I have 132K miles on my G500. It is getting a new cardan shaft today and redoing the engine mounts at the same time due to evidence of wear and cracking. Done at the MB dealership b/c they are great with warranty work and I was worried about the drive shaft longevity.
They replaced a front window regulator twice on my 2002 under warranty, no charge. Turns out dust and off road vibes make the last even shorter than trips to the mall.
1999 G500 463.241
1997 G300td 463.330
1986 300GD 460.333
1983 280GE 461.213