What's the difference between 4.0L and 4.6L

[marriedmanw]

My question is due to the fact that the 4.0L SOHC suggests 5w-30 for oil, but the 4.6L suggests 5w-20 for oil in my owners manual.

I have the 4.0L SOHC engine in my 02 Explorer, and used the 5w-20 Motorcraft oil since it was on sell. It's still pretty cold in VA and I'll change it again by June anyway, but just wondering why the different oil weights between the two engines?

Thanks

 

[exbass94]

Well, they're two completely different engines, and thus have different oil requirements, simple as that. Ford has back-speced most of its engines for 5w-20, but the 4.0 was one of the very few that was NOT. And I believe that Ford must have had a good reason for it. So I would definitely recommend using 30 weight oils only.

 

[john112deere]

Ford has back-speced most of its engines for 5w-20, but the 4.0 was one of the very few that was NOT. And I believe that Ford must have had a good reason for it. So I would definitely recommend using 30 weight oils only.

I believe all their engines except the SOHC 4.0 now spec 5w-20...though I got that piece of information from the local dealership shortly after I told them that the 4.0 specs 5w-30...and would they please take my truck back and fill it with the spec'd oil?

I've yet to find a "definitive" answer on why they don't spec the 5w-20 (which is desirable because it improves fuel economy slightly), but I've heard a few guesses that it has to do with the hydraulic lifters used in this engine.

 

[Downey]

ones a v6 and ones a v8 lol i couldnt help my self sry

 

[marriedmanw]

Thanks for the replies. I don't think I'd do any harm running 5w-20 this one time before next oil change (let me know if you think differently). Usually, I use the 5w30 motorcraft synethic blend, but the store had the gallon size on sell for the 5w-20. I usually have to change the oil by the date before I ever reach the mileage anyway since I only travel 25 miles a day to commute to work.

 

[wvfarmboy]

be better to put 5w20 in your 4.0 as long as u keep it changed than to put 5w30 in your 4.6 but thats my 2 cents worth

 

[Dweano]

ones a v6 and ones a v8 lol i couldnt help my self sry

Also the difference is .6L...

 

[JohnPi]

Also the difference is .6L...

That's the joke I was thinking of when I saw the OP's original thread title.