It's a visual inspection for the fronts..hit it with a wire brush then some cleaner check for worn bearing cap bores or cracks, also the yokes for damage/distortion..when mine went it made a knock type noise at low speed and I think I had some issue w/4x4 not sure exactly what it was, been some time now..If the prev owner didn't then it's got to be time..lemme know how it goes

 

Okay, got under the truck today to check things out and found out what was causing my vibration at 30 mph. The transfer case was coming loose. Now to get the drive shaft back in.