Well I’m not sure that’s the correct title but I really need some help/advice

my girlfriend just bought a 2000 (year) freelander

when we bought it, it had already had the prop shaft taken off it.

she wanted it 4wd and the guy in the garage said he could put one on.

id read a load of internet stories about why people take the prop shaft off. So asked the garage are you sure it was as easy as adding the prop shaft back on. He said yes and there wouldn’t be any problems.

anyway she picked it up when I was away. Started driving to her mums and started to hear a noise. Rang the garage they said to drive it back… it didn’t make it lots of noise and smoke.

apparently it’s the rear diff… oil over the exhaust caused the smoke.

im still away and I’m just writing on here to understand what could of happened.

the garage said they could put a new diff on for no labour charge.. is it as simple as that or could it be something they did that could have caused the diff problem?

any advice or insight would be great.

im in Portugal.