Premium Engine Oil & Filters for Malibu M5 / M6 / LT4 Inboard Engines. Keep your boat’s heart running smoothly with our dedicated line of high‑performance engine oil and filters explicitly designed for Malibu M5, M6 and LT4 inboard engines. At Bakes Online, we’ve curated top‑tier brands and components to ensure superior protection, extended engine life, and consistent performance on the water.