The more I read and research - the more I come back to the defacto standard of the synthetic oil 5K mile OCI with a good oil filter as being about best if you want to keep a vehicle running past 250K miles .
*First , TBN is not the be all - end all in determining how long you should go with an OCI .
*Next , by 5K miles of mixed driving (majority of what we all do) the oil is getting dirty , more abrasive with deposits , fuel dilution starts climbing , etc. so the oil should be replaced .
*Vehicle manufacturers are in business to sell new vehicles - the 7.5K to 10K mile OCI recommendations are only listed in the OM to get you to 100K miles (in most cases) .
*Castrol EDGE EP and M1 EP stating they can do a 20K OCI is marketing (and dangerous marketing at that) only possibly realistic if you do 100% high way travel ; At most I would run a 6K - 7K mile OCI .
*More vehicles today (and growing) are GDI / Turbo engines where by the 5K Mile OCI protects against fuel dilution and soot (abrasive) to keep levels down to an acceptable level .
*European BMW , Mercedes , etc. OCI's of 10K or more just can't be good for ultimate engine up keep long term unless driven on the German Autobahn full time .
*With previous synthetic oil 6K + OCI's with Sea Foam added last 150 miles - oil would get noticeably darker ; at synthetic oil 5K mile OCI's Sea Foam added last 150 miles showed little oil darkening .
* With a synthetic oil 5K OCI I notice less metal shavings in my plastic oil drain catcher afterwards versus 6K + OCI's .
*Disclaimer* : Your mileage can and will vary from what I have listed - however in modern engines using an approx. 5 qrt. sump I believe the 5K OCI is about the best recipe with a synthetic oil for keeping an engine running well past 250K miles ...
*First , TBN is not the be all - end all in determining how long you should go with an OCI .
*Next , by 5K miles of mixed driving (majority of what we all do) the oil is getting dirty , more abrasive with deposits , fuel dilution starts climbing , etc. so the oil should be replaced .
*Vehicle manufacturers are in business to sell new vehicles - the 7.5K to 10K mile OCI recommendations are only listed in the OM to get you to 100K miles (in most cases) .
*Castrol EDGE EP and M1 EP stating they can do a 20K OCI is marketing (and dangerous marketing at that) only possibly realistic if you do 100% high way travel ; At most I would run a 6K - 7K mile OCI .
*More vehicles today (and growing) are GDI / Turbo engines where by the 5K Mile OCI protects against fuel dilution and soot (abrasive) to keep levels down to an acceptable level .
*European BMW , Mercedes , etc. OCI's of 10K or more just can't be good for ultimate engine up keep long term unless driven on the German Autobahn full time .
*With previous synthetic oil 6K + OCI's with Sea Foam added last 150 miles - oil would get noticeably darker ; at synthetic oil 5K mile OCI's Sea Foam added last 150 miles showed little oil darkening .
* With a synthetic oil 5K OCI I notice less metal shavings in my plastic oil drain catcher afterwards versus 6K + OCI's .
*Disclaimer* : Your mileage can and will vary from what I have listed - however in modern engines using an approx. 5 qrt. sump I believe the 5K OCI is about the best recipe with a synthetic oil for keeping an engine running well past 250K miles ...