The Elusive 3rd O-ring

Every time the rear tire is changed, it is time to replace the three O-rings which keep the moly paste in place. Two of the O-rings are immediately found, but one is not so obvious.
Part number 91358-MG9-003 (50.5mm x 3.5mm) goes in a groove adjacent to the splines on the final driven flange. First O-ring
Part number 91304-KT8-003 (61mm x 2mm) goes on the shoulder of the wheel. An alternate number is 91302-MA6-003. You will see this one when you pull the final driven flange off the wheel. Second O-ring
Part number 91356-MG9-003 (39.5mm x 2.4mm) is the elusive third one. It is found in the final drive, where the final driven flange splines mate up to the ring gear splines. In the picture, a small screwdriver is shown stretching the O-ring a bit out of its groove. Third O-ring
In case you need a reason to religiously replace the O-rings and lube the parts with Moly paste, here's what happened to Mike Sumner's splines. Contrast them with those in the first picture. $$$$$$$! Third O-ring

Now that you know where the O-rings go, here's the scoop on where the moly paste goes, per John O., "The Honda manual's a little confusing. Simply, the lube icon on the first Rear Wheel Removal/Installation schematic should be an "MP", not an "M". The 'Note' on the second page doesn't mention the percentage of moly, BTW. The remarks section on the 4th page specifically calls for moly *paste* all over the Final Driven Flange. Also, take a look at the Lube-n-Seal Pts section of chapter 1 in the Honda Service Manual for more info/confirmation.

"Only use moly *paste* with a Molybdenum Disulfide content of 40% or greater on all the rear wheel R&R parts... drive splines, thrust washer, etc. No puny 3% 'grease' STuff in this area.

"Recommend: Pro Honda Moly 60 Paste, PN: 08734-0001 / PASTE (MOLY 60) or this Loctite alternative, PN:51048 - Moly Paste [65%]"

Here's an illustration showing how much moly paste to use and where to use it. More approved materials are listed, too.


After following the above procedure for a number of years, I found that the portion of the wheel where the final driven flange mates, shown in the second photo above, showed a considerable amount of wear. Someone told me that moly paste is not appropriate for use on aluminum, except as an anti-seize lubricant. In this application, there is small but continuous movement, so it doesn't qualify as an application for an anti-seize lubricant. I have accepted this as fact, and have started using grease in this particular location instead of the moly paste. YMMV

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Last updated on January 26, 2014     © 2014 M. E. Martin, all rights reserved.