Well the thing i read on the racing oil is that you have to make sure it meets the GM specs of your car my car required 6094M and the ATL product code is what i use, amsoil says in a passenger car run 12500 or 6 mos. drop the filter topp it off then at 25000 or 1 yr change oil and filter, they gauruntee it to be safe, i am still not sure if i will go that long but i may......i do a lotta easy driving high and city but save the hammering for the weekend........PS im am speaking in Miles above not KM