Once a Jeep wheel bearing starts making noise, it typically has anywhere from a few hundred to about a thousand miles left before it fails more seriously, though this varies a lot. The noise itself means wear has already begun, and it only gets worse and progresses faster the longer you keep driving on it.
There's no exact mileage that applies to every Jeep, since how quickly a noisy bearing deteriorates depends on how you drive, the roads you're on, and how much play has already developed inside it. Stop-and-go city driving around Ann Arbor puts different stresses on a bearing than steady highway miles on I-94 do, and rough roads or potholes accelerate wear more quickly than smooth pavement does. A bearing that's just starting to hum might last longer under gentle driving than one pushed hard on a bumpy commute.
What's more important than counting miles is watching how the symptoms change. If the humming gets noticeably louder week to week, if you start feeling vibration through the steering wheel, or if the sound shifts toward a grinding or clunking noise, that's a sign the bearing is progressing toward failure faster than average. At that point, treating it as urgent rather than something to monitor further is the safer approach.
If you commute daily on I-94, US-23, or M-14, keep in mind that consistent highway miles will use up whatever life is left in a noisy bearing faster than someone who mostly drives short trips around town. Two Jeeps with the same noise level can have very different timelines left simply because of how and where they're driven each week.
Rather than trying to estimate how many miles you have left, the smarter move is to get it inspected as soon as the noise appears. Hoover Street Auto Repair in Ann Arbor can assess the play and wear on your specific bearing and give you an honest sense of the urgency, so you're making a decision based on the actual condition of your Jeep rather than a general rule of thumb.