new here. transfer case stuck in 4hi

[tomsteve]

i sure hope ya'll can help. 2000 jimmy. i got it stuck in a pretty nasty mudhole(unintentional) and had to do a lot of work to get it to this point. it was in 4hi when it happened, and now cant get it back into 2wd. "service 4wd" light is on. checked the electrical connections on the box on passengers side. checked the vacuum line under the battery tray. i can hear the motor that is on the transfer case( sounds like it is trying to work. i want to eliminate anything before going into that.
any and all help will be greatly appreciated.
i forgot to mention, it is my fiance's truck and she has been awesome through all of this, but she would really like to get her truck back!!!

 

[Molson02536]

i sure hope ya'll can help. 2000 jimmy. i got it stuck in a pretty nasty mudhole(unintentional) and had to do a lot of work to get it to this point. it was in 4hi when it happened, and now cant get it back into 2wd. "service 4wd" light is on. checked the electrical connections on the box on passengers side. checked the vacuum line under the battery tray. i can hear the motor that is on the transfer case( sounds like it is trying to work. i want to eliminate anything before going into that.
any and all help will be greatly appreciated.
i forgot to mention, it is my fiance's truck and she has been awesome through all of this, but she would really like to get her truck back!!!

Common for the vacuum switch on top of the transfer-case to go bad and will need to be replace. You can pick one up from Auto Zone or Napa for about half the price at the dealer.

Start with disconnecting the vacuum lines at the switch and see if your 4wd goes back to 2wd, if it does. Then replace the switch, takes about 30min to do or less with a common open end wrench.

When you push the 4wd to 2wd button, can you hear the encoder motor on the side of the transfer-case working???? If it is moving, then good chance that it's only going to be the vacuum switch.

Here is a link to where the vacuum switch is located on the transfer-case on the driver's side on top. Number 46 is the vacuum switch that needs to be inspected. http://www.compnine.com/index.php?u...delid=6872&capuid=1&majorgroup=04&grouptype=B

Good luck and keep us posted.

 

[tomsteve]

Common for the vacuum switch on top of the transfer-case to go bad and will need to be replace. You can pick one up from Auto Zone or Napa for about half the price at the dealer.

Start with disconnecting the vacuum lines at the switch and see if your 4wd goes back to 2wd, if it does. Then replace the switch, takes about 30min to do or less with a common open end wrench.

When you push the 4wd to 2wd button, can you hear the encoder motor on the side of the transfer-case working???? If it is moving, then good chance that it's only going to be the vacuum switch.

Here is a link to where the vacuum switch is located on the transfer-case on the driver's side on top. Number 46 is the vacuum switch that needs to be inspected. http://www.compnine.com/index.php?u...delid=6872&capuid=1&majorgroup=04&grouptype=B

Good luck and keep us posted.

yup, i can hear the encoder motor workin. so i'm off to see about the vacuum switch.

 

[tomsteve]

that looks like a challenge to get to. looks like i might have to add a few joints to my arm. i'm off to check it out.

 

[tomsteve]

okay, i ended up breaking the housing that the vacuum hose went into, but i got the vacuum hose off!!! i went for a ride and it didnt work. what i then did was push and hold the 2wd button, then the lights for the 4wd went out. it came out of 4hi. i could tell by doing tight circles in a parking lot down the road. when in 4hi, it acted, well, like a truck in 4wd doing tight circles. then when the lights went out it moved a lot freeer doing a tight circle. when i shut the jimmy off and restarted, the 4hi light was back on and back in 4hi. i pushed tinkered with pushing the buttons for a bit, while in neutral standing still and while rolling. the 2 wd light came on and has stayed on. it seems to be in 2wd now. does this still sound like the vacuum switch still?

one more thing, where am i going to be putting the open end wrench to take this thing off??? i cant really see too good up there.

 

[Molson02536]

okay, i ended up breaking the housing that the vacuum hose went into, but i got the vacuum hose off!!! i went for a ride and it didnt work. what i then did was push and hold the 2wd button, then the lights for the 4wd went out. it came out of 4hi. i could tell by doing tight circles in a parking lot down the road. when in 4hi, it acted, well, like a truck in 4wd doing tight circles. then when the lights went out it moved a lot freeer doing a tight circle. when i shut the jimmy off and restarted, the 4hi light was back on and back in 4hi. i pushed tinkered with pushing the buttons for a bit, while in neutral standing still and while rolling. the 2 wd light came on and has stayed on. it seems to be in 2wd now. does this still sound like the vacuum switch still?

one more thing, where am i going to be putting the open end wrench to take this thing off??? i cant really see too good up there.

It can be done, i used to change mine every 3 years before i changed my transfer-case to a AWD transfer-case. It's a PINA but it can be done with little turns and flipping the wrench back and forth.

Keep me posted and we can go from there. Here is a link she should help you, but i don't think you have the same issue. There is the procedure on how you can retrieve the DTC codes to your 4WD system to help you address the issue that needs to be replaced or repaired. http://gmcowners.com/gmc-forum/showthread.php?t=14184

 

[tomsteve]

man, i cant thank you enough for the assistance. luckily, i am mechanically inclined to a point. i gotta print those pages off and do some studying. but tonite, i am taking a break from that and going over the truck with a clay bar, polish, and wax.

 

[tomsteve]

okay, i'm back. i havent had a chance to do the DIY TCCM codes yet, but have found out that even though the 2wd light is on, the front axle is still locked in 4. vacuum problem there?? i did buff/polish the truck with compound, polish, glaze and wax and my honey is happy with that!!!

 

[Molson02536]

okay, i'm back. i havent had a chance to do the DIY TCCM codes yet, but have found out that even though the 2wd light is on, the front axle is still locked in 4. vacuum problem there?? i did buff/polish the truck with compound, polish, glaze and wax and my honey is happy with that!!!

Front axle still locked would indicate a bad vaccum switch on top of the transmfer-case that needs to be replaced. Good luck and keep us posted.

 

[tomsteve]

okay, posted about water in the trans and the solution.also was able to get the vacuum switch replaced. yup...not fun. time consuming without dropping the transfer case, but it is possible! all is good now and my girlfriend is a happy camper!!!