I just purchased a used 2003 Navigator. The manual recommends synthetic oil, but I'm not sure what kind of oil is in the vehicle. Is there a way to determin if the oil is real or synthetic? Should I use real or synthetic?
Thanks in advance!
John

 

Synthetic oil IS real oil. Synthetic is refined to more stringent standards than the "conventional" non synthetic oils. A GOOD synthetic oil will perform better for a longer period of time. There is less "boil off" with synthetic oil. This 'Boil off" condenses out on the inside of your engine. This is not GOOD since 40% of your engines COOLING is done by your oil. Most synthetics have a better additive package than the conventional oils which means they can perform longer. ANY MORE ????

 

regular oil tastes like dinosaurs, synthetic oil tastes like plastic.

 

So...is there a way to identify whether the oil in my truck is synthetic or non synthetic???
Thanks,
John

 

Not without a mass spectrometer. Put the syn in the next go around and be happy with it.

 

I'm surprised your manual says to use synthetic. I'd check again and see if maybe you read something different, or if it recommends using Motorcraft 5W-20 synthetic blend. In any case, it probably says that any oil meeting Ford -929A specs is OK.

 

The main thing is just to change it regularly and the filter. I use syn oil I like the cleaning properties and the flow at cold temperatures. It also is suppose to be better at high temps. This is a question that if 100 people answer it you will most likly get 100 different answers. Don't forget about the other systems in your truck, trans, transfer case, differentials and radiator. They should all get attention. And it doesn't really matter what was used in your truck before it is all compatible.

 

Iwong...you are correct. I read my manual again & it does indeed say Synthetic Blend.
I bought it today at Wallyworld for $10.50 for 5 qts.
John