Hi Gary, Blackstone Labs has a comments section on the form that you fill out when sending in your oil sample. You could tell them in that area what your additives were. They also ask pertinent questions in the form such as what type of oil you run, how many miles since last change out, if you added any oil since last change, and some others that I can't remember right now. 13 years in Manteca huh? I've been here 14 years now. From Livermore originally.
Steve K9SL
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1998 2500 Quad Cab, 12V, 5spd, 4x4, HD Transfer Case, 370HP Diamond B Injectors, #4 TST, 16cm2 Housing, AFC Spring Kit, BD Governor Spring Kit and other modifications, Walker Muffler, 285/75-16 BFG AT's, Stainless Steel Tube Steps, Reese Fifth Wheel Hitch, Leather, CD, LSD Dana 80 Rear, 60 Front, Centerforce Dual Friction Clutch, Rancho RS9000 Shocks, Rancho Steering Stabilizer, ATS Exhaust Manifold, Psychotty Air Induction