I have two 2006 F-150s. A 4X2 XL with 4.6 and about 145,000 very reliable miles, and a 4X4 XLT with a 5.4 and about 98,000 miles. Just bought the 4X4 and know nothing about its maintenance history. It runs and idles smooth and quiet. I have been running Mobil 1 5W20 and a Motorcraft FL820S in the 4X2, and see no reason the change. But I have been reading about the cam phaser issue, and have read in 2 posts that 5W20 oil can increase the possibility of cam phaser failure. They both recommended 5W30, and one person stated the new Fords spec 5W30. Is 5W30 in the 5.4 going to lessen the chance of cam phaser failure, or should I stick with 5W20?

Thanks in advance.

 

After all I've read, I would use 5W30 in the 5.4 3V and if it started getting noisy, I'd switch to 10W40. Or change out the oil pump to a high volume Melling pump.

 

I would stick with the recommended grade unless the oil pressure at idle is too low.

 

You have invoked one of the most controversial questions that exists surrounding our trucks ----(second only to the Trump Russia collusion question). --WHICH DIDN'T HAPPEN-

0/20 0/40 5/20 5/30 10/40 be damned. I doubt there would be much difference in longevity if you use any good quality oil, keep it clean with frequent changes, and filters with good drain back valve, and flushes periodically. The oil filter medium and the fine screens in the VCT Solenoids actually present greater resistance to oil flow with higher viscosity oils (which actually results in greater pressure drop at a given flow volume) and thus can reduce 'pressure' available at the Phasers. Crazy, but there are multiple factors to consider. Of course, thicker oil doesn't 'escape' based on phaser leakage as readily - PERHAPS - helping them work better !!! ?????

I do not know there is an ounce of difference with any of it. I can attest with confidence (as I have thoroughly tested and observed the phasers react to PCM retard / advance commands more quickly with 5w20 that they do with 10w40. But cam position trouble codes are triggered by cams being > 5% from commanded position for more than 5 seconds, and even 20w50 (which I tried) does not make them slow enough to trigger DTCs.

On my 243,000 mile '04 - I am running 5w30 - and feel very comfortable with the way everything is working. Every OTHER oil change, I drop in a quart of motor flush about 50 miles before end of day and let it set over-night. Warm it up the next day (exercise Phasers several times by torquing it up above 1800 RPM in 2nd gear a few times), then do Oil / Filter change with 5w30 Full Syn Mobile 1. Still runs and sounds like new 30k past full timing job.

 

There are two ways to build a base oil. That's the oil before the additive package is put in the formulation, the foundation of the oil, if you will. You can start with a relatively weak base and build it up to your specs or you can start with a base that exceeds the criteria and bring it down to the requirements. Most commonly of the OTC motor oils are built up while the heavy duty oils are brought down. For this reason, I would suggest the next oil in both trucks, look for the Delo 400XLE in 10w-30. What you'll get is a base oil that exceeds the current M1 in stability and you'll get approximately 50% more zinc and phosphorus. Both are great at adding additional lubricity to keep the cam phasers super lubricated. Unless your winter cold startups are under minus 25C, you don't need to worry about lubrication during the winter. The oil good at minus 25C. FWIW, Ford issued a memo to the dealers for Tritons that were noisy. The memo specified the oil at a 15w-40 Heavy Duty oil. You'll also find the performance 5.4 uses a 15w-40 and the specialized performance 5.4 uses a 5w-50. Going to a heavier viscosity oil is not an issue in your Triton engines. So my recommendation- Delo400 XLE 10w-30 oil. Most NAPA stores carry the Delo XLE10w-30.
http://pqiadata.org/ChevronDelo400XLE10W30.html

 

An important "closely related" issue that you didn't touch on is the OIL FILTER. They are part of the equation when considering thicker oil. The filter medium presents a restriction to flow (and therefore pressure drop). At a certain point (??? IDK where), that pressure differential across the filter medium will push the filter bypass valve open ---- circulating "UNFILTERED" oil through the engine.

I only recently became enlightened to the 'filter bypass issue'.
https://www.f150forum.com/f4/oil-fil...record-441939/

 

UH, no, LOL. Talk about over think a scenario. IF you were considering a viscosity change from a 10 to a 90, you MIGHT have a filter that would go into by-pass at cold temps but then the filter would be designed for the heavier fluid. So it's not an issue. Going from a 20 at temp to a 40 at temp is not that much of a viscosity change to have any effect on the by-pass valve on an oil filter regardless of ambient temps. I know this is hard to believe but an elementary school class did not design our oil filters. On a Triton engine, at cold startup, many will hit over 100PSI at the filter but it still does not go into by-pass unless it's already full of particulate, and that's using the recommended 5w-20 oil. The biggest effect the viscosity of the fluid on a filter will be the actual filtration. A thicker fluid has the tendency to hold and push particulates thru the filter media, not around the via the by-pass valve. But the viscosity range must be extreme for this to happen and going form a 20 to a 40 or even a 50 fluid isn't going to do it. By your assertions, the specialized performance 5.4 engine would be running in by-pass 100% of the time since they require a 5w-50 oil using the same filter as the Triton. I can assure you Ford isn't stupid although sometimes they'll do something with their designs that makes you wonder. Rest assured that the oil filters that are speced for any engine are designed to work 100% of the time on the engine in environments that are beyond extreme.
I assume you are aware that the oil pump itself has a relief valve on it. That valve body eliminates fluid pressures that the oil filter can't handle or push it into by-pass under normal hot/cold cycles. Unless there is a major malfunction of the oil pump AND the by-pass valve in the filter, your scenario is near impossible. BUT, I'll also caveat this with I've seen a Mercedes diesel in a car that the oil pump relief valve malfunctioned and blew the filter off of the engine. Talk about a lawsuit from hell!

 

One of my neighbor's retirement job is lawn care. He has a 2004 F150 with the 5.4 bought new and now it has over 140,000 miles on it and it is still quiet. He said he uses 5W40 oil in it.

 

First is true.

Second - MAYBE-, depends on 1). Filter bypass valve relief specification { ~13 to 23 psi} 2). Delta pressure across filter medium, which is a function of [permeability of filter medium], [instant viscosity of oil], [total flow volume through oiling system], [Upper Flow limit imposed by Oil Pump bypass].