I like synthetic oils and in the past ran M1 10-30, but last change put in M1 15-50....I run the jeep hard in the summer....long trips and some extended idle....so is it ok to use or too thick?
sounds like I have more of a lifter tick on start up though....I'm at about 148,000 miles...have run synthetic since I purchaced the jeep with 59,000 on it...