The main reasons for it is: easier cold startups, better fuel mileage (basically to meet E.P.A. fuel consumption guidelines) and quicker lubrication to components when cold. Not necessarily in that order. 5W30 is absolutely safe to use, 10W30 is not recomended unless you are in a tropical environment.

 

Mine's an '02 (not a 3v motor) but 5W20 is still recommended. I think '02 was the first year for this big debate. Anyways...5W30 user since day one and 75,000 completely trouble free miles....well, oil related anyways

Not to thread jack, but for you Amsoil fans...they have two different 5W20's and a 0W20. What's the difference between them (other than the obvious viscosity difference in the case of the 0W20) and which one do you guys use?? Wonder if they make a recommendation based on what it's being used for??

**edit** they only have the one 5W20 and the 0W20 but also have two different 5W30's and a 0W30. Wonder if one of the 5W30's is supposed to be better than the other??

If I happened to buy a new truck for some crazy reason, I would most likely switch to a 5W20. Only reason I don't in mine now is I wasn't a Amsoil user when I first got the truck and no one else had a full synthetic 5W20. I think the only thing out at the time was that Motorcraft synthetic blend...which still isn't a bad oil, I'm just a Mobil 1 fan.

 

Assuming that you had anything but Amsoils XL7500 put in the engine, it won't hurt the engine. All of Amsoils products are on the thin side of the viscosity range. The SAE range for a 20 viscosity is 5.60 to 9.29. Most of the Amsoil 5w-30 products will be just over 10.xx. The range for a 30 viscosity is 9.30 to 12.49. You or your engine will never know the difference as most of the 5w-20 oils at temp are 9.xx or right at the top of the viscosity range. Not all 5w-20s are the same viscosity at temp and neither are any of the other viscosities you buy. They fall into a variable range. There is nothing wrong with the oil they put in your truck. You will do no damage to the engine by running it.

Where's Norm when ya need him?

 

It's fine, don't worry about it. Next oil change just put in the 5-20, running a 30w for a bit isn't going to hurt anything.

My 4-stroke sled takes 0-30 oil, that stuff is like water it's so thin. But then again the Yamaha motor's ECU can adjust to run as cold as -40 degrees F, so I suppose that's necessary. My truck would be a popsicle by then.

 

 

Why?? What's up with this oil??

 

There's little difference between 5-20 and 5-30. I've been running motorcraft 5-30 since first oil. No problems.

 

Hey Labnerd...still curious what you meant by your comment about the XL oil???

 

Incorrect oil. The following is straight out of the Amsoil product selection guide as the only suitable Amsoil oils for your engine:

Take it back to the place where you had the job done and ask that they drain it and replace it with one of those 3 correct oils. They sold you the wrong stuff. What they sold you does not meet Ford specs for your engine. Will it hurt it? I doubt it, but why take a chance when you are paying that kind of price for an oil change?

http://www.amsoil.com/scripts/runisa...msoiloaf:index