[Kazoo2U]

Friendly reminder here:

If DIY rear diff, be sure to loosen the TOP fill plug before you loosen the BOTTOM drain plug. Old fluid is eminently more preferable to having no fluid at all.

 

[Kazoo2U]

The fluid will not drain from the top plug. Duh. 🙃

What are you going to do if, after draining out all the old fluid via the bottom plug, you find out that the top plug won't budge & you can't fill your rear differential with fluid?

Again, crack open the top plug before removing the bottom plug. If you can't open the top plug, don't open the bottom plug. Old fluid sure beats not having any fluid at all.

If nothing else, having the top plug cracked open will help drain out the old fluid.

 

[Kazoo2U]

Again, the fluid will just sit there. It won't drain from the top plug. DUH.

You need to be able to put new fluid into the rear diff after the old fluid has drained out. If you can't open the top plug to fill the diff, why would you drain out the old fluid? Once the old fluid has drained out, you can replace the bottom plug & begin filling the diff through the top hole after removing the top plug.

Once you see fluid dripping out of the top hole, insert & turn the top plug to torque specs. If you can't put in new fluid, why would you drain out the old???

Some forum members in the past did drain out the old fluid before they realized that the top plug would not budge. What we don't need is a another series of "what do I do now" posts.

 

[Kazoo2U]

No just the first oil change/tire rotation so far was around 8500 miles.

As with any maintenance procedure, you are the sole determinant as to what & when you do something to your vehicle.

While 8,500 miles seems a bit on the short side for a diff fluid exchange, feel free to do so, as long as what you are doing meets Honda specifications [especially which diff fluid to use] & does not compromise your vehicle safety or operations.