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Which oil to use for track days for 2011 Mustang GT?

TheLion70x77

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The original question was, should the OP run higher viscosity oil like 5W-50 when the OE spec was 5W-20. There were a bunch of different answers from different members which is confusing. Some say just use 5W-20 and go with a high end mPAO based oil, other say user a higher viscosity oil like 5W-50 because that's what the Boss 302 uses.

Who is correct or who has the more ideal answer...when I saw this thread I thought to myself, well holy crap, I went through that same ordeal, but instead of relying on other's opinions and anecdotal "logic", I started a research project to find real test data to substantiate or invalid these claims.

What I found was simple, OE low viscosity oil specifications are perfectly fine for street car applications under most street use conditions. But there are different specifications based on the car's design intent. The Boss 302, GT350 and Ford GT are track focused street cars, consequently they are set up that way.

The OP's 2011 is NOT. Hence the 5W-20 oil specification. The question then becomes, what oil is better suited for that car because it is 1. no longer stock and 2. being used in a way it was never intended to be used when Ford designed and tested it.

That means in order to provide the most valid answer possible, we should look at the engine design and it's supporting systems to get a good idea of how oil viscosity impacts their performance. 1. Oil pump pressure and oil volume of flow 2. Rod and Main bearing clearances 3. Cam phasor response 4. Hydraulic Lifter function 5. Oil cooling jet operation.

How do we get that information? Since it's difficult if not impossible to find the exact test data from Ford, the next best thing is to look at published information from Ford's part suppliers which is Borg Warner, Clevite etc. who publish data on their specific systems capabilities. That's all I've done is look at each of those systems to determine the best starting point for the OP, I did it for myself for the very same reason.

That's why if you look at some of my posts, there are document attachments on several of them to back up my claims on how it impacts each system based on OE supplier testing and data which not a single person has provided in this thread...yet we are still debating everyone's opinions on the matter, each which differ. I guess people will do what ever they want regardless of reality. Best of luck with that.

To the OP, look at the data and make a decision for yourself. To the best of my ability, based on all of the information I have collected, 30 and 40 weights are ideal for performance street car applications in the actual base stocks and additive packages available on the market.

The current offerings of 5W-50 from MotorCraft and Mobil 1 (not sure how Lucas Oil's 5W-50 holds up) use sub-par group III base stocks that shear down to 30 and 40 weights which includes loss of HTHS viscosity, so they are more viscous than necessary during street use when new, but do not provide additional protection under track conditions for very long and I've seen UOA's showing them loose up to 36% of their viscosity, which is two grades lower. It's not optimal for your 2011 Non-track pack GT.

Stay with high quality base stocks, mPAO, GTL and Esters. Any of them are highly shear resistant and generally come with great additive packages that promote low friction and wear rates while keeping drag losses to a minimum. Best of luck.
 
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Grant 302

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Apparently you didn't read through Infiniums testing on the loss of HTHS viscosity. I didn't include it because it was here say, I included it because of actual test data on the issues with the use of common viscosity improvers used in motor oils. Yet here we are still debating it...o_O
Actually, I did. I think you should look at this particular chart a little more.

%HTHS vs % KV Loss .png
 

VoodooBoss

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That's why if you look at some of my posts, there are document attachments to back up my claims on how it impacts each system based on OE supplier testing and data which not a single person has provided...yet we are still debating everyone's opinions on the matter, each which differ. I guess people will do what ever they want regardless of reality. Best of luck with that.
So your recommendation is to run 5w50 for your car and the OP?
 

JAJ

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...OE setups are a good starting point, but they are limited to a defined set of criteria of the original design intent, deviate from that and they are no longer valid...
You've got a good point, but you've probably figured out that I'm skeptical about the relevance of a lot of the marketing claims from oil blenders and their component suppliers - additives, base oils, etc. I'm sure the claims of superior lube performance are factual, it's just that they don't matter. A good metaphor for lubrication performance is that of a ship going over a sandbar. If there's enough depth (the lube meets the specification), our ship cruises over the bar with no problem. More depth (that would mean better lube performance than the specification calls for) doesn't make the journey over the sandbar any better. The captain might feel better, but the ship's fine with "good enough".

