Won't come out of 4x4 mode
heathk
07-07-2009, 10:46 AM
If there are any mechanics or people that know a bit about gmc jimmy's. I
need help. Mid 90's gmc jimmy, and the problem is, It cannot be taken out of
4x4 mode. It won't go into 2 wheel drive. Have tried. So right now it is
stuck in 4x4. as well, it blows smoke that smells like sufar.
I hope someone can point me in the right direction for more answers or can
answer it here. Thanks in advance.
need help. Mid 90's gmc jimmy, and the problem is, It cannot be taken out of
4x4 mode. It won't go into 2 wheel drive. Have tried. So right now it is
stuck in 4x4. as well, it blows smoke that smells like sufar.
I hope someone can point me in the right direction for more answers or can
answer it here. Thanks in advance.
MT-2500
07-07-2009, 05:27 PM
If there are any mechanics or people that know a bit about gmc jimmy's. I
need help. Mid 90's gmc jimmy, and the problem is, It cannot be taken out of
4x4 mode. It won't go into 2 wheel drive. Have tried. So right now it is
stuck in 4x4. as well, it blows smoke that smells like sufar.
I hope someone can point me in the right direction for more answers or can
answer it here. Thanks in advance.
Put transmission in neutral and or back up and roll forward.
Have you check wiring and fuse?
What transfer case does it have?
Where is smell coming from?
Is it as burnt wire smell?
need help. Mid 90's gmc jimmy, and the problem is, It cannot be taken out of
4x4 mode. It won't go into 2 wheel drive. Have tried. So right now it is
stuck in 4x4. as well, it blows smoke that smells like sufar.
I hope someone can point me in the right direction for more answers or can
answer it here. Thanks in advance.
Put transmission in neutral and or back up and roll forward.
Have you check wiring and fuse?
What transfer case does it have?
Where is smell coming from?
Is it as burnt wire smell?
Sparky1349
07-08-2009, 11:20 AM
Heath,
I assume when you say mid 90's that your jimmy has the manual 2 wheel, 4 Hi, Neutral, 4 Low shifter on the console that you have to press the button on top to shift into 4 wheel drive mode. In addition there is a little screen in front of this shifter which has a picture of your truck and it indicates that it is in 4 wheel drive with a light. I believe that your truck has a 4 wheel drive system which is only intended to be used in slippery conditions. You don't go into much detail about what you mean by stuck in 4 wheel drive but if I had to guess I would suspect what you mean to say is that the light on the console indicates you are in 4 wheel drive even though you have moved the shifter back into 2 wheel drive. If this is accurate then the most likely problem is that the vacuum switch that is mounted on the side of the transfer case which controls the vacuum motor which activates the synchro on the front axle is stuck in the active state. If you want to confirm that it is a stuck vacuum switch look under the hood on the passengers side front inner fender there should be a round vacuum actuator about 4 inches in diameter with a vacuum hose going to one side and a cable on the other which goes to the front axle. If you pull the vacuum line off (engine off) the diaphragm will relax, if you go inside the truck and turn the key on it will show you that the truck is in 2 wheel drive. If this is what happens then you have to either leave the vacuum hose off of the diaphragm (plug the open hose with a golf tee or something so you don't have a vacuum leak) or have the vacuum switch replaced on the transfer case. If your handy you can do it yourself but you need a crows foot wrench to get it out because it is up against the underside of the floor pan and hard to get a wrench on.
Good luck,
Sparky.
I assume when you say mid 90's that your jimmy has the manual 2 wheel, 4 Hi, Neutral, 4 Low shifter on the console that you have to press the button on top to shift into 4 wheel drive mode. In addition there is a little screen in front of this shifter which has a picture of your truck and it indicates that it is in 4 wheel drive with a light. I believe that your truck has a 4 wheel drive system which is only intended to be used in slippery conditions. You don't go into much detail about what you mean by stuck in 4 wheel drive but if I had to guess I would suspect what you mean to say is that the light on the console indicates you are in 4 wheel drive even though you have moved the shifter back into 2 wheel drive. If this is accurate then the most likely problem is that the vacuum switch that is mounted on the side of the transfer case which controls the vacuum motor which activates the synchro on the front axle is stuck in the active state. If you want to confirm that it is a stuck vacuum switch look under the hood on the passengers side front inner fender there should be a round vacuum actuator about 4 inches in diameter with a vacuum hose going to one side and a cable on the other which goes to the front axle. If you pull the vacuum line off (engine off) the diaphragm will relax, if you go inside the truck and turn the key on it will show you that the truck is in 2 wheel drive. If this is what happens then you have to either leave the vacuum hose off of the diaphragm (plug the open hose with a golf tee or something so you don't have a vacuum leak) or have the vacuum switch replaced on the transfer case. If your handy you can do it yourself but you need a crows foot wrench to get it out because it is up against the underside of the floor pan and hard to get a wrench on.
Good luck,
Sparky.
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