I'm willing to bet you got FS 0W40, not ESP X4
Mobil 1 ESP 0w40 in GM LS Engines
- Thread starter LZ0 Bob
- Start date
How does Mobil ESP 0w40 compare to the new formulation of Mobil FS euro 0w40 ?
Mostly SAPS level and the resultant approvals.
I bought my C7 with 58k miles on it and first ran Mobil 1 EP 5w30. Then I went to Mobil 1 FS 0w40, and now it has had Mobil 1 Supercar 0w40. I've never heard a sour note or bad sound of any kind with any of them. I've got a stash of FS 0w40 still, so I will probably run it for each of the next two years before going to some ESP 0w30 that will finish off my Vette stash. I'll probably pick up some more ESP 0w30 to re-supply the stash after that.
My OCI's are once a year, with between 3500 and 5000 miles on each run.
My OCI's are once a year, with between 3500 and 5000 miles on each run.
Why would you use 30 grade oil in an engine spec'd for 40 grade of a supercar like Corvette?
The definition of pressure is actually force per area (ie, lbs/in^2). If the flow circuit is a constant physical configuration (like an oiling system), and the viscosity is constant, then more pressure means more flow is going through the system supplied by a positive displacement oil pump, which is the type of pump engines use. That's why oil pressure goes up with RPM.
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It is not specified for a 40 weight. The 2007 LS2 calls for 5w30 in the specs. I believe it also recommends a higher viscosity for track use, but my Vette never sees the track. And the 40 weight is Dexos R rated, which states it is backward compatible. So either a 30 or 40 are fine in this engine, with the proper Dexos approval.
But how is both 2007 and Corvette C7?
The GM TSB from 2018 states otherwise (last paragraph):
"Mobil 1 dexos2™ 0W-40 released for the 2019 Model Year engines can be used in 2014-2019 Corvettes with the LT1, LT4 and LT5 engines. When tracking the 2019 ZR1, it is required to install Mobil 1 15W-50 oil. Once the event is finished and the vehicle is put back on the road, the Mobil 1 15W-50 needs to be removed and Mobil 1 dexos2 0W-40 added back to the engine."
https://www.corvetteforum.com/forums/attachments/c7-general-discussion-142/mobil-0w40-4607946/18-na-129-0w-40-oil-bulletin-48322800d1644276805#google_vignette
Sorry, typo. My Vette is a 2007 C6. I'm getting old and the 2007 mixes into the C sometimes. Unfortunately, it won't let me go back and edit.
It is in my signature, though. C6 , 2007, LS2.
So thanks for pointing it out.
Getting old sucks.
Not necessarily.
In an engine with a positive displacement lube pump (typically gerotor), oil pressure is neither an indicator of more or less flow per se. Rather, pressure is the dependent variable that is reacting to the independent variable of flow. And what the thing that makes the pressure "dependent" is viscosity. Flow happens first, the viscosity determines the pressure (work) required to have done it.
This persistence of the myth of engines having wildly variable flow is why this thread from @ZeeOSix is becoming one of the most relevant and timeless BITOG threads in recent memory.
FS is still very good, but it has less robust VII compared to whatever they are using now in the ESP 0W line. FS loses more viscosity in KRL test. ESP X4 also starts at a higher HTHS (3.8 cP).
Is ESP X4 believed to be the same formulation as M1 Supercar 0w40?
It's interesting that you cannot find even 1 qt bottles on Amazon.
However, online at Walmart is decently priced—same as FS 0W-40.
I did better with the AutoZone bundle. 5 qts of ESP X4 and an STP XL filter for $36. 3 bundles is good for two oil changes on my Corvette.
Is that online or in-store?
I've done it both ways. I think the last time it was that price was in March. I don't know what their current deal is.
This is s bad analogy for two reasons.....
1. Engines have psi relief valves on the oil pump, and thicker oil is harder to pass thru a filter, than thinner oil. Higher rpm leads to higher pressure as the volume has no where to go..... at least until the pump bypass opens to bleed off the VOLUME.
There’s often a misconception that pumps create pressure. That’s not true. Pumps create flow, and pressure is the result of resistance to that flow.
2. Pick up any garden hose,and turn it on wide open with no restriction at the end. TONS of flow, with no pressure. Now kink the end.. Pressure in the hose goes way up, volume goes way down.
Again, this is not a "definition" of pressure, it's an attempt at an analogy based on your garden hose example below that does not represent how the oiling system in an engine really works. The actual definition of pressure is force per area (ie, lbs/in^2) ... the definition of pressure has nothing to do with flow.
True, but doesn't change the fact that for a spring loaded pressure relief valved PD pump (what your LS has), as the engine RPM increases both the pressure and oil volume going through the oiling system both still increase, but at a much lower rate. LS type oil pumps with a spring loaded pressure relief valve will still increase flow output, but at a slower rate, as they start going into pressure relief as RPM increases - I've posted the pressure and flow graphs of those kind of pumps in various threads - Like this Post.
If the engine oiling system operated like you think, then the oil flow would decrease as engine RPM goes up and engines would be smoking themselves due to lack of oil flow volume. Your oil pressure gauge goes up with increased RPM, which means there is also more oil flow happening along with that increased oil pressure. In your garden hose example, if you increase the water supply pressure then the water flow increases, not decreases like you've stated above.
Yes, pumps create flow and a PD oil pump will literally destroy things down stream if the output flow and associated pressure isn't controlled. But that doesn't mean that increased pressure results in less flow as you stated.
This is the kind of an analogy that builds misconceptions. If an engine oiling systems worked like that, engines would be operating in conditions with lack of lubrication. Every engine increases the oil pressure and associated flow volume as the PD pump RPM increases. So seeing more pressure on the dash gauge means more flow is going through a fixed resistance (with a constant oil viscosity of course), not the other way around like you stated.
In this garden hose example you changed the flow resistance of the system and limited the pressure to a fixed value - ie, the water pressure of the house water system. This would only apply to an oiling system if the pump could only put out a fixed pressure and the oiling system flow resistance started increasing, which doesn't really happen. Trying to correlate an engine oiling system fed by a PD oil pump to a house's water system is misleading.
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Yes.
That, the winter rating, how CAFE affects oil recommendations, what violates a warranty and the size of oil passages.
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