The reason I hold that view is that the modern car engine is heavily protected by the computer that manages it. When I did the ECU programming on my blown 2011, I gathered just shy of a gigabyte of log data from the engine, running it on the street and multiple times on a road course. I've got hours of data from that engine. Through all this, I learned an enormous amount about how the ECU does its job, and one of the things that stood out was the way that the ECU protects the engine from damage.

This is important because a lot of people who drive spiritedly or take their cars to the track for HPDE believe that they're pushing their engines to the limit, using them in a way that qualifies as "extreme". News flash: they're not.

The guardrails inside the ECU make sure that the engine operates at all times inside the "envelope" that it was designed to operate within. If it gets close to one of the design limits, the ECU will first pull timing or throttle, and if that doesn't keep it inside the envelope, then the ECU goes into "limp mode". The engine ALWAYS stays inside the envelope it was designed to operate within. And, because you're inside the design envelope, you're fine to use the manufacturer's specified lubricant because that's how the manufacturer homologated it. "Superior performance" is about making you feel better - your engine doesn't know the difference.
 
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TMSBOSS

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There is no track warranty for any of the non-track focused car. Why your bothering to even mention you Boss is beyond me because it has nothing to do with the original poster's NON TRACK PACK GT.
Simple logic actually. Ford advises us to run a 5W-50 synthetic oil in our cars to avoid failures of our equipment while also avoiding warranty claims for them. Their reasoning/justification is that the 5w-50 stands up better to heat and offers better protection REGARDLESS who pays for the new engine. They also offer the same advise for all coyote owners. Track your car, run 5W-50. SIMPLE. Sorry I don't have the time to waste on long winded explanations.

After reading through all your posts, what you seem to say is this. Its safest to run 5W-50 in a coyote which sees track use. Dont matter nun which one it is. Also that running a lower numerical weight oil may give you a few HP back at the possible cost of an engine. OK. I guess dat for sum of us simpl folks lesser is betterer. I tend to listen to engineers who track their cars along side us, share in our growth without coming across as a know it all. Could just be me. Sorry Rick I have had enough.
 

TheLion70x77

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Actually, I did. I think you should look at this particular chart a little more.

View attachment 7858
I think you should probably follow your own advice on this one. The scatter plot indicates the majority of 30 and 40 weight oils tested lost around 10% of their HTHS viscosity for ever 20% loss of kinematic viscosity. Heavy clustering is at the top of the trend line (the red line), not the bottom.

So if your trying to provide some cherry picked data point from the graph towards the bottom to avoid admitting the reality that your own 5W-50 UOA shows it's sheared out of grade, it's not going to work out like you think. The ratio remains relatively constant, oils that lost only a small amount of kv also lost only a small amount of HTHS viscosity. Conversely, oils that lost substantial kv, also lost substantial HTHS viscosity. Your UOA is in the SUBSTANTIAL category at 30%! How are we not comprehending this...?

A 2:1 ratio kv/HTHS. At 30% kv viscosity loss of the M1 5W-50 on your own UOA that you provided, is down about 15% HTHS which is an entire grade. It is what it is man. MotorCraft and M1 5W-50's just don't hold up very well and fall out of their grade. In order to get a base oil that isn't uber expensive like an mPAO or Ester, they have to use a Group III with lots of polymers that don't hold up under HTHS conditions. Consequently the polymer chains untangle and your oils viscosity drops as does it's protective film thickness.

Now, it may still be providing ENOUGH protection that it's not causing excessive wear. I'm not suggesting that. I'm only saying it's not idea and there are better solutions.
 
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TheLion70x77

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So your recommendation is to run 5w50 for your car and the OP?
Nope. Why would I want to run an oil formula that can't stay within it's grade specifications...? 5W-50 is an extreme spread, it is the most extreme temperature range requirement and hence why they have to use a lot of polymer viscosity improvers to meet that specification.

