That is correct, Ford recommended not driving the GT500 below 40* because of the tires. Changing the tires to a lesser-performance all-season tire that cannot handle the vehicle's performance capabilities will create an unsafe condition; in addition, I also believe the oil that must be used for it was designed to be operated above 40* due to the high-performance nature of this vehicle.
Most Shelby owners store their car during the winter months anyway....why is this even a topic?
Do you have any proof or data to support your claim that Amsoil users "noticed more engine response and efficiency..." and better mpg than using the Ford recommended Motorcraft oil?
Sure do....come on over to SVT Performance and poll some of the 5W-50 Red Line users about their switch to a true synthetic 10W-40. They will tell you the same story, as they are the ones that came to me saying i was right.
While I give you credit for running your own tests and sharing with us on the different brand motor oils, I believe that you are out of line for saying that we should not "rely" on Ford for telling us what oil is best for their car and for throwing Ford engineers under the bus. After all, they are your own tests for which you are interpreting the results of those tests on the basis of selling Amsoil oil for which you are a salesman for. And again, after all, remember that Ford designed and manufacured the car itself. So yes, I will trust Ford for letting me know which oil would be best for the car that they designed.
When it comes to a base line recommendation for a lubricant that will suffice in the car and allow for sufficient operation, sure...Ford knows exactly what they are doing. Since they are offering a lubricant that is only formulated for 3 cars on the planet, one of which has NOTHING in common with the other two, sounds like another profit margin to me. It would have been just as effective to suggest another grade of lubricant that was easy to find off the shelf. Motorcraft 5W-50 is an average formulation, and isn't anything special. The UOA chart proves that alone.
Saying they are "your own tests" is far from accurate. These UOAs have been collected from many different vehicles other than my own. Here is your second fault assumption....you assume that I only endorse Amsoil. That is untrue. I support the use of ANY true synthetic lubricant that is 10W-40 in the Shelby.....Red Line, Royal Purple, Amsoil....even Mobil 1 0W-40.
MC full-synthetic motor oil "Designed, engineered and recommended for use in the Ford GT and Shelby GT500..."
another successful profit maneuver by Ford.
It is a no-brainer to actually put the correct weight of oil in an engine especially when the manufacturer recommends it and manufactures its own oil for it. Do you put the recommended weight oil in your lawnmower? Why would you think the GT500 is worth any less? I don't believe that using an incorrect weight of Amsoil product would benefit any of us. I'm listening to what Ford recommends and not some unknown Amsoil salesman.
This is the quote that is entertaining me the most out of them all.
This is what you are actually saying to me....."It's correct to use a 5W-50 lubricant that is sold and endorsed by Ford because they say so. I will completely ignore the fact that is shears to a very heavy 30 grade/very light 40 grade lubricant in 1,500 to 2,000 miles....because I believe that it's always going to remain a 50 grade lubricant. I also love to be charged a premium price for a highly refined petroleum base stock with heavy amounts of viscosity improver polymers that wear out so fast....why did I even waste my time using their cheap lubricant in the first place...because Ford say they want to sell THEIR oil."
I also love how you feel a true synthetic 10W-40 is an incorrect weight for this car. Guess what Royal Purple highly recommends for the GT500....yep...10W-40. I bet you think that the "10W" lubricant will be more viscous @ 32*F compared to "5W" Motorcraft lubricant. Wrong again....SAE numbers are very misleading. True synthetic 10W-40 lubricants are lighter @ 32*F compared to Motorcraft 5W-50. While MC 5W-50 shears after 2,000 miles....it's very close to the same viscosity as a true synthetic 10W-40. Guess what, this means less start up wear compared to Motorcraft 5W-50.
I will say this over and over and over and over....those of you who still insist to use Motorcraft 5W-50 compared to a true synthetic 10W-40 are fools.
Edited by UnleashedBeast, 25 September 2011 - 05:17 PM.