X2 To many variables to consider but staying on TOP OF the maintenance aspect is crucial especially when running a tune such as fresh fluids all around such as PTU,RDU,TRANS,COOLANT,TUNEUP,PCV etc and especially at 80k on her and using top tier gas such as Shell,BP,93 octane and would also make certain that all pertaing recalls,updates/revisions have been performed accordingly by the dealer in order to get the most out of it and glad the dealer installed new plugs for ya but need to verify that there properly gapped at 0.030.and BTW make certain to revert back to stock tune anytime a dealer visit is indeed needed. Z