Any negatives with moving to GC in my 2500HD? The last owner was a loyal dealership guy and had the trucks oil changed every 5k with bulk GM oil and Delco filter. I bought the truck with 61K on it and its always had a non ecore Delco filter and M1 5w30 since then. It now has 95k on it and since I work at Advance Auto part time, GC has always been waiving to me saying "try me" The truck burns ZERO oil and I run the OLM from 100% to 0%. Since I work less then 1/4 mile from home the OLM usually kicks off at just over 3K in the winter and just over 5K in the summer. Truck only works hard in the summer as it tows non-stop. Winter time it does nothing. Thoughts? should I just stick with the M1 ? I did run a batch of M1 AFE 0-30 and a M1 filter once and it was a tad lower on OP. Would the GC be the same?