I recently switched from Motorcraft simi synthetic 5w20 to Mobil 1 5w30 and I think my motor is running cooler. My temp gauge was running slightly right of the normal mark and now it seems the needle stays straight up and will not go any higher unless I really push the revs. I thought it was interesting.

 

Mobil 1 is the way to go

 

I can usually tell when my oil starts to shear as temps rise at the track. Castrol and M1 work better and hold up longer than motorcraft. I have oil analysis to back this up

 

I just changed to 5w-30 Mobil 1 in both of my cars, v6 Mustang and v6 Edge. I noticed both engines are a lot more quiet compared to Motorcraft blend 5w-20.

I'm not trying to start another 'oil war'

 

I used to run Royal Purple synthetic in my GSR. used to beat on that poor motor and it never burned oil even after going 7k in between oil changes.

 

I personally don't like Mobil 1 because back in the day when I used to use it, it made my engines more noisy and I had increased oil consumption. I also had oil analysis done when using it and it came back with increased wear compared to the conventional oil I had been using.

I have not used it since but I guess it probably is better than when I used to use it.

Wayne

 

Mobil1 and most other synthetic motor oils truly aren't 100% synthetic. They are ultra refined. A synthetic motor oil is refined to the point where the larger molecules have been removed leaving behind the smallest of molecules. The large molecules are the ones that cause all of the issues, they cause coking, carbon build up, pre mature wear and of course don't have the lubrication qualities that small molecules do. Small molecules handle heat much better and also handle cold much better

Look at it this way if you had a jar and filled it with course sand, there would be less grains of sand than if you filled the same jar with fine grain sand.

So a quart of synthetic motor oil has lots more molecules due to the smaller size.

This is another reason why that in older engines synthetic oil is prone to leaking vs conventional oil. The small molecules will leak past smaller openings.

So FYI most synthetic oils aren't truly synthetic. They are just ultra refined conventional motor oils.

 

This is true, but I thought Mobil 1 EP (extended performance) was the only true synthetic Mobil 1 carried?

Regardless, I use Amsoil, and had it in Marilyn since day 1 of her first oil change within 300 miles on odo.

AMSOIL FTW.

 

I have always used Valvoline. My Suburban has almost 300K on her and the engine is like brand new. Mobile still uses wax in there oil and it aint going into my car. With the Track Pack Ford Specs 5W 50 Ford Spec C. There is only 3 oils that pass that. Motorcraft till the warranty is over or till more oil company's make the new Spec.

 

Amsoil now makes a 5w-50 that meets fords spec.

http://www.amsoil.com/shop/by-product/motor-oil/gasoline/sae-5w-50-signature-series-100-percent-synthetic-motor-oil/