I used Amsoil ASL 5-30 since 1k miles in my 2006 GMC 2500HD 6.0L... A friend keeps telling me to use the SSO 0-30... i have 43k miles as of now ... I've never have done a UOA i just trusted amsoil and changed 10k another 10k then 15k ... i do use the eao filters as well.. just wondering how many of you would change to the SSO 30W over the ASL5-30...i live in florida and all roads are flat.. i pull a trailer sometimes with less then 3k in weight... tons most miles are leaving my house 1 mile then hitting interstate and driving 70mph... i just for life of me cannot figure out how chaging to sso would even benefit me....would any of you switch at the next 15k mark?