[rcl4668]

I have been doing oil changes at 2,500 intervals myself and letting the dealer do the changes at 5,000 intervals. So for example, at 2,500 miles I did the oil change, at 5,000 the dealer did it. At about 7,500 I did it and at 10,000 the dealer will do it.

At each oil change, I have noticed that after running the engine to operating temp, shutting off the engine and then waiting 5-10 mins per the owners manual, the oil on the dipstick is a bit above the recommended "MAX" level. Specifically, the oil appears to be not at the bottom of the upper "triangle" (holding the dipstick so that the yellow loop handle is pointing up and the bottom portion of the dipstick is pointing down at the ground) but actually slightly above the top or flat portion of the upper triangle. (I took a picture with my phone but the file size is too large and would not upload to the site.)

When I fill the oil myself, I wind up putting in four full quart bottles of the Motorcraft 5w20 full synthetic and then adding enough oil to go down to the "20" mark on the side of the fifth quart bottle. I would note that after coming back from the dealer oil change the oil level is at the same level.

So my question is: (1) am I and the dealer actually overfilling the engine slightly and (2) if so, am I running the risk of damaging the engine and/or losing some horsepower by doing so?

Thanks for your help.

 

[rcl4668]

God I truly suck at the internet. So I posted the picture of the dipstick to my Facebook page. Here's the link if you can take a moment:


https://www.facebook.com/photo.php?fbid=10203881853541147&l=5f7188e89c

You can see where the oil level goes (right up to the indentation above the MAX level triangle).

 

[Chuckable]

I'm not an engineer, but if you think about how much extra fluid you have to add to move from the level from the bottom to the top of the triangle, you're talking about probably less than 1/6 quart. I don't believe that's enough to cause any harm or any significant loss in HP, much less a few HP.

Most dealers have systems where the oil is pumped from a central location and fed to the individual technician's bay via over head lines, and the amount of oil for an oil change in pre-measured. The technician often just squeezes the handle of the oil gun until the oil stops coming out. It's not always metered perfectly, and so you sometimes end up with a slight overfill.

 

[rcl4668]

Thanks Chuckable, that's my assumption as well. Interestingly, I checked the Fiesta owner's manual and the ST supplement and it does not seem to state how much oil is needed to move the oil level from the "MIN" triangle to the bottom of the "MAX" triangle. In most cars I've owned it takes about 0.8-1.0 quarts but I'd be interested in knowing if people know the actual number for our cars.

 

[Chuckable]

Welcome! I was referring to only the upper triangle itself and not the distance between the lower and upper triangles in total, which I agree typically take between 0.5 and 1.0 quarts.

 

[rcl4668]

No worries, I understood that's what you meant. Anyone out there know exactly how much oil it would take to fill from the MIN level to the MAX level on the dipstick? I would say that I could just eyeball it next time I do an oil change by gradually adding oil but I find the Fiesta dipstick to be a bit hard to read precisely.