I am thinking of switching to synthetic on my 94 Dakota with V6. I have been running either 15/40 rotella T for a while now and kendall before that. I just ordered some auto rx to do on the next oil change. Afterwards I was thinking of switching to Mobil 1 synthetic. What does everyone think?? I have no oil leaks or am not burning any oil now. So I don't want to after switching either obviously, that is my only worry.. I've had a couple of oil tests done and always come back pretty good. Thanks for any input..