I have a 2002 Ford F150 V8 4.6 Litre. It says on the oil cap to fill with 5w 20. But why would a toyota which is almost the same size engine run on 10W 30.

So my question, can I change / should I change my oil type (i use high mileage penzoil synthetic) to 10W 30 or is it 5W 20 for a reason!

 

Why do you not trust the engineers that built the truck. They recommend 5-20 due to the close tolerances and the need for oil to reach tight places quickly.

 

'Cause your Ford is not a Toyota...

Is there a reason you think you need to run thicker oil??

Good luck!

Mitch

 

The "size" of the engine has nothing to do with oil recommendations.

 

And the fact you're comparing what Ford recommends to what's used in a Toyota is leading you astray! Apples and oranges brotha!

 

Close in size maybe, but almost the same engine as a Toyota? Not even close, at all. 5w 20 it is, and for a reason.

 

Ditto all- 5w20. Period.

 

Hi.

As is typically the case, this has been discussed in-depth at an Expert level, already:

First read this ( from post # 11 onward ): https://www.f150online.com/forums/v8...-oil-type.html

Then for the actual testing, read this: https://www.f150online.com/forums/v8...hlight=rotella

The answer may surprise you...


MGD

 

The 3V engine in the second thread is a totally different animal than your 4.6. You can use 5W30 if you want, but I wouldn't recommend anything heavier.

 

Oh, Horsefeathers, lol.

It's a Ford modular - and has more similarities than differences apart for valvetrain control, heads and electronics and displacement. Same architecture, same tolerances, same materials.

The point here is, it's also simpler as it isn't burdened by a VCT system, which is the one of the main reasons a 5w-20 is spec'd in the first place.

So it follows that, if a 5.4L 3V shows no ill effects from running 10w-30, as documented in Jim's testing, (except for extreme cold starts as noted), then a 4.6L 2V would at least fare similarly, if not better.

OP - yer engine won't summarily self-destruct if 10w-30 were to sneak in there - in the summer months, at any rate.

However, 5w-20 IS readily available even in Canuckistan, and it's not at a premium in relation to other oils. Even Costco sell it. There is simply no reason not to just use what the factory recommends. Life's far too short to waste time second-guessing yer oil choice.

good luck!


MGD

 

10w30 and 10w40 in a 3v is a bandaid for the crappy phaser system.