Sounds like you DO take care of the cars. Long oil changes supported by UOA results doesn't constitute lack of care.

I'm curious; which Mobil1 do you use? I've been hearing disparaging comments about all except 0w-40. "They" say that only 0w-40 is from PAO base stock any more. Other weights are hydro-cracked. Just wondering if you know anything about that. Cant find anything useful on Mobil's website (surprise).

 

For the vehicles in question, yes, I was using 0W-40.

 

I ran a couple of oil changes on our Chrysler T&C using Mobil 1 0w20. Stock weight is 5w20 and got good results. Couple more miles per gal, ran quiet, but used 1/2 qt in 5000 miles.
Next change in the Honda I plan on using Mobil 1 5w30.