WHAT OIL SHOULD I USE?

[demarpaint]

I'm also wondering why they back-spec'd the 3.0 as well. They must be onto something, I mean why bother with an engine that is no longer in production. Next OC my 3.0 Aerostar gets will be with 5W-20 and another A-Rx treatment. I am want to see if there is any improvement in mpg (highly unlikely with the winter blend gas), and if it uses less than 1 qt/3,000 miles, which is now up from 1qt in 3,400 miles.

Frank D

 

[Steelhead]

the 4L Cologne design has been around since the early 80s. all Ford did with the OHC version was to slam a single cam on each head with a jury rigged front/rear chain drive that is too expensive to service
cast iron heads on a cast iron block, as advanced as a Ford flathead V8 with aftermarket OHV heads for hotrodding.

Ford has reached the design and emissions limits of this 25 year old engine design

Ford 4Ls are low rpm engines with large bearings for the HP output that run fine on modern 5w20 oils


Originally Posted By: exranger06

Really, so Ford took the time to back-spec the even more outdated (and ALREADY DISCONTINUED) 3.0 to 5w-20, but they didn't take the time to back-spec the "dead-horse" 4.0?? The pushrod 3.0 was introduced around 1990 and has been exactly the same until it was discontinued this year. The 4.0 SOHC is a much more modern engine that was introduced in 1997, and is still being produced today. If there was any engine not worth Ford's time, it was the 3.0. But they did take the time to back-spec it, and they would have back speced the 4.0 if it was OK to use 5w-20. But it's not OK.

 

[edweather]

I want to thank everyone who responded to my post. Amazing information! I know very little about oil, but am learning more all the time.

I replaced the front crank seal on my '03 Explorer last summer, and it was running like a top and just about to turn 170k when I totalled it 2 weeks ago. I was sick!! So Now I'm starting over with an '06 Explorer. Ford recommended 5w30 conventional for the '03, and 5-30 blend (with 5k oci) for the '06...same engine 4.0L. At this point I'm considering using the recommended oil.