Anyone know why I have gear oil coming out of the vent tube on my rear differential. Drained it and put exactly 400ml back in as per my owners manual but still leaking out of tube.

[2015 Z Force 800 53/Trail EPS]

Most often it is because it was or is overfilled..was being that there is still some up in the tube that gets pushed-out as the air in the diff heats and expands. Pull the tube, hit it with some compressed air to clear it...but it will make a mess on the end so maybe catch it in a rag.

Odd, I had this issue yesterday after 500 miles which made a mess. If mine was overfilled, should have happened by now?

[2015 Z Force 800 53/Trail EPS]

Odd, I had this issue yesterday after 500 miles which made a mess. If mine was overfilled, should have happened by now?

I ran mine overfilled sense the start and had no problem until I ran a few runs down open roads at 30+ MPH for miles. Even then it was just enough to kick some out and drop on the muffler heat shield and smell. Next oil change I will put in only what the book says but until then my little catch-can mod is taking care of it. Think it's in the How-Tos.
Large discharged indicates either overheating... or additional expansion from water in the oil.

Drained and installed 400 ml Mobile synthetic 75w-90 in the rear axle, so far so good.

Spoke too soon, did it again last night.

[2015 Z Force 800 53/Trail EPS]

Spoke too soon, did it again last night.

Might be time for the catchcan mod. Mine hasn't done it after I did it and I still over-fill it.

https://cfmoto-forum.com/how-to's/oillube-catchcan-mod-for-ifferencials-and-gear-cases/

Spoke too soon, did it again last night.

Might be time for the catchcan mod. Mine hasn't done it after I did it and I still over-fill it.

https://cfmoto-forum.com/how-to's/oillube-catchcan-mod-for-ifferencials-and-gear-cases/

It would have to be much larger than that observing the amount that pukes out.

[2015 Z Force 800 53/Trail EPS]

Spoke too soon, did it again last night.

Might be time for the catchcan mod. Mine hasn't done it after I did it and I still over-fill it.

https://cfmoto-forum.com/how-to's/oillube-catchcan-mod-for-ifferencials-and-gear-cases/

It would have to be much larger than that observing the amount that pukes out.

You have something else going on then. Are you sure there is no water or moisture in it? How hot is it running?

Spoke too soon, did it again last night.

Might be time for the catchcan mod. Mine hasn't done it after I did it and I still over-fill it.

https://cfmoto-forum.com/how-to's/oillube-catchcan-mod-for-ifferencials-and-gear-cases/

It would have to be much larger than that observing the amount that pukes out.

You have something else going on then. Are you sure there is no water or moisture in it? How hot is it running?

I just completely drained it. I can check with a heat gun.

[2015 Z Force 800 53/Trail EPS]

So no water ...one thing checked-off. Any odd noises especially during deceleration?

So no water ...one thing checked-off. Any odd noises especially during deceleration?

No, 600 miles on machine.