When I had to have new driveshafts installed on my XR's they were smaller in diameter compared to the earlier version of XR driveshafts and they came with non-greesable u-joints (no zerts). The earlier u-joints had a zerts greese fitting on them and now the newer version does not. Don't really know if the non-greesable u-joint is good or bad, but it looks to be Merc's latest design.

yup ....means mo bucks for merc ....

Bravo 1 ujoints are still available, XR/XZ are not, then you replace the whole shaft as Kaama said.
The ujoints are not that hard to change, by the time you finish with the last joint you will have it down pat, well if they are all back together the way they came apart.. I guess I need to charge more??

Bellows is another matter, not for the faint of heart. Not part of the drive, so I dont do that. Still think I need to charge more..

Hope this helps
Dick

What would cause a bellows to go bad (leak) at 55 hours?

Cruising with drive trimmed and bellows exposed, hit a small piece of debris, it kicks up and pokes a hole in the rubber bellows.

Or sabatoge.....I had someone cut my bellows while the boat was on the rack. replaced 3 in a month.

I had both go bad the same week (Last week) within two days of replacing the first one. Less than 60 hours on them. All U-Joints gimbels seals had to be replaced. Apparently they had been leaking since the last lower unit oil change (Or sooner) that I had done end of last year at 50 hours. Thought it was strange.

critters

muskrats will sometimes chew on the bellows. i've heard a few tales of people leaving their drives trimmed up at the dock, and coming back to find their boat on the bottom because a muskrat chewed through the bellows.

They better get a bigger bilge pump then
Unless someone could tell me difference I would think it would be a tale.
The water would only drip through the gimble bearing and I was told that was part of the design.
The exhaust bellows would not allow water into the boat.
I have heard of the old OMC where the big rubber boot sprang a leak. That would fill up a boat fast.

Smart choice. This work does not require a PhD, but you can get into trouble if not familiar with the process. Doing it it all at once is more cost effective, long term, than one piece at a time. The only thing worse than being the one dicking around on a nice day is being the one dicking around fixing what you just finished dicking around with, on another nice day.

The Muskrat deal was fairly common with the older OMC stern drives, I have seen a couple go down after a good chewin by the little critters. The Merc design would take longer for sure, and only thru the driveshaft boot.

So those U-Joints are Merc only sizing and not a standard U-joint that can be bought from a bearings supply house? Seems odd. Sucks haveing to spend $400 to get a $10 part.