hi i have a 2004 disco td5 manual with 120k showing on the clock, whilst touring spain last year we noticed a vibration at 70mph that turned into a managable drone at 90mph+ but you cant drive everywhere at that speed as its hard on the wallet. As i do a lot of towing and rarely drive above 70mph its not really worried me but whilst looking under it today i checked props for play and found a small amount of play from the front of the transfer box where the front prop joins so i suspect its the front output bearing can this be changed whilst the gearbox is in situ and if so any idea on the time this should take a competent mechanic thanks for reading