Quote:"while not nearly as cold as illinois, here in my neck of va last night, it was 27 degrees with a the wind blowing at 25+ mph. we are right on the coast, so it was the cut right through ya kind of cold. we also got a dusting of snow. i think the wind chill was around 15. using castrol gtx this go round, 5w30 weight. started with no problems at all, about the same as my usual pennzoil 5-30, known for it's good cold temp properties. penzdude"
Your car does not experience wind chill. The outside temp is what the temp is, period. Wind chill is what we feel from the effects of heat loss. Same as a warm day with a cool breeze. Your Jeep 4.0 will do fine on 10-30 year round, but many have shown better wear numbers on a 40 weight. Personally, I run 1 gallon of HDEO 15/40 ((currently trying Tection) with 2 quarts of 5-30 in the summer, and a 50/50 mix in the winter. No issues here right outside of St. Louis, MO, in 130,000.