GL1500 water in final drive

There is a vent at the top of the final drive.... Could be damaged or missing.

How old is that oil ? , i would change it now , and Again after a good long ride , and then check it Again in a year or so .

It could be just moisture. Change the oil and forget about it.

As you didn't change it yourself you can't be sure what the PO used. He might of used an old open bottle that had been in a damp shed for years! Change it and forget it.

One can never really know previous Wing maintenance or lack-of. The PO on mine had evidently neglected r/e lube change for 18,000 miles since new. Oil was FILTHY!
I used Valvoline full synthetic r/e lube. Only became clear after 4 dump/refill cycles in 2 days, w/short ride between each. TTFN.....Old Tom

I certainly wouldn't 'change it and forget it'. If you are riding in wet or moist conditions then the vent is the most likely cause. The vent is available from Honda and easy to install. Just have to NOT push it on too far.

If your bike is a daily rider then check the oil through the filler hole after about 1000 miles. Then again after about 5000 miles if the first check looked ok.

final drive

with water being in your final drive, you could have washed the bearings and gears and new oil wont want to stick to them. I believe you should flush it with a good type of flush first. put the bike on the center stand and run it in gear for a few minuets( don't rev it up ) then drain and fill with oil.( be sure back wheel doesn't touch ground ) have someone sit on front fender.

Thanks all. I just got back from a 2000 mile trip and had no problems. The vent appeared to be intact so just flushed and refilled (didn't have time to get a new vent before I left). Drove through a day of rain and didn't see water in the oil after I arrived so who knows. I did order a new vent and will install just to be safe

Just know that water in high sulfur oil (reduces sliding friction of hyphoids) results in sulfuric acid (H2SO4). This will etch the faces of the gears, if left on too long. Sounds like you caught it in time. Maybe take is easy for a while to burnish the faces back in, and change it a couple more times.

http://www.stle.org/UserFiles/File/certification/Combatting Wear pt9.pdf

Boundary Layer (BL) lubrication

DO NOT sit on the front fender of a 1500 unless you like to purchase plastic . This fender is known to break under the weight of farkles mounted to them . I think there were at least 2 members here who had front fender issues last yr .