Went fly fishing today out in the mountains, I have a new rebuild transfer case with maybe 1000km since I got it put in. Straight from gmc. So anywho I'm coming down this mountain so I pop it in 4 low and put it into second, ride down the hill, every noe and then I use first just depending on the hill I'm driving down... I get to the bottom of the mountain and try to switch it out of 4 low and the dash just flashes, .makes some electic sound but nothing, still in 4 low, 45 min later of ****ing around it finally popped back into 4hi, then I got it into 2 wheel.. all in all I think it's the switch for the dash??? It did this with my last tranfercase also on 2 other occasions. . Fishing was a blast tho

 

Following to learn what the problem was.

Do you have a 3-button or 4-button transfer case?

Congrats on the fishing! What did yoh catch?

 

4 button and a few rainbow trout

 

I'm going to try replacing the vaccume actuator also the dash switch

 

Where I live all the lakes still have hard water. The rivers are moving but so is the ice floating down them. Hopefully things will be clear sometime next month.

There is a very good step by step to diagnose your 4wd system on the site, rather than throwing parts at the problem. I wouldn't bother with the vacuum actuator, though. That only locks in the front diff and has nothing to do with the problem you had. Without going through the step by step, I'd look at either the dash switch, the tccm (module behind the passenger side kick panel), or the tcm (motor mounted on the driver's side of the tc). Those are the three main culprits that would cause your problem.

But do look at the step by step before you start throwing parts at it. It will save you time and money.

 

Is there a particular process to get it in and out of 4 low? In my Ford truck, it has to be in N with foot on brake pedal to get it into 4 low. 4 Hi at any speed and condition.

 

I believe for the truck to transfer in/out of 4-Low you have to be either in neutral or park, and moving less than 5 km/h. My understanding is also that it will not go in/out of 4-low if there's any pressure on the drive train, so moving a tiny bit sometimes helps. In my experience it actually helps to be moving slightly on level ground in Neutral when going to and from 4-low.

 

Yes you arecorrect, you need to be in neutral and preferably press the brake down, I had this issue with my last tranfercase. I tried replacing the t case motor and still had the same issue. I now have a new rebuild t case right from the dealership and this issue is still occurring. So now after posting on here I am narrowing it down to the transfer case module (tccm). When I was trying to get back into 4 hi. The light on the dash would crash for 30 seconds then you would here an odd electic motor sound coming from the passenger side dash