i have a '02 Flareside with the 4.6L and almost 24,000 miles on it. until now i have been running the Amsoil 5W-20 (the API certified oil) since 6,000 miles. i am probably going to switch to the Motorcraft 5W-20 synthetic blend, but i have a question: will there be any negative effects to this? to my knowledge the Amsoil 5W-20 is a full synthetic, while the Motorcraft is just a blend. can switching in any way pose a harm to the engine? any help would be appreciated.

 

well, i heard that if you ran 100% conventional oil for a long time, then switched to synthetics you could have small oil leaks around the gaskets, but I've never seen this actually happen or have evidence to disprove or prove that. As far as the engine itself, changing different brands of oil will not do anything, as long as it's the proper SAE grade for your application. And you stated you are going from full synthetic to a synthetic blend, this is 100% fine as far as I'm concerned. I've heard nothing wrong about going from synthetic to conventional, just the other way around.


Brian

 

mile64, you are correct that the Amzoil you are currently using is a synthetic. But it is not a PAO synthetic but a dino Gp III synthetic. Both are petroleum feedstocks. PAO's are gas to liquid technology while GpIII is liquid and gas to liquid technology. The Amzoil is a fine product for its intended usage. You can change to the MC at any time or any other 5w-20 meeting Fords spec 153-H and most 5w-20 will do this. In the "for what it's worth" column, the blends are turning in lower wear metal numbers and holding up the best in this weight/viscosity.

 

See the Amsoil website link below:

It says "AMSOIL Motor Oils are compatible with all other synthetic or petroleum motor oils.".

http://www.amsoil.com/frequent.htm#compatible

Switching even if you have some Amsoil left in the engine when you go to the Motorcraft should not harm your engine...

 

why are you changing??

 

why switch from Amsoil????????????????????????????????

Amsoil is better than Motorcraft anyday.

 

Really? Are you sure about that??

 

Amzoil XL7500 series is a blend (7500 mile interval)...still better blend than Motorcraft in my opinion. I still don't know why you'd choose to switch to Motorcraft after running Amzoil.

Amzoil 2000 series is a full synthetic. I don't think they make a 5W20 in the 2000 series.

 

Ah, OK..... now I see the disctinction. Thanks

 

Amsoil, great product, but overkill in s treet driven vehicle. I have a lot of fleet guys switching over to the motorcraft 5/20. Seem pretty happy with it, even in old 200,000 mile work trucks. As for that extended oil drain interval, Ill pass. Its common knowledge that cold starts put a lot of unburned fuel into oil- thats a gimme. You can go 7,500 miles on an oil change, but I wouldnt. Stick to what the manufactuer recommends- hes the schmuck thats honoring the warranty. But in the end it all boils down to what makes YOU feel special. Ill stick to my 5-30 Valvoline, at least till the motorcraft comes down a little more in price.

 

http://theoildrop.server101.com/cgi/ultimatebb.cgi

here is a great board about oil, everything you ever wanted to learn.

I see oil causes fights over here as well, thats funny its the same at "the diesel stop"

I product that you may want to consider is www.auto-rx.com I have used it in my stroke and is great stuff, it cleans the motor, stops or prevent oil leaks. (if seal is not damaged) it neutralizes the old oil so you are not "mixing" oil

my oil samples come back cleaner after treating with auto rx, a drop in wear metals always seems to be reported. you can ask about it at the oil message board

XS.D>>>

 

Simple answer *NO.*

You don't even need to do a flush!

 

Only use additives and cleaners as needed, otherwise it's overkill.