Last year after riding my 97 Ultra Touring about 125 miles, I noticed it leaking oil on the garage floor. Looked like chaincase oil, so I checked the level, and it was down a lot. Figured I'd replace the oil seal before riding this year. Well, after looking it over last weekend, I can't feel any oil on the bottom of the chaincase, and it hasn't leaked a drop in the last almost 6 mos. There's nothing in the pan (nothing fresh, anyway), and I can't see any obvious signs of where it was leaking. Has anyone seen this before? I'm more than willing to replace the seal, but if that isn't the problem, then I'd hate to get into the riding season and have a major repair to do. I appreciate any thoughts!

Confused by your note a little. When you say oil seal are you speaking of the seal between the chaincase halves, or the seal running on the mag side of the driveshaft?

Do you see a mess on the inside of the tunnel around the driveshaft seal?

Thanks for your reply. I was originally thinking the seal between the chaincase halves, but I did notice some oil/dirt on the inside of the case (on the mag side). Nothing wet, but a greasy dirt. I keep my sleds clean, so the crud is not likely from an oil spill (while filling the tank) or something like that. Think that's my problem? It might explain why I loose oil while running, but not just sitting.

If you have oil below the level of the drive shaft then it is probably the seal on your drive shaft. If the oil is gone either the chancase seal is bad or maybe the plug fell out. I would replace the seal and bearing as if it did run dry (or way low) it would not do your bearing any good.

For the most part, the bearings are factory sealed with grease inside, your more apt to have a chain and gear malfunction if your oil gets low.
In your year sled, there are chaincase seals on the backside of the chaincase, along with seal sleeves and a seal sleeve o'ring on both the axle and jackshafts, chances are one or both seals have gone bad, and or a bearing may have went which could have caused a slight misalignment of a shaft, which would then wear crooked on the seal causing it to fail, I haven't seen it real often in my shop, but I have seen it.

Don / Performance Parts

I assume I would have to remove the whole case to replace the seals on the back. Is this a huge job? Replace both while it's out? thanks!

Yes you would. Not that bad, I would replace both seals and bearings too. Check out the seal sleeves also for any possible grooving, (unlikely).

case shouldn't need to be removed. seal goes in from tunnel side and bearing into case from inside case.

Had problem with my 97 Ultra SP. Replace the Chaincase gasket i.e. seal on the cover. Costs $6-$7, if you try to reuse it will work for a while (like mine did) but it has a special lip that gets bent and won't seal properly so best to put a new one on. You will see when you put your old one next to the new one. Don't forget to put gasket seal on the top where the two seal ends met together, just a small drop is needed. The gasket is not a circle but a line that joins on the top). Check you drain plug also and perhaps put some silcone on it.

Racer Dave,
If the seal goes in from the tunnel side, does that mean I have to pull the jackshaft and/or the driveshaft?

Rear skid and driveshaft. If you have the 4 driver drive shaft you May have to pull the chaincase. I've never done one of those. I've only pulled 2 and 3 driver shafts. They come out without case pulling.

You are right Dave, if a two or three driver axle, you could do it without removal, I assumed he had 4 Which does require removal. I would say that, it is a bit hard to get the seals at proper depth and straight though, with it on, not impossible however. We usually just take off the chaincase and inspect everything for wear and possible cracks.

RacerDave and xcr1250, thanks for your help. My memory tells me it is a 4 drive. I'll check over the weekend and confirm. If the seals can be replaced by pulling the chaincase, isn't that easier than dropping the skid and pulling the driveshaft? Or does that need to be done anyway? My book (factory manual) is very poor in this area, so to say I'm confused would be an understatement!

You'll never be able to replace the chaincase without removing the skid, you would destroy the seals.

Ok guys, thanks for the info.