Oil and Maintenance Guide for 2006 Honda TRX400EX 397
Before You Service the Engine
To maintain your 2006 Honda TRX400EX 397, use the correct lubricant and carefully check the level after refilling. Since catalog recommendations may not cover every manufacturer requirement, consult your specific service instructions before adding fluid.
What type of oil does a 2006 Honda TRX400EX 397 take?
The engine-oil viscosity shown for this model is 10W-40. The available oil-product listings include 10W-40 Synthetic ATV/UTV Engine Oil, Formula 4-Stroke Power Sports Synthetic Motor Oil. For a service, choose oil that meets the engine’s actual application requirements, not just a product name.
Does synthetic oil automatically mean an ATV can go longer between oil changes?
Oil change intervals vary based on your engine, operating conditions, and manufacturer requirements. A synthetic product listing does not mean you can extend the service interval for this model.

