How to Change the Oil on a Honda TRX300

Clean oil keeps an engine running smoothly, and is an essential ingredient for basic ATV maintenance. 

When you're ready to change the oil on your Honda TRX300, follow the step-by-step guide below and watch the video above for reference while you work on this job.

Tools and Parts Needed - Honda TRX300 Oil Change


  • 3/8th ratchet
  • 17mm socket
  • 8mm socket
  • Torque wrench

Changing the Oil on a Honda TRX300

Step 1. Crank up the engine and run it for a couple of minutes to warm up the oil. 

PRO TIP: The heat will thin the oil, making it easier to drain.  

Step 2. Turn the engine off and remove the dipstick. 

Honda TRX300 oil change service

Step 3. Locate the drain bolt underneath the unit to drain the engine. Get a drain pan underneath and remove the bolt using a 17mm socket.

NOTE: Be extra careful not to lose the crush washer on the drain bolt.  

Honda TRX 300 oil change drain bolt

Step 4. Once the engine drains, reinstall the drain bolt with the crush washer, and use a torque wrench to tighten it to 18 foot-pounds.

Step 5. Remove the oil filter cover by taking off the three 8mm bolts holding it in place. 

Honda TRX 300 oil filter cover

Step 6. Remove the oil filter.  

Honda TRX oil filter change

Step 7. Clean the inside of the oil filter compartment with a rag. 

NOTE: Be careful not to lose the spring at the back, which needs to stay in place.  

Honda ATV oil filter change

Step 8. Install the new oil filter

NOTE: The oil filter is directional, and the black grommet should be facing you when you install it.

Honda TRX 300 oil filter change

Step 9. Replace the oil filter cover, and use your 8mm socket to tighten down the bolts.

PRO TIP: There is no specified torque here, but you don't want to overtighten them. 

Honda TRX ATV oil filter change

Step 10. Fill the engine with motor oil.

NOTE: Honda specifies that the TRX300 engine takes 2.4 quarts of GN4 10W40 oil

Honda TRX ATV oil change refill

Step 11. Replace the dipstick, then run the engine for a minute or two to circulate the oil and check the level. To do this, remove the dipstick, wipe off the oil, and then place the dipstick on the crankcase without screwing it down. Top off the oil if necessary. 

Honda TRX300 oil change level dipstick

The steps for changing the oil on a Honda ATV are the same or similar for all models. However, if you want to see this job performed on a different model, watch the Honda Rancher 350 oil change video below. 







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