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Diagnosis needed

I have a 2004 Chevy Tahoe with 129,000 miles on it. The truck runs great. I want to keep it running because my wife drives a Nissan Cube. You don’t want to be a full sized man in a sub-compact car that resembles a toaster. My truck is fine until I come to a stop. When I start to accelerate, the traction control kicks in and takes power away from the drive train. The words “traction control active” appear on the instrument panel. If I am making a turn, mostly left, but occasionally right, I will hear a rotational grinding noise. Any ideas? Why is the automatic traction control kicking in?

Traction control uses sensors, one per wheel, to measure the rotation of the wheel. If a wheel is spinning too fast or slow compared to the other wheels a computer kicks into action. Brakes are applied to bring the wheel speeds back into synch based on the programming of the computer.

If the traction control kicks in and you are on a slick patch of road, or there is a lot of dirt/sand/dust on the road then the system is just doing its job. If the road is clear and dry then a sensor is defective on one of the wheels or some other component of the system is not working properly.

Grinding noises and pulsation in the brake petal are common when the system kicks in.

The grinding noise might be from a worn wheel bearing. If the wheel bearing is worn and it causes the tone ring to become misaligned with the wheel speed sensor, this can send a false signal to the ECU causing the traction control to kick in.