i have a w250 and i put a 4 in lift and when i put it in 4x4 it makes a loud humming noise. im thinkin with a new angle from the lift that the u-joints are bad and is rubbin somewhere?? and when its out of 4x4 but the hubs are still in the noise is still there. any ideas?? its 81 3/4 gas 360

 

the lift that you put on might of taken out the u-jionts it has happened to may people before. you might have to go to a cv-jiont. or your u-jionts might of been bad from the start.