This going to ruffle some feathers but that is life. First synthetic oil is a great product IF it is used for the applications it is designed for. Second you are not using full synthetic at least I hope not. Full synthetic has no anti rust properties in it. You can put it in a can and leave it outside and the humidity will rust the inside of the bottom of the can right through the synthetic. No synthetic oil is full synthetic even if is says that on the can. The claim as to being full synthetic is nothing but a marketing plow to the uneducated public that sounds like something supernatural. The only way to have anti rust qualities is to have some amount of dino product in the synthetic.
Now, it is your money, but you are just wasting your money using synthetic in a street vehicle. I have been in the petro chemical industry for over 40 years, read and seen the engineering studies and even used it in varying applications and the stuff is a hype with no benefit for standard vehicles. It does make the oil industry lots of money however if they can fool people into using it in their vehicles.
No one has ever gotten any more mileage out of their vehicle because they used the stuff compared to dino oil. The dino oil today is as good as it gets for vehicles as long as you change it at manufacturer recommendations. Synthetic is just a hype when it comes to personal vehicles. It is fine for dragsters that run without radiators and NASCAR that runs high temps and stress and applications like those, and even those can be questionable, but street vehicles and even regular off road ones do not need or benefit from synthetic.
By the way it is NOT slipperier then the dino oil of the same grade. SM dino and SM synthetic are both of the same grade and SM grade to date is the highest grade you can get so neither is more slipperier then the other. The claim that synthetic is slipperier is a false hype. Synthetics are for extreme service and special conditions and unless it is used for what it is intended it never gets to apply its ability and is just a waste of money.
I would challenge anyone who uses it in a family vehicle to prove that they got more mileage out of their vehicle then anyone else has ever gotten compared to when the other person used dino oil. It has NEVER happened! So it is your money, but I suggest that you put it to better use then buying a product that has no benefit to your application. You would do better to buy good oil filters and change the oil at recommended times then using synthetic oil.
All pure nonsense I am afraid.
Synthetic is far better than any regular petroleum based oil, even synthetics like Mobil 1 which is not true synthetic but still way better than petroleum.
Redline and all full synthetic Amsoils are 100% full synthetic.
As far as mileage improvements go I use nothing but Amsoil 0w30 in my wifes Lexus ES300 since the first oil change we did on it and on a trip to Florida where we did 100% hwy miles with cruise control set to 72mph we got 30.89mpg.
On the 3 or 4 tanks of gas that we filled when we first got the car (they had just changed the oil the day we bought it, used from Carmax) so I didn't have the heart to just dump the brand new oil out so let it go about 1000 miles or so.
Anyway we never got over 27mpg with whatever oil they had in there.
So we got 3+mpg better mileage, but we are also using a 0W30 instead of 5W30, not sure how much difference that makes but the car ran noticeably smoother on the synthetic.
So challenge taken.
Now on my Jeep I noticed very little difference in mileage, maybe might have gotten less than 1mpg more if that.
On my 4Runner I have no idea because I ran it straight hwy miles about 200 or so on the drive home and then changed the oil to Amsoil 2 days later so I don't really have a mpg number to go on for it running regular petroleum, plus he supposedly ran "a synthetic blend" in it which is useless and no different than regular petroleum but I don't really know what kind of mileage it got prior to the oil change so nothing to compare it to.
Someone in the "petro chemical" business for 4 days should know better actually.
My old Baja bug would always over heat and I tried everything in the book, put in a deep sump, ran stainless oil lines to the roof and put a large oil cooler under a scoop on the roof, tried every kind of oil.
Nothing helped, it always would over heat if I got on it especially if I took it to the desert or anyplace over 80 degrees.
Friend of mine told me about Amsoil back in 1977, filled it with 20/50 Full synthetic racing oil and BAM, never over heated again, ran smooth as silk and never lost power, ran considerably cooler.
Synthetic is just plain better period.
