It appears from my quick inspection that the transmission main shaft oil seal (behind the drive pulley) has started to weep (about a drop per week when the bike sits). This weeping just started about two or three weeks ago, and only about a drop per week, so not much. But that is not my primary concern. The seal (if that is the problem) could fail completely at any time (and that would be a serious problem). So then, does anyone have a cost estimate of how much dealers charge to replace this seal? Seems to me that the largest cost is just in labor to get at the seal (remove/replace primary, etc.)? Thanks.

 

Why not just call the dealer and ask?

 

No more than it is leaking, I would keep on riding.

 

I would put some 85w140 DINO gear oil (like valvoline or Rotella)in the trans to buy you some riding time to shop dealers and indy shops for the repair if you don't want to DIY. Don't put synthetic in or it will leak more. The seal most likely wont "blow out" all at once unless you are Evel Knievel with it. The leak will just get progressively worse. That said. you don't want to score the shaft with a bad seal so it needs to be repaired.

 

Had mine done at an indy and it was under 300.00.

Still leaking though, that's why I now have a new main drive gear sitting in the tool room as well.......................

 

The mainshaft cannot be damaged by a bad seal, it does not contact the seal, the spacer contacts the seal. Fix it this winter...

 

Unable to find Shell Rotella gear oil here in Idaho Falls (don't know why, tried every place I thought would have it), I then did what every, red-blooded Harley rider does when they need something. I checked Amazon.com, and there it was. Free shipping (when I get some new CD's). $3.99 per quart. I wonder what Amazon.com has in H-D parts? Better go check ......

 

I have a friend that has had this issue...and still does after we replaced the seal. The dealer wanted $350-or-so, but we replaced it on our own. You just have to pull everything off the left side of the bike to get to it. Anyway, like one post above...it still leaks a little. The dealer told him not to put so much fluid in there. Yea...sure...the way to stop any leak is just not put the fluid in. The next time we do this I have an idea of what I plan to do. Seals can be obtained in just about any configuration and the numbers on the seal relate to diameter, thickness and center-hole diameter. I think we will try one with a smaller inside (shaft hole) diameter. Not much mind you, but maybe a mm or so smaller for a better fit. A new sleeve should do the same, but it seems to me a little smaller seal would also and you won't have to pull that sleeve.

 

Replacement of this seal might well be my winter, sit-on-the-garage-floor project. Looks like an easy fix, and a slightly smaller seal might do the trick. I will ask at the local dealer what they would charge.

 

I had a similar problem with a shaft on a tractor....no it was not a Harley tractor, but the same principle applies. After two seals over the course of two summers, I tried it again, but this time my parts guy gave me the wrong seal. I realized this when I compared the numbers just to make sure I had the right one. The one he gave me was 2mm smaller in the center (shaft) opening. I almost took it back, but said...what the heck and installed it. I greased the shaft and the inside of the seal real good and slipped it in. That was two years ago and I have since sold the tractor to a friend. As far as I know....that seal still does not leak. It was on a shaft very similar in size to a transmission main shaft.