I know this for fact that using 10w30 is very hard on the newer engines, at the dealership I go to they have had 6 Trucks come in with problems because using the wrong weight oil instead of the 5w30 like what Ford says to use.The oil won`t flow like the 5w will ,as told by one of their techs. . My F150 is a 97 whick uses the 5w30.
10w30 is a heavier oil than 5w30 is. Like I said this was told to me by a service tech at a local dealership .
I really don`t know that much about oil blends or weights going on what I was told.
Lariat#1

 

I'd like to see them too...

 

The Following is straight from Police Fleet Manager, FORD Oil FAQ:WHY 5W-20 OIL?
" The 5W-20 Oil is a thinner oil with lighter viscosity that creates less drag on the crankshaft, pistons, & Valvetrain. Additionally, the oil pump can pump thinner oil more easily, improving oil circulation. Machined internal parts are more precise than the parts of 20 years ago. This means that clearances between moving parts are smaller & more exact. Thinner oil such as 5W-20 can flow more freely through the engine while still filling the spaces. Thicker oil is harder to push through the spaces between the parts. This causes the oil pump to work harder, which in turn increases oil pressure while simulaneously decreasing oil volume. A lack of oil volume results in a decrease of lubrication & cooling, which may decrease engine part life."
Bottom line: Use what the engineers who designed the motor recommed for maximum engine performance & life!

 

I have a 2003 F150 and the oil cap says to use 5w-20. I get Mobil 1 5w-20 oil from Walmart. It can be hard to find sometimes however!!

 

I've seen no evidence of 20 weight oils turning out UOAs showing increased wear. Most "bad" UOAs are due to fuel contamination, high silicon content, or coolant in the oil. None of those is the fault of the oil itself but rather something entering the oil system that should not at more than a trace amount.

Consider that Ford is not alone in recommending 20 weight oils. Honda, Toyota, Mazda, even the Dodge Hemi calls for a 20 weight. They can't all be drinking the CAFE CoolAid.

 

I agree. Show us.

 

Use whatever engine oil you want. It doesn't matter as long as it meets specs. Use 20W50 if you want to, it won't hurt it. Nobody ever blows up an engine because their oil was too thick. And if you think todays engines' "tighter tolerances" make them run any cleaner/better, you haven't cut your cats off lately! Mine smells like a model T at idle!

 

Thats RIGHT!! I'll toast to that.

 

When are you gonna unbolt that propane tank from the side of your truck?!

 

A NOTE: It's time now to take a new look at oils.
The changes are quite extensive and are coming at a fast rate.
The oil you used last year may not be formulated the same now under the same weight and name.
Look at the API ratings. You may not know what they mean.
For example the anti wear additives are being reduced to very low level even in MC 5w20. This is being done for emissions device life and not for the engine it'self.
Somewhat sad but true.
It takes a whole new look at oils now to get a handle on it.
There is a site called LN Engineering that will give a lot of this info and suggestion on how to get around it.
You will be suprised at what the better oils are now from this stand point.

 

Some customers are reluctant to follow FORD's recommendation to use 5W-20 oil in it's CVPI- ie. Crown Victoria Police Interceptor, engines based on the incorrect assumption that FORD recommends 5W-20 oil in order to increase fuel economy. Any increase in fuel economy is undetectable by the average motorist. Using correct service intervals, along with the correct oil & filter, is the single most important maintenance service you can do to your car.

 

My truck calls for 5w30 so y is everybody telling me to use 5w20?

 

Cause your the genius that started the thread!

 

No not me

 

I looked - theres no TSB . Ford would have a TSB if theres a manual change. I would stick with 5w 30w as long as the manufacturer recommends it. I've went 208,000 miles on my 5.4L so far in my 98 and still have great compresion..