SCORGE

Either oil will do you fine. Simply saying that 30 has worked for me. No chain slap, no noise. Quiet as a mouse. There's a counter-argument to just about everything, but I have no desire to get into another oil argument, as it has been discussed to death.

650NutKase

The US is the only country with this engine that designates the 5w20 spec. Personally, I run a 5w30. I have seen no ill effects with this switch, as the change between those two viscosity at operating temp is nothing that will do harm. Also, most wear done to an engine is at startup, where both are within a 5w range. Modern VII's will make sure that the oil is always the correct viscosity at any given temp.

Long story short:
5w30 wont harm a 5.4 3v, boo boo.

Eric Kleven

I put on about 12k using 5w-40, kept everything running until I could get into the engine.

there's a lot of anecdotal evidence of fleets running everything in 15w-40 and the 3v engines behaving themselves just fine for hundreds of thousands of miles.

Seriously, these engines are NOT picky about oil viscosity. If they were, you wouldn't even be able to get out of the parking lot with a cold engine, and you'd have to have an oil pre-heater to keep it at a precise operating temperature before you could start it.


Once the tensioner seals pop, then things might start to get picky. Viscosity makes a big difference on flow through an orifice, your thinner 20-weight will dump more oil volume through the same leak than a 30 or 40 weight. Pressure is inversely proportional to flow. You do the math on that...

LariatDude

Again where do you guys find the info on what oil type is run in other countries. I've never seen anyone provide proof of that

tcp2

go to shell's oil website for australia and choose a ford falcon with the 3v 5.4l from 2001 onward. Recommended oil is 5w30 or 5w40 for the 3v long before it ever arrived in North America. I ran 0w40 in my 09 and it ran smooth as silk. the number before the "w" indicates cold weather performance. The number after the "w" when it is at 100C or 212F.

And, no, there were no changes to the 3v for North America...just the oil spec.

Smokin04

I agree that most damage (if not the VAST majority) is at startup. The 2nd part of your statement is only correct with up to temp oil. 20wt and 30wt are NOT the same viscosity when cold. Please read as Bob explains it way better than I can:
https://www.bobistheoilguy.com/motor-oil-101/


I concur...but it seems there is a lot of misinformation on this board.


If that's true, why not run the thickest oil possible? Why not run a straight 60wt oil? That would give some great oil pressure. Max protection right?

You are proving my point. A thinner oil will "flow more" through the bleed orifice than a thicker oil would until they reach operating temp (using multi-grade oils like we all do). With this logic (which is correct) the thinner oil would keep more oil in the lash adjuster and flow through the oil filter media or bypass (when cold) than the thicker oil. Thus providing more wear protection on startup.


I'm quite sure that the only way to actually illustrate my point is to tear down 2 engines after 200K miles and compare the two. One with a proper oil and one with a heavier. I'm by no means saying that the engine wouldn't physically operate on a heavier oil...quite the opposite actually (because at temp they're all 5W anyway, in fact a lot of hot rod modular guys are running 0W-20)...I merely saying that the thinner oiled engine will in the majority of cases show LESS wear than the other after several thousand cold-starting events. But to each their own.

Smokin04

That's exactly backwards.

650NutKase

I agree that most damage (if not the VAST majority) is at startup. The 2nd part of your statement is only correct with up to temp oil. 20wt and 30wt are NOT the same viscosity when cold. Please read as Bob explains it way better than I can:
https://www.bobistheoilguy.com/motor-oil-101/

I never said they were the same viscosity. I said the range was still in the 5w bracket.... The main reason I switched over is to stop oil consumption. I was losing about a quart every 3k. Since switching, I am not losing any. This is because the 100c and flash points are typically higher in 30w oils than 20w.

LariatDude

I checked that website. For the Fairmont 5.4 04-05 it calls for 5w-20 as well.

LariatDude

Although AM seeing a lot of the modular 3v V8's calling for 5w-30 and 40. Hmmm that's convincing tbh