a lot of over the road truckers liked mystic years ago, now blended by Citgo. i see no 75-140 in US site but in Canada, but lots of options that may be better as 75-140 is quite "thick" in colder weather! my 2011 fronty SV Dana OE was semi syn 75-140 but the Dana web suggested 75-90 real synthetic + i used Redlines quality lubes in all my drivetrain + netted 3 mpg. i only haul a little so a lighter lube is safe when its real synthetic IMO. there are 75-110 as well!