Instead, you should focus on listening for unusual noises from the engine. A rattling or slapping sound coming from the engine, particularly at startup, could indicate a problem with the timing chain. Other symptoms might include a rough idle or a noticeable decrease in engine performance.
If you hear any of these sounds or notice these symptoms, it's crucial to get your Tacoma inspected by a mechanic immediately. Ignoring a failing timing chain can lead to catastrophic engine damage, a far more expensive repair than a proactive chain replacement.
While there's no scheduled replacement, some mechanics recommend considering a preventative replacement around 200,000-250,000 miles or if the vehicle is significantly older (15+ years) *and* exhibits unusual engine sounds. This is purely preventative, however, and based on the general lifespan of chains in similar vehicles, not a guaranteed necessity. Ultimately, a mechanic's assessment is the best way to determine if your timing chain needs replacing.
