When maintaining your 2008 Mazda CX-9, the first step is addressing the engine lubrication system. The 3.7-liter V6 engine requires a 5W-20 viscosity grade for optimal performance across various temperatures. The oil capacity for a full change with filter replacement is 5.5 quarts. Choosing the right AMSOIL Signature Series Motor Oil is crucial because the synthetic formulation resists breakdown, reduces oil consumption, and protects critical components like the turbochargers, which the CX-9’s engine architecture manages efficiently. For the oil filter, the AMSOIL Oil Filter EAO34 is the specific recommendation, though the WIX XP Oil Filter or the WIX Oil Filter are also excellent choices for this application. The 5.5-quart capacity ensures that the engine is adequately lubricated without risking overfilling, which can cause foaming and reduced efficiency.
Transmission and Drivetrain Lubrication
The automatic transmission in the 2008 CX-9, specifically the 6-speed AW6AEL, plays a vital role in the vehicle’s smooth handling and fuel efficiency. This transmission benefits significantly from synthetic fluids that can handle high thermal loads, particularly if the vehicle is used for towing or hauling heavy loads in urban or mountainous environments. AMSOIL recommends a total fill of 7.4 quarts for this transmission system. Using a premium synthetic transmission fluid like the Signature Series Multi-Vehicle ATF ensures that the fluid remains fluid in sub-zero temperatures while providing a reserve of protection during heavy use. For those seeking a cost-effective solution, the OE Multi-Vehicle Synthetic ATF offers similar protection against wear and sludge while promoting smooth, shudder-free shifts. Both products help maintain the integrity of the seals and valves within the transmission, extending the service life of this critical component.
In addition to the transmission, the CX-9 features a transfer case and a rear differential that require specific gear lubricants to operate quietly and efficiently. The transfer case holds approximately 1.1 pints and requires a GL-5 rated lubricant. The AMSOIL SEVERE GEAR® 75W-140 100% Synthetic Gear Lube is an excellent choice for this application, offering advanced protection against wear and controlling thermal runaway. For the rear differential, which holds 2.1 pints of lubricant, the AMSOIL SEVERE GEAR® 80W-90 100% Synthetic Gear Lube is highly recommended. It provides long oil and seal life while containing friction modifiers beneficial for limited-slip applications. Alternatively, the SEVERE GEAR® 75W-90 and SEVERE GEAR® 75W-110 viscosities offer versatile protection for different driving conditions and wear levels.
Coolant, Brakes, and Other Fluids
Proper cooling system maintenance is essential for preserving the engine’s longevity. The 2008 Mazda CX-9 requires 11.7 quarts of antifreeze for a complete system flush with single fan control. AMSOIL offers two distinct options: the Passenger Car & Light Truck Antifreeze & Coolant, which is a pre-mixed 50/50 ethylene glycol formulation, and the Propylene Glycol Antifreeze and Engine Coolant. The latter is a non-toxic alternative that provides up to 150,000 miles or 5 years of protection. Both formulations are free of phosphates, nitrites, and silicates, ensuring compatibility with all cooling system metals and hoses.
Braking safety is paramount, and the CX-9 utilizes hydraulic DOT 3 and DOT 4 100% Synthetic Brake Fluid. AMSOIL’s brake fluid offers stable viscosity over a wide temperature range, ensuring excellent ABS and traction-control responsiveness. Additionally, the power steering system in this vehicle operates on DEXRON-III Automatic Transmission Fluid, meaning the Signature Series Multi-Vehicle ATF or the OE Multi-Vehicle ATF can effectively serve as a power steering fluid, providing smooth operation and protection against wear.
Additional Maintenance and Performance Enhancers
For owners looking to enhance fuel system performance, the AMSOIL P.i.® Performance Improver Gasoline Additive is highly effective. This additive restores up to 14% horsepower and cleans GDI fuel injectors back to 100% flow rate after just one tank of fuel. It helps prevent carbon rap and controls pre-ignition knock, which is particularly beneficial for the Mazda’s engine management system. The product is compatible with capless fuel systems and allows for reduced need for higher-octane fuel. For seasonal storage, the AMSOIL Gasoline Stabilizer helps keep fuel fresh for up to 12 months, protecting against varnish and gum buildup while fighting ethanol corrosion. During long periods of inactivity, the AMSOIL Engine Fogging Oil provides a protective coating on internal engine components to prevent rust.
About the Vehicle
The 2008 Mazda CX-9 represents a significant milestone in the brand’s history as one of the first three-row midsize crossovers to offer a powerful V6 engine. Introduced in 2007 as a 2008 model, it was built on the same platform as the Mazda6 sedan but designed to carry seven passengers comfortably. Under the hood, the 3.7-liter Grand Touring V6 engine delivers a strong horsepower range that rivals many compact SUVs of its era, making it a versatile choice for families and adventurers alike. The vehicle’s design philosophy emphasized a blend of sporty handling and practical utility, a trait that Mazda enthusiasts continue to appreciate today. With its spacious interior and robust construction, the CX-9 has established a reputation for reliability and driving dynamics. It occupies a unique market position as a midsize crossover that prioritizes a engaging driving experience without sacrificing the practicality required for daily family transport.