Mitsubishi Repair: 98 Montero Sport 4WD - Wont engage, montero sport, differential fluid

Question
I have a 98 Montero Sport LS 4WD.  The 4WD indicator light lights up when the truck is turned on so I now the dash light itself is okay.  I notice after a summer of not using the 4WD, the 4WD indicator will either flash constantly when attempting to shift the truck into 4WD or will not come on at all.  The truck feels like it might be going into 4WD but I cannot be sure.  The steering feel changes is my only indicator.  Working the truck into and out of 4WD used to resolve the problem in past years, is this something that needs to be cleaned or serviced?  I also have a 2003 Montero Sport AWD XLS and noticed this fall that it too is a flashing 4WD indicator but won't fully engage. Seems like the same problem.

Any advice on what to check or do to resolve this problem and get the 4WD's to fully engage when needed?  

Answer
Steven,
This may indicate a problem with the switching solenoid that is responsible for putting your truck into 4WD.  Also, having low transfer case and/or differential fluid can also cause this problem.  The flashing indicator light is a warning and usually means the system is preventing the ability to engage into 4WD for a different number of reasons.  When the truck is warmed up, you should come to a complete stop, put the gear in neutral (N), wait a few seconds, and then try to engage the 4WD.  But if the truck simply will not go into 4WD regardless of the procedure, you should have a mechanic look at it; either a transmission shop or the dealerhship.  Definitely have your 2003 Montero inspected at the dealership if you are still under warranty.
Good luck!