Nissan Patrol 4x4 (Africa)

Can anyone tell me what the normal life expectancy of standard shocks and after market 4x4 shocks are.
I installed OMEs in early 2011, about 60,000 km ago.
Mileage included a variation of trails, and long distances when loaded.
How long can it still go before I will need to consider replacement?

I bought my Patrol with TJM's already fitted in 2009 and now 90k km's later I can feel they are getting a bit soft but there are no leaks - just a bit more body roll than in the past. I would say if you don't do anything stupid they should easily last 100k km's

I had to replace my OMEs after 80000km, but very few offroad usage.
I replaced with TRAILMASTER, damaged after 20000km (what a scrap)
Now I have Ironman, but only since 7000km.

For what it's worth :

I replaced my first set of shocks with OEM at +- 250 000, then at 610 000 I replaced all coils shocks etc with aftermarket (EFS)

I do a lot of bad potholed roads in Limpopo and a fair amount of gravel roads, now and then serious off road.

Now on 730 000 km and all still fine...