2002 Silverado - Issue with 4x4

[Smitty00Z71]

I have a 2002 Silverado 4x4. I realized the 4x4 isn’t actually working. I push the button and the 4x4 switch blinks for a few second and you can hear and feel the actuator click in below. Then it lights up in the proper 4x4 mode just like it should. All indications appear that it’s working… but it’s not. No service 4x4 codes or anything.

 

What should I check? Also the ABS light is on in the truck…has been for a while. I read someone that this can cause the 4x4 not to lock in ??

[hockeypro1411]

The ABS light could just be dirty sensors. Give everything a good wash and see if the light turns off. Happens to me all the time. Someone with more knowledge will hopefully correct me if I'm wrong, but I don't think the ABS light is related to the 4x4 not working. Try engaging the 4x4 while rolling slowly in reverse. That'll sometimes do it.

[Smitty00Z71]

thanks... yes, I read somewhere about the ABS light could cause and 4x4 to not work. I just need to confirm ... and see if I can override the ABS somehow.

When I hit the 4x4 switch it makes a the classic sounds underneath and the light switches over… So I guess the actuator and switch are ok.

[Smitty00Z71]

Another thing… just went out and turned the front drive shaft… spins freely in 2hi like it should. Switched to 4L and the driveshaft locks down like it should. Again… everything seems to be working… just isn’t. I didn’t find out until yesterday when I got stuck… and couldn’t ever get the front tires to spin.

[SILVERADOSC540]

I had a '98 blazer that the four wheel drive went out in. Turned out GM mounted the hydraulic lines too close to the exhaust from the factory and they melted, dumping out the fluid. They tried to charge me for it. Crack heads. One call to GM fixed that.

[kstruckcountry]

Is your axle actuator working?

[Smitty00Z71]

I jacked up one front tire….. hit the 4hi button…. Then turned the tire. It was a harder to turn the tire once locked in 4x4… but the front drive shaft DID spin like normal....so it's locking down the axel. Same thing with 4 L….

 

So my actuator is ok? I can hear the motor working under there… and it's locking down the axel. I'm guessing the issue is with the transfer case motor found here http://www.summitracing.com/parts/RNB-600-901/

 

thoughts???

[kstruckcountry]

Yeah if the driveshaft is turning if you turn the wheels when it's locked in it's probably a t case issue

[Smitty00Z71]

Update – just to be sure I pulled out the actuator out of the front axle to check it…. It is extending out like it should when I put in 4x4 mode…. So I’m thinking I need to change the motor on the tcase