My wife's office is 2 miles from the house. Her main car is a 2012 Kia Optima 2.0 turbo, and it has had the motor replaced under factory recall. Her backup car is a 2012 Impala 3.6. I've been running Pennzoil Platinum 5-30 full syn in both cars. My dad who is a retired master tech specializing in Euro's, told me that because of the distance I should change her oil every 1500 to 2000 miles no more. He cited direct injection as the main issue due to wash out and to not run E85 for that short run in the Impala. The Impala has 130k and the Kia probably has 50k on the new motor. Now we do drive both cars on trips, so they get exercised, but the main job is office and back, maybe a bank run which is 1/4 mile from office so even worse.
1. What are the opinions here on this idea?
2. Anything further to add such as an additive for the fuel, etc.