I'm completely confused by this thread. The sides that are being mentioned, we're talking about the sides of the dipstick itself?

How could it possibly be showing minimum on one side, and maximum on the other side of it, only an 1/8" away?. I wonder what a cross section of where the dipstick measuring spot would be... Is it sitting on a 45 degree angle when fully inserted or something?

 

It collects on the inside of the tube the dip stick goes through...

Hrmf - should be enough. Don't look at me. I vouch for my procedure and mine alone - including taking the dipstick out of the engine for a few minutes when warm. Other lengths I follow to ensure I get consistent readings now including only reading the oil in spots I've checked to be level by putting the car in neutral with the handbrake off. If it rolls, don't check it there.

I devised my procedure after getting my car, noting that nearly everyone else with an AP1 complained about oil loss and I couldn't see very much loss when faithfully checking my oil at every fill up. Instead of believing I had some kind of miracle AP1 I decided to run on the hypothesis that my readings could be wrong. Sure enough, after I used my new procedure to measure the oil the level was frustratingly low. That was some 20,000 miles ago and nothing's happened sense but it sure made me pissed off at the time.

 

Thats what I mean - always take the low side cuz the "high" side is obviously getting the oil on it from elsewhere.

For a 1/8 (if that much..) thick dipstick to show a 1/8" difference between high/low, it'd have to be going in at a 45 degree angle! (ignoring all the surface tension/capillary effects)

check the low side, its the true side.

 

checking the oil cold will be different than checking it when it is hot, you will find the hot reading will read higher than a cold reading.

 

Wait, what? A cold reading should be higher, as all of the oil in the head should have drained to the pan.

 

I'm not totally sure why but I've tried checking it cold in the morning and then hot later in the day and the hot reading was higher. When you read it hot you still wait a few minutes for oil to drip back into the pan, hot oil drips into the pan pretty quickly so you don't get a lot more oil dripping back by letting it sit overnight. Oil also changes properties as it heats up, it gets thinner the hotter it gets, and it likely expands in volume with heat. I haven't seen any technical explanation of this but it's just my best guess based on different readings that I've tried to take on my car.