I did an oil change on the gas station and instead of 4.2 qt. the guy put 6 qt. in. so he ended up draining everytning and then pouring the oil back in. 1.5 qt. was left that he put into original Mobil1 bottles and gave me. here is the thing that i am conserned about: the NEW oil that was out of motor was already black color (like old). i compared it to new bottle of Mobil1 10-30 Syn. oil, and my oil was twice as dark. Is this normal? btw. my motor oil was also Mobil1 10-30 Syn.

 

Oil will darken quickly, but if you pour it in and maybe run the car for a couple of min, and then the new oil is well and truly black and dirty again, well it really shouldn't be.

 

well....the car was running on new oil maybe 5-10 minutes and when the guy at the shop drained it, it was already noticably darker then the new-opened bottle (I checked later side by side)

 

When you drain your oil, some of the dirty oil remains in the engine.
Your fresh oil probably mixed with the dirty oil that remained in your engine, causing the new oil to darken. I'm less concerned about that than I am about the guy pouring the oil back into your engine...although the oil was fresh, I hope the drain pan he used to collect the oil was clean. I think I would have poured the oil thru a coffee filter or something just in case...

 

i did see him cleaning the pan before draining the oil. i'm concerned that he didn't even do the oil change and that's why the oil was black. i was gone at that time, he might've just installed new filter and emptied my bottles. (i heard some machenics do that)

 

Or maybe he didn't replace the oil filter. Did you check to see if it was a new one? The oil filter will hold about 0.5qt of oil. If you don't change it, that will mix with the new oil too.

 

i don't know......the oil filter was the same brand, i don't know if it's new or not. ah.....i''m just gonna have to find some more time and do another oil change. it's just too bad i have to spend another $35-40 bucks on oil again.

 

A 5qt jug of Mobil 1 is $19.xx at Wal-Mart.