I've had probs with my 4x4 not engaging. I checked the vac lines and replaced the vac solenoid,Didn't help.When I turn the **** to engage the light COMES ON,click in the dash,and I can here the shift motor makes noise. I took the shift motor off,marked the internals to see if it was turning when I turned **** and it is. It seems to me that the shaft going into the trans case appears to have some "slop" in it like it doesn't know where to stop in 4hi or 4lo. I turned the shaft by hand to 4hi(it's marked on the case by the input shaft) and it worked fine. I guess my question is would it be the motor if my lights are coming on on the dash or does it sound like prob in the tcase itself.I thought maybe if the motor was going out it just might not be turning it all the way to 4hi or 4lo

 

The question is are the front hubs locking in. If there was a problem with the transfercase you will know.

 

It's an 06,forgot to put that in there before. I can turn the output shaft on the trans case, the one the motor is supposed to turn, with a small wrench an it stays in 4 wheel. I just wonder how much play the output shaft is supposed to have? It doesn't really lock or click into four high or lo when i turn it by hand

 

I had that motor go out on me and the light on the dash did not come on when the motor failed. So in this case I believe it is not your 4WD motor.