How to Change Engine Oil & Filter: 2004-2007 Honda TRX400EX

Changing the engine oil and filter on a Honda 2004 2005 2006 2007 TRX400EX four-wheeler is the process of removing the motor oil and filter and replacing it with another of the same kind. Use these factory recommended service procedures the next time you replace the engine oil and filter.

Recommended Motor Oil

Use Pro Honda HP4 or GN4 (without molybdenum additives) 4-stroke engine oil for United States and Canada models. Use Honda 4-stroke engine oil or equivalent on four-wheeler models designated as Canada models onle. Recommended viscosity; SAE 10W-40.

It should be noted, SAE 10W-40 viscosity should be used when the outside temperature is between 20 to 100+ degrees Fahrenheit. But other oil viscosities can be used. When the average outside temperature is between 20 to 90 degrees Fahrenheit, you can substitute with SAE 10W-30. If the outside average temperature is 50 degrees or below, SAE 5W can be used.

Oil & Filter Change

Be sure to pour new engine oil after you have replaced the oil filter. It is also recommended to allow the vehicle’s engine to warm up so as to ensure the oil fully drains. It also helps for rapid draining.

1. Start the Honda’s engine and let the motor idle for a few minutes.
2. Turn the engine off and remove the oil filler cap.
3. Take off the oil drain bolt and allow the oil to drain.
4. After the oil has drained completely, reinstall the drain bolt, but be sure to replace the sealing washer with a new part.
5. Torque the drain bolt to 25 N·m (2.5 kgf·m, 18 Ibf·ft).
6. Remove the engine oil filter center bolt, spring, cover washer and oil filter.
7. Remove the O-rings from the engine oil filter cover and center bolt.
8. Provide a coating of clean engine oil to the new O-rings and reinstall them into the center bolt and oil filter cover.
9. Install a new engine oil filter.
10. 10.Reinstall the center bolt, cover, spring and washer.
11. 11.You will need to tighten the center bolt while holding the engine oil filter by hand. Torque specifications: 18 N·m (1.8 kgf·m. 13Ibf.ft).
12. 12.Fill the motor with the recommended engine oil previously mentioned. Poor the factory recommended oil into the motor up to the upper level mark on the vehicle’s dipstick.
13. 13.Reinstall the oil filler cap and make sure there are no oil leaks.

Engine Oil Capacity

Use 2.6 liters (2.7 US qt, 2.3 Imp qt) if only the motor oil was changed. Use 2.8 liters (3.0 US qt, 2.5 Imp qt) of engine oil if the oil was drained and filter changed. Use 3.3 liters (3.5 US qt, 2.9 Imp qt) if the motor was completely disassembled. 

It is always recommended to use a factory repair manual when performing service, maintenance or repairs. Downloadable factory manuals can be downloaded instantly from this site.

Application: 2004 2005 2006 2007 Honda TRX 400EX (TRX-400-EX).