Originally Posted by Rubber314Chicken
Why don't they make the serpentine belt a chain? For some reason I thought of this today, and it makes sense. Because chains are a lot less likely to break, right? I know Toyota has started using timing chains in some of their stuff, which means that you don't have to change the timing belt every 60,000 miles, so why not do the same for the serpentine?
They do, an old car my dad used to have had a timing chain rather than a timing belt.
(it was a ford Granada).
in general they are extremely reliable, but do require regular maintenance, like grease and oil, usually chains can stretch, but I'm not sure that these chains are under enough stress to actually stretch too much.
in any case, the service interval for adjusting the chain tensioner is going to be something like 60,000 miles, which is the same service interval for replacing the rubber belt, so you're not loosing anything!
the downside to using a chain is that it's a lot noisier than a rubber belt, (though personally having had a belt snap before, I'd likely prefer a noisy chain and a working engine than a rubber belt and an expensive rebuild!