pump (abs?) coming on when wheels slip from acceleration?

[John Redcorn]

I noticed this a couple weeks ago when there was ice on the road, it seemed like if I was in 2hi and the wheels slipped I'd hear something under the hood that sounded exactly like the abs pump. it didn't seem to happen in 4wd.

Then just yesterday I was playing around in a mud-hole in 4hi and noticed the pump coming on ever once in a while when the tires were slipping. Not all the time though because I was going across that thing sideways a lot pumping a jet of mud 20 feet in the air! (yee haw!)

I'm not touching the brakes at all when this happens btw.

Any ideas? I didn't think any of these came with any type of traction control, there's no button or light for traction control anyway.

A friend was just at my house a few days ago with a tech-2 he'd borrowed from work, he plugged it in (not related to this, we just wanted to see what it said) and it showed it had "history codes" (he says codes that made the mil come on at one time) for both front wheelspeed sensors not repsonding.
I've never had the mil come on in the 6 weeks I've owned it and I've replaced one front wheel hub (includes a new wheelspeed sensor)

 

[bowtiefreak]

what year truck is it?

 

[metro273]

Sounds to me like the ABS system is doing it's job...:thumbsup:

 

[John Redcorn]

Sounds to me like the ABS system is doing it's job...:thumbsup:

I wondered, I've never drove anything that did anything like that, I wasn't touching the brakes at all.

I posted the same question on gmfullsize.com and I kinda got basically told the abs system knows the wheels are spinning different speeds (2 open diffs ) and it's kind of "getting ready" to do some abs type stuff if it needs to.

http://www.gmfullsize.com/forum/showthread.php?t=140988