Auto Parts: timing belt, chain tensioners, independent mechanic

Question
Hi,
   I have a 2002 Ford Explorer with the 4.0 engine.  It has 80,000 miles on it.  I just spent $2000 on bearings, rotors etc from the effects of salt on roads.
   Now I took it in to Ford for oil change and they said my timing chain guides sound bad and they need to change it all and that it will be very expensive.  Can you tell me what is involved and how much money I will need to spend and what will happen if I let it go?  I do hear a sound from the engine now.  Is the Explorer just a bad car?

Answer
    There are hundreds of thousands of these engines on the road.  They are very reliable.  I think you are suffering from "dealers need cash" syndrome.  It is possible that the chain tensioners need replacing, but it is highly unlikely.  If it was me, I'd keep driving it until the noise became obvious.  My guess is that the dealer pointed out a noise that's been there all along and now you can hear it all the time.  I'm sure the dealer will charge a lot to change out these parts.  The parts themselves are relatively cheap.  When it really does need it go to an independent mechanic.