ford zetec garbox problem!!

[Sporty]

recently bought R REG 16v escort mk7 there is a noise coming from either the inner cv joint or the diff carrier bearing on the passenger side ,,i have had 1 mechanic tell me that itis the cv joint (which i believe very rarely go?) and another mechanic tell me it is the( diff bearing?).
Now thereis no oil leaking or any signs of oil from the diff seal but the cv gaiter did not have any retaining strap/clip holding it on and there was alot of grease around the bottom of the gearbox now i don't know how long the car has been driven with the gaitor in this poor condition prior to me buying the vehicle as the seller did not tell me about this problem
when you grab the driveshaft near to the gaitor you can clearly move it (upand down)quite easily showing quite a bit of play, however the driverside driveshaft does not move when you lift the passenger one up and down.Is there any gearbox specialists or mechanics out there who can possibly shed some light on this problem i have,

 

[AdamW]

If the gaiter comes off a CV joint, this can cause them to prematurely wear as all the sh*te off the road gets into them. Happened to a mate of mine with an Alfa, he had bought it without knowing this and it actually failed when he was driving.

When the mechanic had it up on the ramp, he noticed that the gaiter on the broken CV joint was not the correct part. For some reason the gaiter itself had been replaced earlier, with an incorrect one.

 

[Sporty]

well previously told it was the gearbox but have now been told it's probably not that as there is no noise coming from it ? looks like it could be the lower "wishbone arm" bush, and have been told to replace the arm! let'shope that's all it is and not the expense of gearboxes e.t.c. will let you all know if it was when i have a new one put on later this week!!