Houckster

The oil I use is a 5W50 oil, not 20W50. And I always get better mileage than the EPA estimate that's derived from a car using 5W20 oil since that's what Ford recommends and they test with the oil they recommend. This was true with both Focus' and the Ranger. 5W20 oil provides an almost unmeasureable improvement in fuel-efficiency on the street. What 5W20 saves in reduced pumping losses is more than compensated for by decreased friction between moving parts when the engine has reached normal operating temperature. At this temperature, a 5W20 oil has an effective viscosity of seven, that's not enough to prevent some metal-to-metal contact. My conclusions are based on practical experience over the last seven years.

I have joined this board because I am seriously considering the Fusion as a replacement for my Ranger once the Fusion has all the features I want to see. Nothing starts a flame war like a discussion about oils. Still I thought I would venture an alternative opinion. Ford recommends a 5W20 oil. I don't think it's the best oil possible and I would change immediately upon taking delivery of any Fusion I purchase. 5W20 is a compromise lubricant and no compromise is necessary. Also I would be surprised that Ford's semi-synthetic and full-synthetic oils are "synthetic" in the true sense. Most likely their version of a synthetic lubricant is a Group III petroleum. This is not what most people consider a real synthetic lubricant. As noted by many, the viscosity of the lubricant is oriented towards reducing wear at start-up. It does this by compromising wear resistance at normal operating temperature. As an additional measure, the 5W20 oil is formulated for additional durability in the sense that it maintains its like-new properties for a longer length of time. The oil reflects Ford's expectation that the oil will thicken somewhat as it ages, especially with the longer intervals that OEMs are recommending these days. My thoughts are based on my experience with a Ford Focus for which 5W20 was recommended plus a Focus SVT and Ford Ranger for which 5W30 was the recommendation. At 1300 miles, I changed to a 5W50 true synthetic oil in the Focus. I then drove the car as normal for the next 18K miles without a change. During that time, I consumed about 9.5 ounces of lubricant that, with subsequent experience, was more than I should have anticipated. Nevertheless, not once did the car give any indication of a problem. The engine started easily summer and winter and I always got at least 2-3 MPG better than the EPA estimate around town and on the expressways. At 18K I traded for an SVT because the Focus was simply underpowered. I installed the same lubricant in the SVT at 550 miles and owned it for about 22K miles. I never changed the oil and it always started up fine and got better mileage than the EPA estimate. Oil consumption was about half of what it was on the first Focus leading me to believe that the first miles on a new engine are critical in terms of maintaining the tight tolerances that keep an engine efficient and clean. I might still have that car now had it not been one of the worst rattletraps I was ever cursed to buy. A Ranger replaced the Focus and I've had that for 42K miles. I installed the oil in January, 2004 and I've had about 4-6 oz of consumption in that time. Mileage is about 4 MPG above the EPA estimate. I would guess that about 65% of the driving is light city/suburban driving. From this experience, I've concluded that 5W20 isn't necessary and that one can use a high quality true synthetic like the 5W50 oil I've used without problem so far as wear (whether the engine is cold or hot) or mileage is concerned. Finally, it is entirely unnecessary to wait for the engine to "break-in". With the tight tolerances required by our emissions standards, engines are essentially broken-in as they roll out of the factory. There is absolutely no reason Ford couldn't immediately equip their engines with a 5W-40 true synthetic right on the assembly line.