Final drive gear oil should be 75W90 or 80W90
, synthetic is best (Redline, Amsoil or Mobil 1).
Q: Just changed the final gear case oil on my '04. Odometer:495 miles. Was a little shocked to see the color of the oil that came out. Rather dirty. Guess that's why they want it changed this soon. Replaced with Penzoil Marine 75w90 API GL-5 full synthetic. I am amazed at how easy self performing the maintenance is on this bike. Nothing seems too hard to get at and even an idiot like myself can do these things. One little thing I did and please scold me if I shouldn't have: When changing the final gear case oil, with the bike up on the center stand, manual says to fill it to the bottom thread. I filled a bit at a time, allowing the oil to settle at ten to fifteen second intervals. I also had the bike in neutral and rotated the back wheel each way during the process. Noticed when the wheel is rotated backwards, the gears grab the oil and propel it forward (toward front of bike. Forward rotation throws the oil back and up over the threads of fill hole). So once I got the oil up to the threads and it would drizzle out a bit with no wheel motion, I continued to turn the wheel backwards with my right hand, added a little extra squirt (not much) of oil with the bottle in my left hand, kept the wheel going, set the bottle down, grabbed the filler cap off my lap and put it on. I felt this would ensure a 'full' case. Bad move? It really was a negligible amount, a few mls at most. Rick in Texas
A: That's pretty much what I do... Fill to the top of the threads, give the wheel one spin backward, fill to top of threads, and close it up. I've done this every 6k mi (now have 26800mi on my 01) and I've never noticed any 'overfill' flying out of the hub.... jm
I used Castrol 80W 90. I do not think it really matters as long as it meets the GL5 spec. It says to use a 90 w above 45 degrees but all I could find was 80w 90. Mike '89 vn 750
Just changed mine out at 500 miles. Pennzoil Marine 75-90 100% Full Synthetic. Slicker than snake snot. El Cheapo at Wal-Mart.
See Final Drive Seal