Instead of a predetermined mileage, consider these factors:
* Mileage: Higher mileage significantly increases the likelihood of needing a replacement. However, even lower-mileage vehicles can experience chain wear.
* Maintenance History: Regular maintenance, including oil changes with the correct oil weight and frequency, greatly extends the life of the timing chain. Neglecting maintenance drastically shortens its lifespan.
* Sounds: Listen for unusual noises from the engine, such as rattling or clicking, especially during startup. These could indicate chain wear or tensioner issues.
* Performance Issues: Poor engine performance, misfires, or rough running could be signs of a failing timing chain.
In short: You don't *automatically* need to replace the timing chain just because it's a 1995 Jeep Grand Cherokee. However, it's crucial to have a qualified mechanic inspect it during regular maintenance, especially if the vehicle has high mileage or shows any of the warning signs mentioned above. Prevention is key, and a failing timing chain can cause catastrophic engine damage if it breaks.