How to Change the Rear Diff Oil on a Honda Rancher

Like every other fluid in your machine, the oil that keeps the rear differential in your Honda Rancher TRX 350 cool needs to be changed every now and then. 

Grab the tools and parts needed and follow the steps provided to change the rear differential oil on your Honda Rancher TRX 350 in minutes! 

Tools and Parts Needed - Honda Rancher Rear Diff Oil Change 


  • 10mm socket
  • 12mm socket
  • Ratchet
  • 17mm box-end wrench

Honda TRX 350 Rear Differential Oil Change

Step 1. There's a plate underneath the machine that protects the rear differential. Remove the three 10mm bolts to get the plate off. If there’s a lot of mud caked between the differential and the plate, it may take some extra effort to remove it even after you get the bolts out. 

Step 2. Clean the differential with a brush if it's dirty to make it easier to get to the drain bolt and check bolt. 

Step 3. Get a drain pan under the differential, and remove the oil check bolt and drain bolt to drain off old fluid. Sitting at the rear of the machine looking at the differential, the check bolt will be on the left side. Remove it with a 10mm socket. The drain bolt is on the right. Remove it with a 12mm socket. Both of these bolts have crush washers, so don't lose them.

Step 4. Use your 17mm box-end wrench to remove the fill bolt. It’s located on the right-hand side of the differential up near the top. 

Step 5. Replace the drain bolt, making sure that you have the crush washer on the bolt. Leave the check bolt and fill bolt out. 

Step 6. Pour new rear differential oil into the fill opening until you see overflow come from the opening for the check bolt. 

Step 7. Once the overflow stops, replace the check bolt, making sure you have the crush washer behind it. 

Step 8. Replace the fill bolt on the top of the differential. 

Step 9. Use some contact cleaner to clean excess fluid off the differential and make it easier to spot any future leaks. 

Step 10. Replace the protective plate over the differential and tighten it in place with the three 10mm bolts you removed back in Step 1. 

You've just changed the rear differential oil on your Honda TRX 350, but have you changed the motor oil yet? It's recommended you change both at the same time, so why not get it done? Watch the video below to change the oil on your Honda Rancher ATV.



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