For some reason my 4WD will not disengage. Does anyone have any ideas? I would appreciate any help!

 

It could be possibly one of two things. Your AWD switch to 2WD has malfunctioned or I have seen on this forum numerous occasions people have put in a too heavy lubricant when servicing the front differential. It takes a a Type F ATF viscosity fluid as opposed to gear lube. I don't know if this applies or not to you but it is a place to start. Hope this helps.

 

This happened to my 2000 SP500 when I first got it. it was a loose conection to reverse override switch. I did not have to press it to have 4 wheel drive in reverse. The wires came apart at a plug in the headlight pod.

 

I will look at the reverse overide wires but it does it in forward as well. Do you think the overide switch could have anything to do with it in forward? I checked all the diagnostics last night including the off/on AWD switch in diagnostic mode and it seems to be working correctly. Thanks again!

 

I do not know if the overide switch is an interruptor or not. If it is, theoretically a loose wire could engage the AWD but only if the circuit was energized in the forward gears which seems unlikely. You did not indicate whether the front had been serviced recently and new diff lube put in. Last, looking at the exploded view of the front diff it could be mechanical i.e the roller cage etc. but at that point the easy answers are gone as are the fixes and you know what is left.