belt or a chain?

Both engines use chain.

 

how did u find they use chain? man then I'm set for not changing it ever!!
my last car was atima and it was chain! 160k!

 

All I had to do on my four banger was look down the oil cap hole and you can see it. Plus, you can tell by looking at the front cover. Belt drive engines don't have elaborate cast aluminum covers with seals and gaskets since there is no oil on the cam drive.

As for the 4.0, a brief web search confirmed my suspicions. Believe it or not, the majority of new engines use chain drive today. There are a few stragglers, but they are all coming along...

 

My opinion on this is that chains never have to be replaced because teeth are holding it in the same place...therefore it can never slip, nor stretch which should mean they never need replacement

on the other side of it.......belts are somewhat safer for your engine in my opinion because if they ever slip or break, no real harm done.......except maybe for your pocket.

but if a chain breaks....well there's a pretty good chance you will need a new engine at that point. cuz the chain can F up so many parts within



my opinion.......let toyota continue with chains because i have nothing but confoidence in them

as far as everyone else (the competition).....stick with the belt.... your vehicles already ahve enough problems

 

Chains don't need replacing because of how they wear. Unlike a belt, they don't have a finite life that ends in breakage. It is true that a chain won't slip, but it will 'stretch'. I hesitate to use that word because they don't really stretch...they elongate as the pins and aperatures (holes the pins ride in) wear. Over time, the extra slack is taken up by the tensioner (hydraulic via engine oil supply).

Belts are in most regards less safe for your engine compared to a belt. Most modern engines are interference engines meaning that the pistons will contact the valves if cam timing is incorrect. If the belt breaks (run one long enough, they will), you will need to replace valves and pistons. Not all engines are interference, but most new ones are with the amount of performance OEMs are trying to wring from them.

The good news is that Toyota uses Tsubaki roller chains on all their engines and they are pretty damn robust.