Well 2 mornings i started my truck and i herd a noise kinda like the dreaded timing chain noise but more like a dry start it was there and gone, then it happened again yesterday morning so i figured id change my oil before i jumped to conclusions and thinking i was screwed and had to do the whole timing change job. So this morning i started the truck and the dry start tick was gone thank god lol now i bought my truck second hand with 123k on it, it has 134k almost on it now and i got to thinking about starting to use 5w40 full syn once its time for another change due to engine mileage and with the turbos being partially oil cooled and under constant heat figured it would help with thermal breakdown of the oil and fuel dilution. I live in south florida so is the any reason why i should not use 5w40 in my little ecoboost?