AUII Timing Chain?!

[domnicosia]

Hi Guys,
I am new to the forum, and new to Fords. So please make allowances for my dumb question.

Having checked under the bonnet of my recenty aquired 2001 Falcon AUII Wagon I have figured the 6 Cylinder 4.0 Litre engine uses a timing chain rather than a belt.

I have never owned a car with a timing chain, so I was wondering does this part need to be repalced at any particular mileage like belts do. Do they ever fail.

Also thought I noticed that this engine has a lamda sensor just on the exhaust down pipe, is this correct?

Cheers

Dom