Here's my first analysis, for background the first change was at 5k and about every 10k after that, the first I did myself with Pennzoil and a factory filter then the next three were Jeep Wave changes with the dealer using Shell Rotella T6 with factory filters. Next two I did myself with Shell Rotella T6 with a Doc's filter then a Carquest Premium filter. So this analysis is Shell Rotella T6 and a Carquest filter with about 5700 miles on the oil. I changed to Castol Edge Euro this change with a ECOGUARD filter, I'm thinking about going 8k this time and see how the Castrol holds up. So what the consensus on my report and with the Rotella T6 being low SAPS should I consider going back?