Transfer case will not go into neutral.

[bsamole]

Hi all, I have a 1999 Tahoe with push button 4-wheel drive. I am currently flat towing it behind my motorhome. The transfer case refused to go into neutral when depressing the two High and 4 Low buttons simultaneously for at least 15 seconds. It has worked flawlessly in the past but now it stopped working but fortunately I was able to get it back into neutral. However I'm afraid to take it out of neutral fear I won't get it be able to get it back into neutral and continue my trip.
Another symptom is the 4 Low button would not light. I was able to get it back in to neutral by backing up and going forward a few feet and depressing the too high for low buttons simultaneously. Any ideas on what causes this symptom?

 

[Bill 1960]

Most likely the actuator motor, but I wouldn’t throw parts at it without a proper diagnosis because there’s too many other potential causes. Dirty connection, chafed wiring, faulty control module, mechanical wear…

In an emergency you can always leave the truck running, transmission in neutral, transfer in 2H, and tow it that way. That will keep the trans lubricated and prevent damage. Just costs a little gas.

 

[swathdiver]

Most likely the actuator motor, but I wouldn’t throw parts at it without a proper diagnosis because there’s too many other potential causes. Dirty connection, chafed wiring, faulty control module, mechanical wear…

In an emergency you can always leave the truck running, transmission in neutral, transfer in 2H, and tow it that way. That will keep the trans lubricated and prevent damage. Just costs a little gas.

Or pull the driveshaft off the rear axle and hang it out of the way.

 

[George B]

Or pull the driveshaft off the rear axle and hang it out of the way.

Just be sure to wrap the U-joint in duct tape to prevent loosing the caps.

 

[swathdiver]

Just be sure to wrap the U-joint in duct tape to prevent loosing the caps.

I always forget that part! LOL

 

[YukonGTmaster]

I would climb underneath, and pull the connector off the 4WD actuator at the front differential. Get a multimeter, and test for 12 VDC at the connector pins while you get a helper to push the button in the cab. If you have good voltage, it is probably a bad actuator.

My actuator fried, after the connector filled with water. When I replaced the actuator, I filled the connector shell with DC4 dielectric grease, to keep moisture out. The actuator type on my 97 Yukon GT is the thermal type. You pull on the floor shifter and wait 5 Mississippi until it heats up and actuates.

 

[Bill 1960]

The front actuator is not involved in shifting the TC to neutral, though.

 

[YukonGTmaster]

I am totally out of it! I guess I just got excited when I saw “Actuator” lol

 

[bsamole]

Thanks for all of the great ideas and suggestions. I am currently in Laramie Wyoming heading to Dallas Texas. I'm afraid to put transfer case in gear until I get to the campground in Texas when I'll disconnect the Tahoe and try your ideas.