I'm pretty sure it's a chain. The 2007-on Tribute has a 2.3L MRZ engine which it shares with the mazda3 mazda5 and mazda6. And I know for a fact that the mazda5 has a chain.
The '01 Mazda MPV with the 2.5 Liter engine actually has two timing chains, one for each side of the V6 engine. This engine has 2 overhead cams on each side of the engine (DOHC) controlled by the 2...
Timning Belt that should be changed every 60,000 miles. (may as well also change the water pump at the same time).
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