This question is just to give me an idea so I can be prepared for it. I live very Far far away, so I will probably order a couple spares. I Jeep off-road as often as possible weather it be during the week, evening or week-end. and it's rough off-road, through deep mud, tundra, climbing over mountains etc.
All that said how long can heavy duty joints last From drive shaft to the steering?

Wear on the steering column joints is pretty dependent on how often or well you lube them. I've seen them wear out in under 100,000 miles on jeeps were they were never lubed. There aren't any fittings on the stock shaft, so you're reduced to spraying white grease on them and hoping.

If you want to be sure, just buy an entire replacement, wrap it in paper and put it aside until you need it. Another approach is to buy one of the aftermarket columns that has roller bearing joints. Thats an expensive approach.

My front u-joint on my D-30 lasted about three years - the new ones with the
lube points never died. I always take my drive shafts out in my prep session
before jeep season here in AZ and have them balanced and checked.

I have a CV drive shaft in the rear - it does need maintenance and gets greased
every time I'm under the jeep - 1K - or less. No way I can do a u-joint on this
in the field - it too complicated - resigned to getting a spare and just leaving
it in the spares box.

My front u-joints on the passager side seemed to die - after I got my ARB lockers
in I started replacing them every two years just to make sure they did not on me
in the field. I think the volcanic ash we have here in AZ kills u-joints.

I'm pretty sure the first front u-joint failure I had was because I used my winch
to pull a five ton truck out of the sand - I think I pinned the tire on a rock and
torqued it too much.


Also I do 30K of hard core offroading a year... That might be twice , or even three times
what the average jeeper does... It's AZ ...

I also put after market seals on the D-30 - you see them advertised - they have
two o-rings and replace the small plastic piece of crap the factory puts in.