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What weight oil do you use?

sholxgt

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Motorcraft is just fine, not sure what your issue is with it.
My issue was, when I sent Motorcraft full synthetic off for analysis, it had not maintained viscosity at all for a 5,000 mile drain interval. Might be OK for shorter drain intervals, but 5,000 miles isn't asking that much out of a full synthetic.
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sdskinner73

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My issue was, when I sent Motorcraft full synthetic off for analysis, it had not maintained viscosity at all for a 5,000 mile drain interval. Might be OK for shorter drain intervals, but 5,000 miles isn't asking that much out of a full synthetic.
5K is pretty poor I’d say. Manual says normal interval is 7-10K. I refuse to believe 10k is safe lol
 

engineermike

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Basically all of the dual grade oils lose viscosity with use, some worse than others. Better base oils perform better in this regard. Motorcraft seems to be one of the worst, mobil1 fsx2 being not great but I’m not sure about the newer supercar version. I’ve found redline to maintain viscosity the best but it also starts out as nearly a 5w60 so it has more headroom to lose from and it’s expensive. I bet Mercury marine 25w50 maintains the best but when cold it’s pretty thick.
 

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My issue was, when I sent Motorcraft full synthetic off for analysis, it had not maintained viscosity at all for a 5,000 mile drain interval. Might be OK for shorter drain intervals, but 5,000 miles isn't asking that much out of a full synthetic.
What kind of miles were these? Any track time in the mix?
 

sholxgt

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5K is pretty poor I’d say. Manual says normal interval is 7-10K. I refuse to believe 10k is safe lol
The oil itself would probably be OK if it weren't for the fuel dilution. 10k Mile change intervals is probably fine in a 2000 Honda Accord or something like that, but I wouldn't consider it with anything that has Direct Injection.
What kind of miles were these? Any track time in the mix?
That was in my 2013 Lincoln MKS 3.5EB. Just a street car that ran 12.60's. I changed to Driven Racing DI30 and the test results were a million times better. I'm sure I could have changed to just about any quality oil though and had good results.
 

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sdskinner73

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The oil itself would probably be OK if it weren't for the fuel dilution. 10k Mile change intervals is probably fine in a 2000 Honda Accord or something like that, but I wouldn't consider it with anything that has Direct Injection.


That was in my 2013 Lincoln MKS 3.5EB. Just a street car that ran 12.60's. I changed to Driven Racing DI30 and the test results were a million times better. I'm sure I could have changed to just about any quality oil though and had good results.
I refuse to believe it is correct, but that is what the manual says in my 18. Was sticking around 7-7500 at most with pennzoil. Going e85 in the next few days, so dropping those down to 5K max.
 

engineermike

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Another thing to consider is that any euro a3/b4 rated oil is specifically designed for high performance engine protection…unlike us api oils that prioritize emissions and fuel economy. The a3/b4 oils are required to have a higher hths, higher zddp concentration, and higher tbn, among other things. As such, the lowest sae grade that can meet the spec is 5w30. Castrol makes a 5w30 euro a3/b4 that works very well if you’re not wanting to take the plunge all the way to a 40 or 50, but want additional protection from a high performance oil.
 

NHMach1

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I recently used 5w50 Mobil one Supercar changing from Motorcraft, pretty good deal on it. Only have about 100 miles on the oil but will see what it looks like when I change oil next time. From my Dad who was a Ford mechanic his whole life, the 5w50 gives extra protection, just let it warm up a bit more.
 

NHMach1

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With my E85 tune it shifts almost near 8k so I’d rather have something a little thicker in there, just my .02
 

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The oil itself would probably be OK if it weren't for the fuel dilution. 10k Mile change intervals is probably fine in a 2000 Honda Accord or something like that, but I wouldn't consider it with anything that has Direct Injection.


That was in my 2013 Lincoln MKS 3.5EB. Just a street car that ran 12.60's. I changed to Driven Racing DI30 and the test results were a million times better. I'm sure I could have changed to just about any quality oil though and had good results.
Fuel dilution plus twin turbo engine I imagine would be really hard on the oil. I think that oil will last longer in the Coyote than on the 3.5 EB.
 

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sholxgt

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Fuel dilution plus twin turbo engine I imagine would be really hard on the oil. I think that oil will last longer in the Coyote than on the 3.5 EB.
Maybe, but I see no good reason to use Motorcraft. There are significantly better oil options that don't cost more. Or, you can spend a few bucks more and get a really good oil.
 

qwiknotch

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Vortech V3 JT on E85, daily driver.
Mobil 1 5w40 euro, change it every 3k miles
 

Trace

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Mobil 1 in 5w40 Euro for mine
 

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5w20 is used by the manufacturer for EPA and optimum fuel efficiency. I changed to 5w30 mobile 1 full synthetic with Ceratec, with no issues I have 88k with a ESS g3. FYI so you can make your own decision look at oil geek on you tube
Look into that btw, there was a video put out awhile back that showed ceratec was a snakeoil/ bad for the engine. Haven't run it since because the results more than spoke for themselves.
 

momalle1

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For my Mustang GT 5.0, I'm using 5W30 just because I'm already buying Motorcraft oil in the 5 qt jugs for my other two Fords with Ecoboosts and buying four of them fills all of the vehicles.
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