https://www.valkyrieforum.com/bbs/index.php/topic,116696.40.htmlSo my conclusion is to make sure the U-Joint splines are correctly lubricated, to prevent the drive shaft to final drive splines aka spline coupling (SC) from wearing out. I also installed a new driveshaft to spline cup seal every other tire change.
The SC in a perfect application would have zero forward/rearward movement and would be submerged in oil which would result in zero wear and fretting. Fretting is a type of corrosion which gives that rust powder look. Is not from water intrusion. In some applications they actually glue the splines together to stop movement.
Honda provided the locking spring clip on the SC end of the drive shaft to help reduce movement of the SC, but it is still not a solid zero movement connection. So this is where the lubricated U-joint splines come into effect, thereby doing all of the movement, to reduce or actually eliminate any SC movement.
In a few of the links I provide it is stated that the SC splines should be hardened to greatly reduce wear. Did Honda do this to the parts?
In my case I inadvertently mixed greases with different bases for the u-joint splines, by re-greasing and not cleaning off the old grease.
My fault, at the time, I didn't realize they had different bases. So what happened the greases started to dry out and not provide the easy sliding movement as needed and the SC failed in 17k miles.
For re-installing the U-Joint boot I coated the inside lips with silicone grease and it pops on with zero problems. suggest not to use a silicone spray which has petroleum products in it and other things which could degrade the boot material.
So to bring this all together, proper lubrication of the u-joint splines is extremely important and should be done every tire change to protect the SC.
This time I used moly bearing chassis grease for the U-Joint for even more friction reduction and easier sliding.
For the SC I mixed TS-70 moly paste with some high temp grease so there would be about a 50/50 moly to grease ratio as recommended by the Dan Foss pdf which is a much higher percent of moly than the 3% moly grease the Honda manual calls for.
The following documents have some very good info about SCs and lubrication requirements.
https://www.machinerylubrication.com/Read/693/fretting-wearhttps://www.powertransmission.com/issues/0214/spline-couplings.pdfhttps://assets.danfoss.com/documents/76142/AI152986482538en-000304.pdfhttps://www.eng-tips.com/viewthread.cfm?qid=423609https://gearsolutions.com/departments/tooth-tips-a-brief-overview-of-splines/https://www.eng-tips.com/viewthread.cfm?qid=383504
