Hey guys,

Just some extra info… Regarding the OCI’s, your Mustang’s message center will alert you when an oil change is required based on your driving habits. It can be up to a year or up to 10,000 miles. You can click the SETUP button to see how much oil life you have remaining. This information can be viewed in your Owner's Manual on page 322 using this link: (https://www.flmowner.com/servlet/Con...OwnerGuidePage) and select your make & year then select OWNER GUIDE 3RD PRINTING. Now, regarding the oil, Synthetic oil is fine, as long as it meets the SAE requirements. However, if you switch to synthetic oil you can not switch back to regular.

Deysha

 

Untrue. You can change back and forth at any time.

 

I honestly don't care about the myth of switching from synthetic back to conventional. I will always run a true group IV synthetic from Amsoil in my engines.

 

 

Well, finally got the AMSOIL the other day. Will be doing the oild change sometime over the weekend. Had to end up becoming a preffered member and have it shipped. No Dealers close and the warehouse is only open M - F and my schedule does not allow me to go that far through the week. Either way, I got it! I'm good with the way I had to get it! and, by tomorrow the Mustang with have AMSOIL running through her veins!

 

Can't switch back to regular oil....wow a ford "tech" giving wrong advice. Imagine that. I suggest you have a nice long chat with beast on that issue. This is exactly how bad info gets passed around. If that were the case then motorcraft synthetic blend wouldn't even exist if the 2 weren't compatible. WTF.

 

I too call total BS on this claim. Exactly why is switching from true synth back to plain old dinosaur oil so bad?

Take the question to your FoMoCo engineers and ask them exactly why this would be true. I want to hear the professional opinion of a licensed practicing PE exactly why going from true synth to dino oil is destructive to the engine.

 

Every time someone says you cant switch they never give a reason why. I switch all the time and the motor is fine.

 

It's the age old myth about PAO base stocks swelling rubber seals in an engine. Amazing how age old problems, that were solved years ago by the use of Esters (and other additives), still lingers around today.

Switching would make no difference, but again.....I don't care about the myth, since I will never use a petroleum based lubricant.

 

Since most synthetic motor oils on the market today, including Motorcraft oils, are just highly refined petroleum oils (Group III), why wouldn't they be compatible with regular lesser refined petroleum oils and allow you to switch back and forth?