Unfortunately due to technology limitations, it's a spec that creates oils in that grade that shear down badly and drop below their grade specifications rather quickly, so it isn't actually providing greater film strength even after short use intervals than one or even two grades lower (I've seen UOA's showing as much as 36% shear losses in kv for both MC and M1 5W-50, putting it in the 5W-30 viscosity range), choices are also very limited and pricey. Grant 302's UOA showed 30%, so his case was not the worst.

So why run an oil that's thicker than it needs to be when new (higher wear rates for normal use cases that many of you use your track cars in), but then shears down (lower protection than the grade requires) when you need it to protect? Why not just run an oil that has the same viscosity all the time as the sheared down 5W-50 if the car is fine on technically failed 5W-50? You get the benefits of lower drag losses, better wear and adequate protection all by using a stay in grade oil. Perhaps I'm more focused on efficiency and the whole picture than most, seeing the reality that your not getting better protection with 5W-50 because of how it drops out of grade and becomes something other than 5W-50 anyway.

I suspect most people will continue running 5W-50 that shears down to 40 and even 30 weight being none-the-wiser because it's what Ford recommends and because it makes them feel good, nice thick oil, must be working well...I can understand using it for warranty purposes, but what about after your warranty expires?

What about Mustangs that are not Boss 302's or GT350's that call for 5W-20 from the factory like mine or the OP's? High quality 30 and 40 weights are more ideal for those applications. I'm not going to argue against warranty reasons for staying with 5W-50 if you have an expensive GT350 that's under warranty even if it's sub-par oil, but in all other cases it's an ineffective viscosity grade and just doesn't make sense.

And I've only been trying to point out your 5W-50 isn't 5W-50 after just a short time, it's just not optimal...I want consistent performance from my engine oil, not oil that changes viscosity dramatically over it's life, which creates changing conditions for engine operation that are not ideal. Some specification don't work out so well because they simply aren't practical to achieve, 5W-50 is one of them.
 
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Grant 302

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I think you should probably follow your own advice on this one. The scatter plot indicates the majority of 30 and 40 weight oils tested lost around 10% of their HTHS viscosity for ever 20% loss of kinematic viscosity. Heavy clustering is at the top of the trend line (the red line), not the bottom.

So if your trying to provide some cherry picked data point from the graph towards the bottom to avoid admitting the reality that your own 5W-50 UOA shows it's sheared out of grade, it's not going to work out like you think. The ratio remains relatively constant, oils that lost only a small amount of kv also lost only a small amount of HTHS viscosity. Conversely, oils that lost substantial kv, also lost substantial HTHS viscosity. Your UOA is in the SUBSTANTIAL category at 30%! How are we not comprehending this...?

A 2:1 ratio kv/HTHS. At 30% kv viscosity loss of the M1 5W-50 on your own UOA that you provided, is down about 15% HTHS which is an entire grade. It is what it is man. MotorCraft and M1 5W-50's just don't hold up very well and fall out of their grade. In order to get a base oil that isn't uber expensive like an mPAO or Ester, they have to use a Group III with lots of polymers that don't hold up under HTHS conditions. Consequently the polymer chains untangle and your oils viscosity drops as does it's protective film thickness.

Now, it may still be providing ENOUGH protection that it's not causing excessive wear. I'm not suggesting that. I'm only saying it's not idea and there are better solutions.
Wow. Now you're really getting loose with the math, like in the past.

What HTHS do you think my used sample is at?

Do the math carefully and the right way, please. It's simple and the number range I get is okay with me.
 
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TymeSlayer

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5W50 is what it is in my Boss. I disagree that Ford goes this route because it's cheaper and fattens their bottom line. Quality and reliability go a long way in sales and thus profitability.
 

BigTaco

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Ok let's try this again, keeping in mind Occam's Razor theory...

What are you running and what do your recommend for the OP?

