I just bought an 09 Jeep Liberty with the 3.7L V6. The oil it calls for is 5w-20. The car has 1030 miles on it and I am going to change out the oil. My question is what should I change the oil to? I want to change to synthetic but didn't know if I should wait a little longer or not. My oil choices for synthetic are Pennzoil Platinum or Valvoline Syntec. I don't know which oil would be best for our driving. A mix between frequent short trips (very short trips in stop and go traffic) and longer drives. What are you guys suggestions? Thanks in advance.