Have a denali, when i change oil, oil gets inside the u-joints for the 4 wheel drive..will it hard the u-joint?

I place a shop towel over the u-joints on the chevy and gmc 4 wheel drives but it will not hurt it it is just messy and people will come back thinking there oil is leaking.|||Shouldn%26#039;t|||No , It will help to reduce wear on the U-joint.|||the u joints are a sealed section really, and given that i have seen thousands over the years, i have never seen one that was that close to the u-joints, even the 8 liter engine does not have a straight shot. it will hit the exhaust but not the drive shaft.