BTW I'm running 0w40 in mine. :eek:
I think you should probably follow your own advice on this one. The scatter plot indicates the majority of 30 and 40 weight oils tested lost around 10% of their HTHS viscosity for ever 20% loss of kinematic viscosity. Heavy clustering is at the top of the trend line (the red line), not the bottom.

So if your trying to provide some cherry picked data point from the graph towards the bottom to avoid admitting the reality that your own 5W-50 UOA shows it's sheared out of grade, it's not going to work out like you think. The ratio remains relatively constant, oils that lost only a small amount of kv also lost only a small amount of HTHS viscosity. Conversely, oils that lost substantial kv, also lost substantial HTHS viscosity. Your UOA is in the SUBSTANTIAL category at 30%! How are we not comprehending this...?

A 2:1 ratio kv/HTHS. At 30% kv viscosity loss of the M1 5W-50 on your own UOA that you provided, is down about 15% HTHS which is an entire grade. It is what it is man. MotorCraft and M1 5W-50's just don't hold up very well and fall out of their grade. In order to get a base oil that isn't uber expensive like an mPAO or Ester, they have to use a Group III with lots of polymers that don't hold up under HTHS conditions. Consequently the polymer chains untangle and your oils viscosity drops as does it's protective film thickness.

Now, it may still be providing ENOUGH protection that it's not causing excessive wear. I'm not suggesting that. I'm only saying it's not idea and there are better solutions.
is your handle “unleashed beast” on SVTPerformance?
 

JAJ

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Oil is like religion in a lot of ways: it does its work out of sight, the effects are invisible to the untrained eye and those who believe the words of the gurus laid down in the sacred marketing scripts get grumpy in the face of skeptics and non-believers.
 

Red5OH

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FWIW
2011 Mustang GT - Track Package
Owned it since July 2010
152K (kms) - Runs like new; compression is still according to spec; dynos +/- 5 hp/tq from first dyno run in 2010. No out of the ordinary oil consumption during track/autoslalom events (but religiously check before each event)

First year: Motorcraft and Mobil 1 5w20 - 8 Regional Autoslaloms; 2 Time Trial Events and 1 Track School
- driven year round - 2 changes per season

2nd year: Mobil 1 5w30 - Switched it, noticed that I didn't need to top-off my oil monthly as frequently - 8 regional Autoslaloms; 3 Time Trial events
- driven year round - 2 changes per season

3rd year: Spoke to Ford Performance Rep at an annual Mustang event. Referred me to the BOSS 302 Supplemental Manual. Mentioned that 5w50 is recommended for tracked Coyote motors. Same/similar tolerances (apparently)

Mobil 1 5w50 - summer months
Mobil 1 5w30 - winter and spring

4th and 5th year - Same usage and change frequency

6th year - Summer only use begins - 8 Regional Autoslaloms; 3 time trial events; 2 Driving Schools

Mobil 1 5w50 summer months (changed 3 times in the summer)
Mobil 1 5w30 - storage

7th year to today: Summer only use - 8 Regional Autoslaloms; 4 Time Trial events; 2 Driving Schools

Redline 5w50 - summer months (2 changes: Beginning of season; Mid-season)
Mobil 1 5w30 - end of competitive season (2 changes: off-season (Sept-Nov), Storage)
 

PapierTiger#60

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Welcome to TMO!

Ford Racing/Ford Performance recommends 5W-50 for all Coyote engine variants for the track/HPDE. Can't hurt to give them a call if you want to hear it directly from them.

Essentially, 5W-50 will protect the engine better than 5W-20 at high temps and high RPM.

I've been running 5W-50 in my 2011 GT with the Boss cooler and an external oil to air Setrab 925. My Boss is stock except for cooling mods and of course gets 5W-50.

Engines like ours with the oil squirters/piston cooling jets transfer heat loads to the oil very quickly. Heavier weight oils perform better under these high heat loads.

.....

Unrelated, but if you don't have another tune, I do like the Ford Performance ProCal tune for better throttle response for heel-toe blip rev matching.
Just wondering how did you manage to have boss oil cooler and A2A oil cooler at the same time?
 

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