Hello, Im a little confused. What oil weight would a 2000 with a 4.6 should I use. One shop manual stats 5W30 while my other manual is saying 5W20. Does it make a difference? I also live where winters can get really cold. Thanks.

 

I think your engine calls for 5w30 from the factory. I dont think they started using 5w20 till a couple of years later. Look in your owners manual or on the oil filler cap. I think it says on there.

 

I believe Ford created a TSB that says its ok to run 5w20 oil in specific vehicles...

https://www.f150online.com/forums/sh...rd+oil+article

https://www.f150online.com/forums/sh...threadid=77117

http://www.ford-trucks.com/forums/ar...ex.php/t-64387

I am running Amsoil synthetic 5w30 in my 1999 5.4L engine and am very happy with it. It has a very low pour point so it perfect for that minus 40 degree weather.

AMSOIL 5W-30 remains fluid at temperatures as frigid as -60°F (-51°C).

http://www.amsoil.com/products/asl.html

 

The oil issue again...I was told by Ford to use 5w20...That's the weight oil to use...

 

I also live in the great white north (Manitoba) and i have used Motorcraft 5w30 synthetic from day one with no problems at all.My truck is an 02 XTR 4x4 with the 5.4

 

Ford selected 5W20 over 5W30 as it provides a small margin of increased fuel economy without compromising engine protection (at least for the duration of the warranty...).

Consult your owner's manual for the original factory recommendation. You can use either that or the current recommendation, whichever cranks your tractor. Either will do just fine without causing oil-related problems due to viscosity.

Steve

 

For the most part there is little difference between the two. With periodic oil and filter changes your truck and "seat of the pants" dyno probably can't tell a difference. The first number represents the viscosity when cold, the 'w' stands for winter, and the second number is the viscosity when hot. Life is a compromise, it takes more additives to increase the range between the two numbers but the main purpose of oil is for lubrication.

Motorcraft 5w20 is a synthetic blend and in Canada will serve you fine. If you want extended drain intervals you could go to a full synthetic.

In south Texas I run Amsoil 10w30 due to the heat. I recently bought an '05 Escape and just changed the oil at 1k miles using Motorcraft 5w20 but plan on running 10w30 after it reaches 10k miles.

 

Have you ever throught about the oil weight designations?
Ever see 'very many' 5w10, 10w20 oil designations for auto engine use?
These 'spreads' are not wide enough to do much good where a single weight oil would likely do just as well..

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5 weight is thin at cold start to ensure fast flow and lubing to the Bearings and Cams during cold starts, plus easier starting in winter temperatures.
Then as it heats, the viscosity tends to increase toward the higher number for variable weight oils.
The 20 weight designation as opposed to 30 offers less pumping losses and helps fuel mileage a small amount.
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Note the fuel mileage part is prompted by the CAFE standards pushed by the Government, so thinner oil fit the cause in these engines.
As well, in the latest 6 and 8 speed transmissions the effort is huge to reduce friction losses, increase fuel mileage and apply new very thin fluids for the same reasons. Note Ford LV and other new fluid designations.

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Also there is a benefit to less wear on the cam chain tensioners without so much cold oil pressure applied for shorter times..
As well, these motors were built to tighter tolerances than older push rod engines.
You can see the benefits of using 5w20 vs 5w30 over the long term.
The old way of thinking that heavier weight oil protects better is overcome by the tighter tolerances and much improved oils of today over that of the mid 90s and before..
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The above is not applicable to heavey machines where the applications, loading and operating conditions are much different.
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OEM Oils are are formulated based on long term life testing at the mfger's testing lab.
Based on engine oil testing for wear and partial accumulation in the oil.
A part that wears to much is re-engineered with a material change, a design configuration change, an oil formulation change or any combinations of changes until the life expectancy is achieved. This is also is the basis of recommended oil change intervals.
Bottom line is use whichever weight you feel comfortable with.
There are to many who try to discount the recommendations with no knowledge basis for it or listen to other old time opinions.