hey i just bought an 05 gmc jimmy and I have an issue with the 4wd. Its auto with the 3 button, it will engage and click. 4lo works fine, 2wd works fine, but 4wd feels like there is a problem.

like all auto vehicles, when in drive the torque makes you move without pressing the gas. Well when i'm in 4hi and i press the gas lightly it won't budge, i have to give it a bit more gas and the front or rear tires chirp. it feels like the brake is stuck, but its not. i cant really explain it well i was wondering if anyone had a problem like this?

 

Mine seems to take more to make it move in 4wd. Your moving that extra set of wheels. 4lowhas a lower ratio so its going to move of course easier than 4 high.

 

define "a bit more gas", give an average RPM that the truck starts to move at. as for the "chirp" from te tires, the only time i've ever heard my tires chirp in 4WD is when i'm on a dry parking lot doing a tight turn.

a bit more info, or a more in depth description would be helpful.

 

Sorry

Alright, I'll drive the jimmy in 4hi. I keep my foot steady on the gas, around 2000rpm it starts to slow down like the brake is engaged. I'd have to gas it to about 2000rpm-2500rpm and my front left tire will chirp and the jimmy will "unlock" itself and drive normally again. then will happen again.

also happens when i'm about to park in a stall(turning left or right into). wheels lock up and i'll have to give gas to move making the front tires chirp.

 

forgot to mention i tried this on dry pavement and is it normal for the front to bind on dry pavement?

 

Definitely normal for it to bind when turning in 4wd on high traction surfaces.

Does it bind when going straight?

 

that's what i was trying to figure out, since he also said;

so it does sound like it's happening when driving down the road, although he doesn't give any indication of his speed.

it sounds like he's having an issue with the "Auto" part of his 4WD system.

have you tried pushing the "Auto" button on your dash? i believe this is how you turn "off" the "Auto" part of it (the light should then go out).

i've never worked on this system before, my truck has the "normal" (and much more enjoyable, IMO) 4WD system. i'm sure Kyle will correct me if i'm wrong about how it operates.

please correct anything i've described, in regards to what is happening with your truck.

 

old skool luver: i don't have an auto button, just 2, 4hi, and 4lo.

Im going take the Jimmy for a spin and see if it binds driving straight and i;ll record the speed/rpm if it does. Just at work right now.

 

Everything he's indictated so far sounds about right..
Its binding while turning full crank which tells you that your obviously having a fully enguaged front end. No vac issues ect.
The only things thats odd is how high its revving before he starts moving but that doesn't sound too far off.

 

[quote=frisco204;274104]old skool luver: i don't have an auto button, just 2, 4hi, and 4lo.

see, when you don't properly write out what you have, it comes accross wrong. you should've said, "auto trans with 4WD". without using the proper punctuation-and mentioning the amount of buttons on the switch-will lead to confusion (which made it sound like it was the auto 4WD system).

so just to clarify, your truck has an auto trans, with normal 4WD, right?

all of these problems, you haven't indicated if you purposely put it in 4WD, and didn't realize this is how 4WD reacts to drivng on the street, or......if the system simply won't disengage for you. what light is on in the switch?


no, he is moving. see..........