Hi, I have a concern and would like to know use.i have a Truck, F150, FX4, 2007, the manufacturer indicates that I use 5W20 motor oil, I live in Venezuela, a country very hot, with temperatures of 38-40 degrees Celsius, now, I use should this oil 5W20 or 5W50.I use it only acquired full sintetic oil.Thanks.

 

The thinner oil works better at higher ambient temperatures than a thicker oil. Simple physics here. A thinner fluid will absorb more heat, get back to the pan faster and release it faster than a heavier oil. If you can't find the 5w-20 oil meeting Fords specs, the 5w-30 would be the next up but try to stay with an Energy Conserving oil. The EC oils are on the thin side of the viscosity range.
FWIW, I have over 100,000 miles on my 2004 4.6. The temperature around home in the summer time is usually 125F and sometimes more. Sometimes at 10 PM the thermometer is locked up at 125f which is as high as it goes. My wear metals in oil analysis are fine and usually single digit for a 7500 miles OCI.
I hope this translates out for you.

 

What type of oil do you run in your truck?

 

You use should this oil 5W20 only.

Temperatures of 38-40 degrees Celsius is hot for you. Is not hot for your truck.

 

I use either Motorcraft or Pennzoil Yellow Bottle in 5w-20 and change every 7500 miles with analysis. I usually have single digit wear metals and TBN is normally still above 2.0. In the summer time, my truck idles A LOT. If you turn it off, the A/C will never get cool.

 

LANERD, no SYN oil for you?

 

No point in using full synthetic unless you are going for extended drain intervals. There really isn't much difference between a blend and a full these days.

 

I have no problem with people using synthetic as long as they go at least the 7500 mile maximum Ford recomends. The oil is not really the limiting factor in the mileage, it's oil filter. The filter can only stay clean for so long. I don't advise any more than 10K on full synthetic with a quality filter.

On the F150 w/5.4L, I wouldn't use ANY other weight than the 5w-20 since the cam phasers seem to be somewhat finicky as it is. A heavier/thicker oil might clog something in the phasers over time and cause issues.

 

It frequently goes well over 45 C where I live and we all use the 5-20. The oil is formulated to work properly at wide temperature extremes. Modern engines tolerances are so tight, if you run a heavier oil, parts of the engine would be starved for lubrication.

 

Thank you very much to everyone for their assistance.