Stuck in 4 wheel low

[6977Gregyver]

My Yukon is stuck in 4 wheel low. How do I get it back to 2 wheel drive? 2006 Yukon

 

[Fless]

Have you looked in your owner's manual for the procedure?

 

[Scottydoggs]

mine did this once, just had to let it sit and cool off for a few hrs, then the actuator worked again, that was in the heat of summer, during winter ive never had a issue.

 

[PG01]

My Yukon is stuck in 4 wheel low. How do I get it back to 2 wheel drive? 2006 Yukon

Put it in neutral while you’re rolling foward or backwards the switch 4wd low to 4wd high…as you’re slowly moving 1-2 mph max then you should be able to go right to 2wd from there.

 

[dps01]

PG01 is correct…

What are your symptoms (dash indications)?

If there is nothing malfunctioning with your transfer case, the process is outlined on Pages 2-30 / 2-31 of the owners manual:

Shifting into 4LO

To shift to the 4 lo position, the ignition must be in RUN
and the vehicle must be stopped or moving less than
3 mph (4.8 km/h) with the transmission in NEUTRAL (N).
The preferred method for shifting into 4LO is to have
your vehicle moving 1 to 2 mph (1.6 to 3.2 km/h). Press
and release the 4 lo switch. You must wait for the
4LO indicator light to stop flashing and remain
illuminated before shifting your transmission in gear.

If the 4 lo switch is pressed when your vehicle is in gear
and/or moving, the 4LO indicator light will flash for
30 seconds and not complete the shift unless your
vehicle is moving less than 3 mph (4.8 km/h) and the
transmission is in NEUTRAL (N). After 30 seconds
the transfer case will return to the setting last chosen.

Shifting Out of 4LO

To shift from 4LO to 4HI, AUTO 4WD or 2HI your
vehicle must be stopped or moving less than 3 mph
(4.8 km/h) with the transmission in NEUTRAL (N) and
the ignition in RUN. The preferred method for shifting out
of 4LO is to have your vehicle moving 1 to 2 rnph
(1.6 to 3.2 km/h). Press and release the 4HI,
AUTO 4WD or 2HI switch. You must wait for the 4HI,
AUTO 4WD or 2HI indicator light to stop flashing
and remain illuminated before shifting your transmission
into gear.

If the 4HI, AUTO 4WD or 2HI switch is pressed when
your vehicle is in gear and/or moving, the 4HI,
AUTO 4WD or 2HI indicator light will flash for
30 seconds but will not complete the shift unless your
vehicle is moving less than 3 mph (4.8 km/h) and
the transmission is in NEUTRAL (N).

ALSO:

Excessively shifting the transfer case into or out of the
different modes may cause the transfer case to
enter the shift protection mode. This will protect the
transfer case from possible damage and will only allow
the transfer case to respond to one shift per 10
seconds. The transfer case may stay in this mode for
up to three minutes

 

[Fless]

And, yes, a fairly loud clunk is normal when the mode is changed in/out of 4LO.

 

[dps01]

And, yes, a fairly loud clunk is normal when the mode is changed in/out of 4LO.

Absolutely…

 

[6977Gregyver]

Yes I looked in the owners mabual. Thank you for reminding me! Nothing I can do to get it out of 4lo. The 4lo light stays solid and will not flash

 

[6977Gregyver]

And, yes, a fairly loud clunk is normal when the mode is changed in/out of 4LO.

I got the 'clunk' when it went into 4lo but will not come out of 4lo

 

[dps01]

Yes I looked in the owners mabual. Thank you for reminding me! Nothing I can do to get it out of 4lo. The 4lo light stays solid and will not flash

Are there any DIC messages?
Any issues noted when it shifted into 4LO?
Have you previously shifted into / out of 4LO successfully?
Have you driven it a short distance in 4LO before attempting to shift out of 4LO?

I have had this issue in the past if the vehicle was not driven after shifting into 4LO (ie messing around in the driveway).

 

[genestoy]

What always worked for me on the older Yukons was to get on some gravel road as hard surface just made it worse, then roll backwards in reverse slowly while still moving shift into neutral and then take it out of 4Lo. Might have to do it more than once but it always worked.

 

[dps01]

What always worked for me on the older Yukons was to get on some gravel road as hard surface just made it worse, then roll backwards in reverse slowly while still moving shift into neutral and then take it out of 4Lo. Might have to do it more than once but it always worked.

Agreed.
The front wheels need to be able to “slip” a bit on wet roads or loose gravel when turning.

