The wire on the front hub of a 2000 Chevy Tahoe 4WD is most likely the
speed sensor wire. This wire connects the wheel speed sensor (located within the hub assembly or very close to it) to the anti-lock brake system (ABS) module and/or the transmission control module (TCM). The sensor measures the rotation speed of the wheel and this information is crucial for ABS function and potentially for transmission shifting.
It's important to note that there *might* be other wires depending on specific options or aftermarket additions, but the wheel speed sensor wire is the overwhelmingly most common single wire found on a front hub.
