internal specs when they have not been tested by GM to even know what the test methods or requirements are or have letters from GM saying they passed the tests and are approved.
API is no longer the sole passing as oil also must be GM certified.

Fostering others to change oils just for your bias of oil vendors is misleading at best as it is their warranty, not yours that would be ripped up

Yes GM can test and know what oil is used and there is public cases of Corvette owners losing warranty over non approved oils and fluids

That content you post is useless as it was with old GM standards and requirements.

If it is not broke, do not F with it and Mobil I use has never been shown to cause any damage even in early C4s when it became GM engine oil standard for Corvettes.
oil leak

i was just wondering, i have a 07 z06 and recently found little dropplets of engine oil, just a tad bit not soo much. i hardly drive the car, it only has about 4700mi. never had a oil change done to it. during the past 3 years i never saw oil leaks, but just this week when i pulled out the car from the garage i found like 2-3 small drops. is this normal? and where do u think its leaking from? thanks!
Where is the position of the drops relative to the car? Plumb up from there.
This is a screen shot from my computer. The window in the middle is from my owner instructional DVD I received with my 2010 GS.

Although it may not be crystal clear, it shows a quart of the Mobil 1 5W30 Extended Performance oil sitting on the engine.



I understand everything being said/discussed, but this is my evidence if anyone at GM questions why I have been using this oil in my LS3.

:buhbye:
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This is a screen shot from my computer. The window in the middle is from my owner instructional DVD I received with my 2010 GS.

Although it may not be crystal clear, it shows a quart of the Mobil 1 5W30 Extended Performance oil sitting on the engine.



I understand everything being said/discussed, but this is my evidence if anyone at GM questions why I have been using this oil in my LS3.

:buhbye:
Personally would consider the printed information in the manual to be of a better reliance, thereby dismissing any controversies that may arise regarding engine related concerns.

However a picture may serve, a manual is still considered a more reliable and proper resource for information, imo.
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