 

[rockola1971]

At a complete stop put tranny in neutral. Then put Tcase into neutral. Then shift Tcase to 2wd,4wd HI or Auto 2wd. And dont ever think about racing the SUV in 4wd LO unless you want to pick the pieces of your Tcase off the road. 4wd LO makes a YUGE amount of torque at the wheels(At low vehicle speed), it is not designed for any form of normal use driving.

 

[ClarkGM]

My Yukon is stuck in 4 wheel low. How do I get it back to 2 wheel drive? 2006 Yukon

I have a 2003 yukon with this problem occurring intermittently. The first and most simple way to get it out was turning it off, then back on, then go into neutral and HOLD the 2wd button for 10 seconds, even if it seems like nothing is changing, hold it down. If nothing after 10 sec changed the only other thing that worked for me was popp8ng the dash cover/ face off off, removing the 4wd switch. Unplug the harnesses from the switch and plugging them back in.
I've had this problem for a while and almost always holding the 2wd button has worked, even when it seemed like it wasn't doing anything. After 10 seconds it would "klunk" out if 4 Lo. I learned that from a random comment on a forum somewhere.
Hopefully this helps. I just had this issue a few days ago and tried multiple things. Pulled fuses, disconnected battery, but the only thing that worked was removing the switch, pushing the wires into the connectors (just in case) and putting it back together. Once I turned the car back on I was able to go back into 2wd.

Usually I dont lose the lights on the switch, but I did the last time it got stuck. If I have lights, normally holding the 2wd button worked.

 

[ClarkGM]

I have a 2003 yukon with this problem occurring intermittently. The first and most simple way to get it out was turning it off, then back on, then go into neutral and HOLD the 2wd button for 10 seconds, even if it seems like nothing is changing, hold it down. If nothing after 10 sec changed the only other thing that worked for me was popp8ng the dash cover/ face off off, removing the 4wd switch. Unplug the harnesses from the switch and plugging them back in.
I've had this problem for a while and almost always holding the 2wd button has worked, even when it seemed like it wasn't doing anything. After 10 seconds it would "klunk" out if 4 Lo. I learned that from a random comment on a forum somewhere.
Hopefully this helps. I just had this issue a few days ago and tried multiple things. Pulled fuses, disconnected battery, but the only thing that worked was removing the switch, pushing the wires into the connectors (just in case) and putting it back together. Once I turned the car back on I was able to go back into 2wd.

Usually I dont lose the lights on the switch, but I did the last time it got stuck. If I have lights, normally holding the 2wd button worked.

I should have made it more clear. Mine randomly will go into 4wd on its own. I don't keep it on auto. It hasn't done it will driving. Sometimes after I start it up, it will randomly be in 4lo or 4 hi and I always have to turn it off, then on, then hold the 2wd button for way longer than you would think you would need to. The last issue I had was different. No lights in the switch.

 

[Fless]

I should have made it more clear. Mine randomly will go into 4wd on its own. I don't keep it on auto. It hasn't done it will driving. Sometimes after I start it up, it will randomly be in 4lo or 4 hi and I always have to turn it off, then on, then hold the 2wd button for way longer than you would think you would need to. The last issue I had was different. No lights in the switch.

You might want to scan for the 4wd "C" codes. Better yet, use a Tech 2 or other capable scanner to compare the "commanded" vs "actual" mode. I had success diagnosing mine, where the actual mode wasn't what was being commanded.

This could easily be a symptom of the encoder motor going bad on the transfer case. Those can be replaced as a unit, or just the internal range position sensor.

Best to get a capable scanner on it to diagnose.

 

[ClarkGM]

You might want to scan for the 4wd "C" codes. Better yet, use a Tech 2 or other capable scanner to compare the "commanded" vs "actual" mode. I had success diagnosing mine, where the actual mode wasn't what was being commanded.

This could easily be a symptom of the encoder motor going bad on the transfer case. Those can be replaced as a unit, or just the internal range position sensor.

Best to get a capable scanner on it to diagnose.

Yea I need to get the proper scanner. Will HP tuners scan for those 4wd codes? I've got HP tuners and credits still.

