How to Change the Oil in a Honda TRX 400 ATV 

Regular oil changes for your Honda ATV can slow the toll that heat and pressure take on its engine. Doing your own oil changes is a quick and inexpensive process that even beginner mechanics can pull off.

Watch the video above and follow the steps below to change the oil and oil filter in a Honda TRX 400.

See the parts diagram: Honda TRX400 right crankcase cover diagram

Tools and Parts - Honda TRX 400 Oil Change

Buy Honda HP4 synthetic oil

Buy Honda ATV oil filter

NOTE: A Honda ATV works on a dry sump system, meaning it has oil in both the crankcase and the oil tank. You'll need to drain both.

2007 Honda TRX400 ATV engine oil change service

Honda TRX 400 ATV Oil Change Steps

Step 1. Run the engine for a couple of minutes to get the oil circulated through the system. Stop the engine, then loosen the dipstick (located on the left side of the motor) and place a drain pan underneath the motor. 

2007 Honda TRX400 ATV engine oil change

2007 Honda TRX400 ATV oil change service

Step 2. Use a 12mm socket to remove the drain bolt for the crankcase (located low around the circular crankcase cover) and the crush washer behind the drain bolt, making sure not to lose the washer as the oil comes out. 

2007 Honda TRX400 ATV oil change

Honda TRX400 ATV engine oil change service

Step 3. Place the drain pan underneath the oil tank, and use a 14mm socket to remove the oil tank drain bolt (located in front of the engine), again making sure not to lose the crush washer behind it when you pull the bolt out.

Honda TRX400 ATV engine oil change

NOTE: While the crankcase and oil tank drain, move over to the right side of the engine to change the ATV’s oil filter.

Step 4. Use an 8mm socket to loosen the two bolts holding the oil filter cover in place.

Honda TRX400 ATV oil change service

NOTE: The oil filter cover is a small cylinder next to the larger circular crankcase. Place something underneath the cover to catch oil that spills from removing it. 

Step 5. Remove the oil filter, making sure to keep the spring behind it hanging on the case inside the filter chamber. 

Honda TRX400 engine oil change service

NOTE: Don’t lose the spring, since it needs to stay in place behind the new filter.

Honda TRX400 engine oil change

Step 6. Install the new oil filter

Honda TRX400 oil change service

Honda TRX400 oil change

NOTE: Make sure the spring is still hanging at the back of the chamber before you install the new filter. Putting the filter in backward causes serious engine damage.

Step 7. Reinstall the filter cover and its two bolts, then tighten the bolts snug.

Honda ATV engine oil change service

Step 8. Tighten the 14mm drain bolt with the crush washer on the oil tank, then do the same with the 12mm bolt on the crankcase. Thread both by hand first, then tighten them to 12 or 13 foot-pounds of torque. 

Honda ATV engine oil change

Honda ATV oil change service

Step 9. Fill the engine with 1 quart of Honda 10W40 motor oil. Next, screw the dipstick in place and run the motor for 10-15 seconds to circulate the oil, then stop the engine and check the oil level on the dipstick. 

Honda ATV oil change service HP4 synthetic

NOTE: The Honda TRX 400 uses 1.9 quarts of oil. Before filling it up, check the capacity of the engine, and keep in mind that all of the oil will probably not go in at once. Some oil has to move up into the crankcase to make room for more in the oil tank.

Honda ATV oil change

How to change Honda TRX400 ATV engine oil

How to change Honda TRX400 engine oil

Step 10. Add another ¾ of a quart and replace the dipstick, then run the engine again for about two minutes. Finally, top off the oil to bring the level on the dipstick to about three-quarters capacity.

How to change Honda TRX400 oil

How to change Honda ATV oil

How to replace Honda ATV oil

 
OIL FILTER
Honda

OIL FILTER

Qty.
Oil Filter
Aftermarket

Oil Filter

Qty.

body

Why Partzilla?

Commercial Discounts

Special discounts for companies in the powersports industry

Details

Government Sales

Discounts for federal and most state and municipal agencies

Details