HI PAUL; IF YOUR ARE GOING TO USE THE 0-40 SYN, OIL I THINK YOU WOULD BE SAFE AND FINE ON ALL THE PROPERTIES OF THE OIL IN YOUR TRANS , I DO KNOW FOR A FACT FROM WHAT LITTLE TESTING THAT I HAVE DONE WITH THE SYN THAT THE TRANS WILL RUN COOLER BY AS MUCH AS 20-30 DEGREES UNDER A LOAD , AS YOU REMEMBER SYN JUST A FEW YEARS AGO WAS 7-8 DOLLARS A QT AND NO ONE WANTED TO SPEND THAT KIND OF MONEY FOR SERVICE, NOW ESP WITH THE BLENDED , IT ISN,T MUCH MORE THAN THE OLD DINO OIL, MY BROTHER IS A SERVICE AND SHOP FORMAN FOR A LARGE CRAINE CO IN YORBA LINDY CAL, CRAINES ARE SO BIG THEY HAVE TO HAVE CHP ESCORTS, AND THEY WERE HAVING ALL SORTS OF PROBLEMS GOING OVER CAJON PASS OR THE OLD GRAPE VINE CLIMB WITH AXLE SEAL AND TRANS OUPUT SELLS BURNING UP AND OF COURSE LOOSING ALL THEIR LUBE , THEY STARTED CHANGING ALL THE GEAR BOX,S AND THE DIFF, FRT AND REAR TO FULL SYN, BUT THE SAME WEIGHT RATING AND THEIR PROBLEMS COMPLETELY STOPPED WITH THE SEALS BURNING , AND SOME OF THESE THINGS EVEN HAVE DIFF OIL COOLERS , HE SAID IN SOME CASES HE HAS SEEN THE DIFF HOUSING GOING UP CAJON PASS GET SO HOT IT WOULD BURN THE PAINT OFF OF THE DIFF HOUSING, THE SYN STOPPED IT ,, SO WE KNOW THE STUFF WORKS , COURSE THESE THINGS WEIGH IN AT AROUND 80.000 LBS WITH TIRES AS BIG AS OUR TROOPERS . JERRY