2007 Dodge Ram 1500 SLT 4wd 5.7 I only put 4000 miles a year. Schedule calls for 5000 or 6 months. I run Mobil 1 Synthetic 5w20. Do you think I still have to change the oil in 6 months
Yes, using synthetic oil doesn’t mean the oil change schedule changes.
Yes, I would change oil spring and fall! With that few miles, your operation falls in the “severe service” category.
You may want to check the oil specified in the operator’s manual. I would certainly not use a 5W20 when towing a trailer, for instance.