have an '08 F 150 4X4 5.4L with only 40K on the odom, just had the engine oil(Royal Purple 5W-20) analyzed and was told to use a quality fuel additive because of slight fuel dilution.....oil was in for 6 months and only 1850 miles as I was considering going a full year with the synthetic with the low miles but was concerned about the dilution which I found out about on a previous UOA.
any suggestions on a fuel additive for these engines?
thanks

 

I use a quart of lacquer thinner or toluene to 25 gallons of 87 octane fuel. 100:1 mix. adds octane and cleans the fuel system. Sometimes I run undiluted E85 for a change. I can tune to use it. For maintenance I use Amsoil fuel system cleaner.

 

I think the best additive for the Modular Motors would be Chevron's Techron Concentrate, two 12 oz bottles to a full tank every 3K miles or so.

I've not yet pulled any injectors for inspection or replacement but one E250 with the 5.4 has just over 270K miles---seems to work for me.

 

Stupid question here....what good would an additive do to rectify fuel dilution? Does it remove the fuel already in the oil? or does it prevent more from get into the oil? or both?

 

I like Techron but fail to see how that would affect fuel dilution of the oil. I would recommend changing oil far more often, and given your use, I don't think you need purple food coloring in your oil, or even synthetic oil. Motorcraft syn blend is just fine. And do try to drive the engine for a longer trip at least once weekly to cook off fuel and water.

If you can use top tier fuels, your need for a fuel additive should be minimal but I still run Techron thru all our vehicles about twice a year. Costco sells 6 packs of Techron really cheap compared to parts stores selling single bottles. (You can google top tier fuels for brands.)

George

 

Sounds like you need to find out why fuel is in your oil.
There shouldn't be any at all.(minimal amount that a lab shouldn't bring to your attention that is) Additives won't fix that.

 

Your truck is fairly young for this problem. I concur with everything George mentioned above. Barring something like a leaky injector, which would cause dilution, I personally would switch to a good diesel oil for a few oil changes to take advantage of the increased level of detergents. In case your rings are sticking, this may help. Others have used stuff like Marvel Mystery Oil or ATF with varying results but I'm not big on additives (except Techron).