uoa 6.0 ford

Apr 8, 2009
truck 07 ford 6.0 71,660 mi. 5016 mi on oil uoa shell 5w-40 syn, viscosity only 10.6, i'm not impressed, prior to last oc used john deere plus 50 15w-40 and lowest vis at 7500 mi. was 13.2. just coming out of winter and i do alot of short trips & warm-up during winter, may have contributed, but never had this problem with jd. does anyone know if ulsd & fuel additives (jd also) play a role with this severe shearing? i haven't figured out how to scan report yet, but i can say from last uoa that wear metals & additives are very comparable to previous uoa, other than vis being low, iron is only 12 thanks