Hi , sorry if this sounds a daft question I have a 2001 ford maverick xlt 3.0 24v automatic I believe it has a duratec engine I think it has a timing chain as opposed to a belt , I have been told by a few people that the chain is maintenance free and will not need replacing , if it does have to be replaced can anyone tell me after how miles should I be looking at to have it renewed , thanks for any help on this ,cheers .

It is a bored out ST24 engine pretty much, and due to the V configuration it actually has 2 chains. They should be maintenance-free, as long as the vehicle has regular services it should last the life of the car. I had an ST24 which was the 2.5 version, and that managed 205k on the original chains, and it hadn't been looked after and driven hard for years. If it starts to become noisy (and you will be able to tell it is the chains by the noise) then get them looked at/changed, but they should be okay.
You may get contradicting advice here, this is going from my experience.

Hi , brilliant thanks for taking the time to reply appreciate the help cheers .

As Goodkat says, they should last the life of the engine as long as it has been looked after with regular oil & filter changes.

The odd time ive changed the hydraulic chain tensioner that was faulty.

Cheers Ade, as you can see I am no expert mechanic, I have done bits and pieces on my cars through the years ,when you say about changing the chain tensioner I am assuming that when you do that the car is in bits would it be worth putting new chains on at the same time or just replacing the tensioner leaving the old chains in place ?

As long as you can see the chain isn't worn and inside the engine is clean and not full of black sludge then if you have a noisy chain its usually down to a weak tensioner.

Thanks for that hopefully when I retire I will get more chance to tinker around with my motor so getting as much info as I can before I let loose with my spanners again , Cheers Ken.