Ford Recommends 5w50 Now?

[GT Pony]

Yep. I am comparing the too. Same Principle most definitely apply. Intake / compression / power /exhaust strokes, oiling, fuel delivery, all the same. Point being is that the more precision in tolerances your engine has, the lower viscosity engine oil you can use. Hence the 0w5 weight oil they use. Fuel diluted as well. 40/50 viscosity oils are for like .030+ bearing clearances, supercharger application where extreme pressure in put on the first 2 main bearings, pressure put on the compression and oil rings, yada yada. 5 weight isn't the cause of wear in f1 engines, extremely tight, accurate clearances are. So I wouldn't worry about the 5w20 in our engines where tolerances replaces precision.

The clincher is what is the max oil temperature and the oil's viscosity at that temperature. The thinner oil you use, the more temperature control you'll need in order to keep the oil from becoming too thin, which causes the MOFT becoming too thin and possibly go to zero (point of metal-to-metal contact).

Any idea what max oil temperatures these Indy engines see and what's the Kinematic Viscosity of that 0W-5 oil at those temperatures?

What bearing clearances are these Indy (and NASCAR too) engines running on rod and crankshaft bearings? Are they tighter than 0.0011?

The rod to crankshaft bearing clearance is specified to be 0.0011 to 0.0027 inch on the Coyote. Pretty sure the same basic clearance spec is called out for the Roadrunner (Boss 302) and Voodoo (GT350) engines. Yet Ford specifies 5W-50 for those engines. Also, when Roush (or anyone else) puts a supercharger on a Coyote they specify 5W-50 but they don't go in and modify the crankshaft or rods in order to be larger journal bearing clearances.

Also keep in mind that the MOFT is also a function of engine RPM, and since those race engines are operating at max RPM most of their life they can get away with thinner oil because running at high RPM helps increase the MOFT in the bearings. On a side note, this is why you don't want to "lug" an engine ... because low RPM kills the MOFT and increases the possibility of metal-to-metal contact in the bearings. It's better for your bearings to rev instead of "lug".

Fact is, the tighter the bearing clearance the less potential the hydrodynamic oil film will have to provide an adequate oil film thickness to keep the parts completely separated. See the attached graph which shows that no matter what the bearing clearance is, a thicker oil will result in more MOFT. The thinner oil (0W20) in the graph shows the MOFT falls off at clearances above about 0.003 inch. Any oil viscosity between those two curves will fall in between them on the graph

The MOFT is the only thing that keeps parts separated. Once the MOFT goes to zero then metal-to-metal contact and wear occurs, and then it's the anti-wear additives that have to take over to minimize the contact wear. Could be those race engines also use some pretty crazy anti-wear additives to help reduce enough wear to get them through the race. I'm betting those engines show some pretty good wear after a race or two, because othewide they wouldn't be rebuilding them.

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[Bullit69]

So then? Which oil we going with boys? New Hellcats use 5w-40…..

 

[AvalancheSVT]

so the manual says use a certain oil for track days. to me that says, if you rip it often run that and run the other if you're just cruising a lot, but ford's been saying use 5w30 for like 20 years on these modular engines.

if thicker oil would hurt your engine at ANY point it would be when it was new BTW

 

[br_an]

Hell yeah

 

[Bullitt0819]

...
ford's been saying use 5w30 for like 20 years on these modular engines.
...

Reference? The OM in my 4.6L '08 Bullitt spec'd Motorcraft 5W-20--yes, it's a Modular engine--and that's what I put in it exclusively. It was a just a DD, but it was running strong with 124K miles when I traded it in on my '19 Bullitt (used a qt. about every 6K miles).

I too considered a thicker oil, like the 10W-30 I had cases of on the shelf, but found out later that it could cause the plastic timing chain guides to break when the oil didn't get to the top end quick enough on cold starts.

https://www.amsoil.com/lookup/auto-and-light-truck/2008/ford/mustang/4-6l-8-cyl-engine-code-h-h/

 

[AvalancheSVT]

this debate has been raging and ford has gone back and forth for literally decades

https://www.svtperformance.com/threads/5w20-vs-5w30.635141/
https://www.modularfords.com/threads/98-cobra-oil-suggestions.78284/
https://www.corral.net/threads/mobil-1-not-what-its-stacked-up-to-be.257074/page-2

manual says do X for track days just do X all the time.

