Mine just failed MOT on lower ball joint. Tested jacked the truck up and then observed the joint as he lowered the weight back down - it was really easy to see that there was some play in it.
I decided to tackle the replacement myself (did upper and lower whilst it was all off) and it was the job from hell! I had a ball joint press tool and it made not a blind bit of difference, they were in there for good and had no intention of coming out. 2 days of grinding, drilling, and beating them with a hammer I finally got them both out. In the end I used a slitter disk to take as much of the protruding housing off as possible then beat them with a hammer and a socket to knock them out.
Putting them back in was just as much of a pain in all honesty. Top one went it relatively easy without too much of a fight but the bottom one was a nightmare. In all it took me about 3 hours to get it fitted and then a day to recover from hitting my hands constantly with the hammer.
All in all it took me about 3 days from start to finish - but it was definitely 3 days of fighting! Checked once the job was done and there was no movement in the ball joints at all - as it should be. Any 'play' in a ball joint should be a MOT failure unfortunately.
My advice is a) buy the ball joints and get them done (they are about £10 each of internet) and b) get a quote for someone to do it at a garage and decide if it is worth spending the money or not. I didn't get a quote from a garage but quite frankly it is one of the few jobs I have done on the Disco that I wish I had made someone else's problem.