Some history on this yukon. When I bought it he had posted the 4wd didn't work. I did all sorts of research and bought it. He had removed the front driveshaft. Imagine assuming because it was getting stuck in 4wd.
My research pointed to the shift motor/encoder.
I tried the replacing the switch first because it's a simple thing and it did nothing so I just returned it. Then I bought the new shift motor as a whole. So the shift motor and encoder in there are only a year and a half old. Granted, parts these days aren't exactly great. On top of that, encoders are a sensitive thing.
After replacing that it was perfect for about a year. Then about 6 months ago it randomly would be in 4wd when I would start it up. All I would do is turn it off, turn it on, hold 2wd button, and it would go back into 2wd. But the symptoms are inconsistent. Sometimes it would be in 4wd hig and sometimes in 4lo. Usually 4 hi. You don't get much noise going in and out of 4Hi. But 4lo is different. You get that solid clunk.
I'm hopeful that the encoder is fine and that the switch is needing to be replaced (since it's the original one as far as I know). But either way. Since that last issue I had, then played with the switch, it hasn't done it again yet, and ice had to use the 4wd a couple times since then. It went right in the got it right back out when I needed it to.

If it does it again. I'll try to get the 4wd codes read somehow. I thought when I researched this a while back that HP tuners couldn't read the in depth stuff from the 4wd system but I could be wrong.

Thanks for the tips.

 

[rockola1971]

Yea I need to get the proper scanner. Will HP tuners scan for those 4wd codes? I've got HP tuners and credits still.

Some history on this yukon. When I bought it he had posted the 4wd didn't work. I did all sorts of research and bought it. He had removed the front driveshaft. Imagine assuming because it was getting stuck in 4wd.
My research pointed to the shift motor/encoder.
I tried the replacing the switch first because it's a simple thing and it did nothing so I just returned it. Then I bought the new shift motor as a whole. So the shift motor and encoder in there are only a year and a half old. Granted, parts these days aren't exactly great. On top of that, encoders are a sensitive thing.
After replacing that it was perfect for about a year. Then about 6 months ago it randomly would be in 4wd when I would start it up. All I would do is turn it off, turn it on, hold 2wd button, and it would go back into 2wd. But the symptoms are inconsistent. Sometimes it would be in 4wd hig and sometimes in 4lo. Usually 4 hi. You don't get much noise going in and out of 4Hi. But 4lo is different. You get that solid clunk.
I'm hopeful that the encoder is fine and that the switch is needing to be replaced (since it's the original one as far as I know). But either way. Since that last issue I had, then played with the switch, it hasn't done it again yet, and ice had to use the 4wd a couple times since then. It went right in the got it right back out when I needed it to.

If it does it again. I'll try to get the 4wd codes read somehow. I thought when I researched this a while back that HP tuners couldn't read the in depth stuff from the 4wd system but I could be wrong.

Thanks for the tips.

Are you 100% sure that when you are doing a cold startup and the indicator light is showing the Tcase in a gear you did not select before you the shut the vehicle off? Unless you have a button(s) intermittently shorting or their respective wires, it is just about impossible for the system to select a Tcase gear by itself. Are you sure that the lights are not just showing the Tcase in a gear that it is truly not in. This is a common problem with a dirty/worn encoder position sensor (commutator). Ive drove my 03 Tahoe LT down the road before and it showed it in 4wd lo which it obviously wasnt at 40mph without screaming its guts out onto the road. Running the Tcase from 2wd to 4wd HI or Auto 4wd and then back to 2wd would clear it all up.

I have seen the front axle stuck engaged even though it wasnt being commanded by the 4wd system to be engaged. This is usually a mechanical problem with the front actuator on the front axle or within the diff.

 

[GMCChevy]

Yes I looked in the owners mabual. Thank you for reminding me! Nothing I can do to get it out of 4lo. The 4lo light stays solid and will not flash

Do the lights flash when you press the buttons? When you're slowly rolling in neutral and press either 2 or 4hi that button should flash for a little bit. If it doesn't there might be something wrong with the button panel. If it does flash but goes back to 4lo being solid something else is wrong that stopped it from shifting.

 

[Fless]

Are you sure that the lights are not just showing the Tcase in a gear that it is truly not in. This is a common problem with a dirty/worn encoder position sensor (commutator). Ive drove my 03 Tahoe LT down the road before and it showed it in 4wd lo which it obviously wasnt at 40mph without screaming its guts out onto the road. Running the Tcase from 2wd to 4wd HI or Auto 4wd and then back to 2wd would clear it all up.

I experienced this exactly, too, except that I had to cycle the ignition to clear it. And it came back occasionally until I fixed the encoder motor.

Just to rule it out, you could check and clean the two ground points that are on the body mount on the frame under the driver's door hinge. One has two wires and the other has one. Don't just eyeball them, remove and clean them.