 

[Bullitt0819]

"Ford originally specified a 5W30 motor oil for the engine. They soon found this caused oil consumption and possible catalytic converter problems. This caused a change in the specification to a 5W20 or a 5W20 synthetic blend. It is also believed the lower viscosity oil can travel to the timing chain tensioners more quickly. The oil filter they designed for the engine also has a specific anti drain-back valve and for good reason. "

http://www.agcoauto.com/content/news/p2_articleid/115

But, you know better than Ford, I guess.

 

[AvalancheSVT]

But, you know better than Ford, I guess.

 

[shogun32]

http://www.agcoauto.com/content/news/p2_articleid/115

But, you know better than Ford, I guess.

Ford modular engineers are complete total retards. You not only never use plastic, you don't design an ear that is so obviously weak it'll snap off if you just look at it wrong. And if you're stupid enough to do that you don't also fail to support the guide on the backside so it cant move.

And you also never use a timing chain that is clearly way too long. But the first mistake was using oil pressure as your only mechanism to provide tension. The piston must be a ratchet that oil pressure is used to advance a tooth.

So yes you can make a case for only certain oils and filters to not have breakage. But what should happen is you take these so called engineers out to the woodshed and beat the shit out of them for being so obviously morons.

But seems Detroit is full of people who shouldn't be allowed to engineer themselves out of a paper bag.

 

[GT Pony]

Reference? The OM in my 4.6L '08 Bullitt spec'd Motorcraft 5W-20--yes, it's a Modular engine--and that's what I put in it exclusively. It was a just a DD, but it was running strong with 124K miles when I traded it in on my '19 Bullitt (used a qt. about every 6K miles).

I too considered a thicker oil, like the 10W-30 I had cases of on the shelf, but found out later that it could cause the plastic timing chain guides to break when the oil didn't get to the top end quick enough on cold starts.

https://www.amsoil.com/lookup/auto-and-light-truck/2008/ford/mustang/4-6l-8-cyl-engine-code-h-h/

A 10W in California isn't going to "not get to the top end fast enough on cold starts". Besides ... the oil is forced to the top end by the oil pump. Where did you hear that claim?

 

[GT Pony]

"Ford originally specified a 5W30 motor oil for the engine. They soon found this caused oil consumption and possible catalytic converter problems. This caused a change in the specification to a 5W20 or a 5W20 synthetic blend. It is also believed the lower viscosity oil can travel to the timing chain tensioners more quickly. The oil filter they designed for the engine also has a specific anti drain-back valve and for good reason. "

http://www.agcoauto.com/content/news/p2_articleid/115

But, you know better than Ford, I guess.

And Ford has also went back to 5W-30 in the Coyote. Ford also specified 5W-30 for the Coyotes in Australia. Ford also specified their Motorcraft full synthetic as an option in the OM. Don't believe some off-beat website information on oil. If you really want to learn about motor oil, go hang out on 'bobistheoilguy' chat board.

 

[K4fxd]

https://performanceparts.ford.com/download/instructionsheets/FordInstShtM-6007-A50NA.pdf

That's basically a stock coyote and Ford recommends 5w50

Max Oil Temperature 280° F
Engine Oil (8.0 qts.) Motorcraft SAE 5W-50 Full Synthetic
XO-5W50-QGT or equivalent

 

[Ole Texan]

That is a 2011 engine. 11 to 1 compression, not the same as a Gen3. Maybe that has something to do with recommended oil, I don’t know.

 

[K4fxd]

The gen 3 has the same bearing clearances.

 

[Bullit69]

I really just posted for shits and giggles, and this thread started rolling again….

For what it’s worth, for this hot summer heat I’ll be using some Castrol 5w-40 and taking it on a road trip.

Some tuners I know recommend 5w-50 for hard driven or FBO Stangs. Ford recommends 5w-50 for supercharged applications. So consider your operating conditions and apply your oil weight accordingly.
For this hot summer heat and long trip I decided some 5w-40. We could go in circles all day or visit bobtheoilguy, those guys loooovvve oil threads.

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