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What race oil should I be running?

Thanks, but why would Ford spec 5W-50 if 5W-20 would suffice and the only difference is how the tune sets the idle?

I'm running a Mike Rousch 93 octane road course tune during HPDE. In all discussions on various forums, I don't recall seeing anything about oil type being a tune parameter. While most S197s on the track may be Bosses and TPs, I'm sure I'm not the only person that has modified their base GT for the track.

Should this be an issue discussed with a tuner?
I think your make making an assumption hear about why Ford specified 5w50; it was not to make the idle lumpy. It was to provide more protection during highload/high temp conditions.

Oil type is not a “tune” parameter per say. What tuners are doing to adjust spark, fuel, and cam timing are not the same as interpreting how a vvt Phaser will react depending on the oil Viscosity used.
Exp. Type
Exp. Level
5-10 Years
Philly Metro Area
Thanks so much for taking the time to respond.

So the calibration and algorithims to which you referred to in your prior posts relate to the firmware in the VVT phaser. Is there a way to update the firmware or just replace the phaser with one from a Boss/TP?

And I take it that although the Driven FR20 resists shear, all else being equal the 50 part of the 5W50 does in fact provide superior load/temp resistance.

Or as jDee suggests, for 20 minute HPDE sessions, it doesn't matter or is not worth the trade-off in sub-optimum VVT performance?

Grant 302

basic and well known psychic
I had an online chat with Ford Performance tech about what would be the correct oil in an unmodified Gen2 (2015-2017) engine for HPDE type track usage with 20 minute sessions that never sees anything beyond redline. The tech guy said unequivocally 5W-20 that meets the Ford engine oil spec is the right oil for the Gen 2 engine for that type of use. He said basically be guided by what it says on your oil fill cap and mine says 5W-20.

Note keywords here: unmodified, Gen2 (2015-2017), HPDE, 20 minute sessions, never goes beyond redline, oil fill cap, Ford engine oil spec.
IIRC, also the recommendation for only one day of track use. Can't remember if that was in the manual or a TP/PP supplement.

The drag would come from the fact that 15w50 is actually thicker than 5w50. You are 100% corrcet, the both fall within the same range at temp but the two oils (15w50 vs. 5w50) will be one opposite sides of the 50 range? Make sense? BTW, I’m totally nit-picking the difference and the increase of drag would be negligible. I’m just nerdy about oil specs.
It is not a 'fact' that the 15W-50 will be thicker or more viscous than the same brand 5W-50 at operating temps. With enough VIs in the formulation the 5W-50 could actually be thicker. There are certainly variations between brands that would make this statement false.

The Coyote VVT is designed to operate properly independent of varying oil pressure. Unlike most VVTs, that require high oil pressure, the BorgWarner system in the Coyote does not use oil pressure to change the cam timing. The oil is used to create hydrostatic locks that either allow or prevent the cams from moving. Energy from the camshaft rotation and valve spring actuation are used to change cam timing. There is another thread on the board somewhere where I posted how the system operates.

^This. I wouldn't worry about any 'sub-optimal' valve timing issues with oil choice. Especially those with Gen2 style mid-lock phasers.


Anyone with questions should call Ford Performance for info on their specific car. "Official" answers appear to have some variability over time.
This has been some interesting conversation. Thanks everyone for taking the time to comment. I took Grant 302's advice and talked to a Ford Performance tech. He said to absolutely use 5w50 for my application even though my stock engine 2012 track pack GT calls for 5w20. So I'm going to go with a 5w50 which is exactly what everyone told me to do in the beginning haha.


Ancient Racer
Exp. Type
W2W Racing
Exp. Level
20+ Years
5 miles from Mosport
IIRC, also the recommendation for only one day of track use. Can't remember if that was in the manual or a TP/PP supplement.

From page 12 of the '16 owners manual:
In addition, if the vehicle is subjected to
dedicated road course use, we recommend
the following vehicle durability
• Change your axle lubricant and friction
modifier after the initial (first) hour of
high-speed operation; thereafter
change the axle lubricant and friction
modifier every 12 hours (under these
• Change your transmission oil after each
event where your vehicle is subjected
to individual on-track sessions
exceeding 15 minutes.
• Change your engine oil and filter after
each event.>>

I started a spreadsheet where I record the accumulated track time to help with the first two items. The third one is pretty simple.

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