i have a 2007 silverado half ton with the 4.8l v8. its just my personal vehicle so i do little to no towing or hauling with it. the other day though i pulled down in this ditch to go talk to this guy out in the field. i tried to back up the same way i came down and it spun out a bit in the grass. so i put it in 4 wheel drive and tried again but it just had no power to pull itself up. its like there was something cuttin it out. i turned off the traction control too and it didnt help. its not like i was hung up on anything or that the ditch was even that steep. i had to drive down and take a good run at it. im sure there is some feature on this truck that is to blame. i was wondering if anyone knew what this could be and if they knew how to disable or override it.

 

I'm guessing that your 4x4 just doesn't work? What about your tires. If they're balled, then that'll make a world of difference.

 

just put on new tires a few weeks ago. and the four wheel drive definitely works. its been really wet in my area this year. i've had the truck in the mud and all four tires spin. its just as soon as they start to spin there must be something that cuts out the engine to prevent spinning but there has got to be a way to cancel this because how can you budge if you have no power from the engine. i had a sunfire that used to do the same sort of thing if the tires would spin on snow or wet pavement. you could shut this off with a button though. i think it was called "ETS." some sort of traction control anyways. i know another form of traction control on other models works with the abs. if the tires start to spin out, the abs sensors pick this up and pulsates the brakes gently to slow them down. but regardless, my truck has a button to deactivate the traction control too, but it only disables it to a certain extent. it doesnt actually fully disable it and i think it has something to do with this. maybe there is a fuse or relay or something that could be pulled but i dont like to mess with the electronics. not my strong suit.

 

I guess it could be your antilock breaks? Is your check engine light on? I suppose it could be MAF related. What does the truck do under heavy acceleration in 2x4 mode on dry pavement?

 

Also maybe it's that you're in 4L instead of 4H. 4H is probably what you'll want if you're going to be driving on the road. 4L is for more torque while you're stuck in the mud or something like that.

 

4 lo will limit alot of stuff it gives you more torque then speed
anyway 4 hi is when your driving in wet or snowy conditions
4 high will allow you to shift thru all gears 4 lo shouldnt let you go past 1st or 2nd

if it were me i would start with the abs then i would look at the 4wd switch and actuator and i would make the suggestion to read the owners manual if you have one
especially the part about driving in 4wd
im not saying that you dont but its got some helpfull stuff in there about what does what
also when your engeaged in 4wd your abs shuts off at least in my 94 does then when i go back to 2 high the abs works again
i used to spend alot of time wheeling and getting stuck and unstuck and pulling people out
back when i could afford to spend money on parts to fix the 4wd system stuff is to wexpensive now for me to beat the ol girl

 

no abs or check engine light on. the abs is working fine. i dont have the electronic 4x4 switch, just the manual shifter on the floor. on my truck the abs doesnt deactivate when i have it in 4 wheel drive. in2x4 mode on dry pavement, as long as the tires don't spin out or the traction control is off, under heavy acceleration the truck performs very well. takes off like a shot and hits its higher rpms like expected.

 

Does your truck have the stabilatrac? to turn it off hold your traction control button for 6ish seconds to turn it off, that might help