Hi everybody, I need your help. I have never been a supporter of mixing oils, but it happened that since 2000 for this or that reason I could not use all quantity of oils I had been purchasing, so finally I accumulated an inventory which either due to emerged with age my natural greediness, or due to not too favorable financial situation it would be pity to throw away cause it's a good amount of money. Last year I used old Motul 300V 5W-40 (2002-2004) and GC 0W-30 (2003-2004) and they worked without some manifested issues. The car is Honda Prelude 2.2 VTEC, oil change capacity including filter is 4.8l, engine full oil capacity is 5.9l, recommended oil grades are from 10W-30 to 20W-50 API SG or SJ. Oil grades like 0W-30 and 5W-30 certified for GF-3, GF-4 and ACEA A1/B1, A5/B5 are allowed for temperatures below 0C only. Given I don't have enough oil of one type I would like to mix oils in a relatively safe way, if today something may be still safe and relative, but even after years of oil study I am still not sure about home blends. So, below is the list of accumulated oils with some brief details: 1. Motul 300V BIO 5W-40 - 4 liters (2002-2004, Ca-Ma package, Moly of unknown type is about 800 ppm, not recommended for mixing with other oils of 300V line) 2. Motul 300V 10W-40 - 2 liters (2003-2004) 3. Motul 300V 15W-60 - 2 liters (2003-2004) 4. Fina First 5W-50, API SJ, CCMC G5/PD2, BMW, Porche - 4 liters (2003, PAO) 5. Shell Helix Ultra AB 5W-30 - 4 liters: 1 liter in API SJ, BMW LL-01/MB229.3 (2000, XHVI/PAO/POE), 2 liters in API SL, BMW LL-01/MB229.5 (2004, XHVI/PAO) + 1 liter API SH, BMW LL-01/MB229.5 (2006, XHVI/PAO - downgraded in API) 6. Unocal 76 Nascar Synthetic 10W-30, API SJ - 2 liters (1999 + 2000, PAO + about 15% POE, special patented AW package) 7. Unocal 76 Pure Synthetic 5W-40, API SJ, ACEA A3/B3, BMW LL-01, MB 229.1, Porche - 1 liter (2001, PAO) 8. Mobil1 15W-50 SuperSyn, API SL, ACEA A3/B4-02 - 1 liter (2005) 9. Elf Synthese 0W-40, API SJ, ACEA A3/B3-98 - 1 liter (2002, PAO) 10. Lexus 0W-20, API SN, GF-5 - 2 liters (2014) Any idea how to mix them in order to avoid eventual additive clash ? Many thanks in advance for your help.