hi all its time for my oil change and just by chance im just about to turn 24,000 miles on my 2006 GMC 1500 4.3..my ?? is i want to go to syn oil and i always here about leaks if you dont do it from new is it to late to change it to mobile 1 since it is still under warrenty for another year and 12,000 miles they should take care of the leaks right ????