Trying to jump into 4 wheel drive

[reeltight]

2001 2500hd

This has happened enough that I’m starting to get a little concerned.

Every now and then if/when I hit a bump my front driver side hub tries to engage. I’m not certain that’s what it is but it sure sounds like it. It’s wheel specific and it’s just a grinding noise that won’t stop until I come to a complete stop. I always put it in reverse for good measure. Not sure if that does anything or not. To the best of my recollection it’s only happened my I’m turning left.

I had a 2006 F150 that did the same thing...only it did it going 80 mph down the interstate. I think the ford place replaced a vacuum breaker or something.

Any suggestions?

[KRT]

Are you applying the brakes when the noise starts?

[reeltight]

Are you applying the brakes when the noise starts?

Never really thought about that but yes...I’d say so. I’m always slowing down to turn into the drive way or parking at the dove field or something like that so yes, brakes would be applied.

[KRT]

It’s the ABS intervening.

So a bad hub, ABS sensor, or the ABS module.

My money is on the ABS module since they are known for the relay to go bad in them.

[Luvin' Labs]

And there you have it...

[reeltight]

Well...the ABS and Brake light come on as they do in every chevy of this time period.

But why would the sensor/module create a grinding sound? Or are you saying that's causing the hub to engage?

[Steelin' Ducks]

http://www.a2zautorepairs.com/

[KRT]

The noise you hear is the ABS activating.

[Gone South]

Hub does not disengage on that truck. You’re always turning your cv axles.

[reeltight]

Interesting. Guess I'm driving to Lexington in the near future.

[reeltight]

One more symptom I noticed today. Well...I'd heard this before and honestly just thought my tire was rubbing but when I heard it today I decided to get out and look. Definitely not a tire rubbing. In reverse, with steering wheel turned all the way to the left, I hear the same, but not as strong, grinding noise. This has happened with foot on and off the brake.

[Simple Man]

Do it, KRT!