4x4 problem! its not working, Please help

[krakajacka]

first off i have a 99 jimmy about 120 k

the problem being is the 4x4 doesnt seem to work

when your in 2x2 and switch it to 4x4high in neutral the light changes but you dont hear anything switching

 

but when i go into 4x4lo the light changes and it sounds like something is switching, and back from 4x4 lo to 2x2 it changes.

 

But from 4x4hi to 2x2 nothing changes but the light.

 

 

It all started when i took the truck off roading the first time i got stuck on some ice and kept on spinnin i ptu it into 4x4 hi the back kept on spinning but the front nothing then i put it into 4x4 lo still the back spinning but the front nothing. So i have no idea whats going on the light changes but thats it.

 

 

plus i lifted the truck today a bit put it in 4x4hi and the front tires did not spin just the back. didnt get the chance to check 4x4lo

 

 

please let me know what i can do to fix this. cuz winter sucks

and getting stuck sucks

 

THanks

[GM-Tech]

plus i lifted the truck today a bit put it in 4x4hi and the front tires did not spin just the back.

 

But did the front driveshaft spin? If the driveshaft was turning but the wheels weren't, then it's an axle problem... probably not engaging. If it's an axle problem, is the actuator being activated? This is a vacuum actuator that's located under the battery tray.

[krakajacka]

didnt get the chance to see if the driveshaft was spinning b/c didnt have enough support to hold it up, how would i fix it if its an axle problem, and make it engage.

how do i find out if the actuator is activated.

 

history on the truck it was in a accident in the front driver side wheel area. the control arm was bent need to change differnt parts in that area.

But its all saftied and running perfectly now. Just the 4x4 is not working

please let me know how to fix this problem.

 

sorry im not to technical.

[GM-Tech]

Put it in 4wd. Look at the actuator under the battery tray (easier said than done). I believe you can see if it's sucked in. It's a vacuum operated actuator.

[krakajacka]

is there any way to do this with the battery in and tray in?

b/c all i did to check now was get someone to switch from 2x to 4x4 hi and lo

to watch for any signs of vacum movement around that area, and no signs were indicated as well as i didnt hear any thing change in the engine bay. But when your in the driver seat and switch b/w 2x2 and 4x4lo it sounds like something is happening

[krakajacka]

ok i i lifted it up again today, when you put it in 4x4 hi or low the front tires do not turn, nor does the drive shaft, it seems like the drive shaft is a bit loose u can move it a bit to the transfer case where in the back for the rear wheels theres no give.

 

i went to the transmission shop today got an appointment for tommorw, they said might be some locking problem.

also removed the driver side headlamp to see the actuator and when i switch from 4x4 to 2x2 i didnt no see any lines move or anything.

 

any ideas

[GM-Tech]

If the transfer case is not engaging, it could be a switch or control module problem. I can't really guess at what might be wrong. Need some specific diagnostic information, like codes, etc.