I went to Nissan for the oil change and tire rotation this morning. I mentioned to the service advisor writing up the service request about the oil being red and if they would check that. He said no one ever asked for that before. He went out to my car with me and looked at the dipstick and agreed it was red. When the car was brought into the service bay, the service advisor went in and spoke to the mechanic and they both checked the oil on the dipstick and another mechanic also came over to look at it. Then the first mechanic put the car up on the lift and went about his business of changing the oil and filter and rotating the tires. I saw him checking every thing underneath the front end of the car. He put on a new Nissan filter, new crush washer on the drain plug and then lowered the car and put in 5 quarts of Mobil 1 0w-20 that I requested. He checked all the other fluids and topped up the washer fluid and he also checked and adjusted the air pressure in the tires. Lastly he plugged the diagnostic computer into the car's port and checked that. When they were finished, the service advisor told me everything was okay with the car, no leaks and that the diagnostics test showed everything ok. He asked if that was still the initial oil fill and I told him it was replaced with the Castrol Magnatec 0w-20 at 1650 miles and that it was crystal clear when it went in. He said they agreed the oil color was just changing as it progressed through the interval. He said he wasn't familiar with the Castrol Magnatec oil but said there could be some kind of additive in the oil causing the red color. He also said to monitor this oil to see how the oil color progresses during the interval. Not a bad service for $71.54......$59.95 for the Mobil 1 oil change and tire rotation, $1.00 for the crush washer and then tax and oil disposal fee.