my 4x4 will flash repeatedly when i put in in 4 hi or lo but it will kick in and be in 4hi or lo but it takes a few tries for it to engage and the light still flashes. when it gets in 4 lo though it takes forever for it to get back to 2 hi like 10 minutes worth of hitting the button and it kicking back to 4lo. also when i start it it says service 4x4 any ideas on what it might be

how r u switching it back into 4 high from 4 low...if i remember correctly u have to put the truck into neutral

4W Hi can be hit about anytime, moving or stopped and in gear or out of gear.

4W Lo has to be hit from neutral and mine takes about 1-2 seconds to engage, but I only have 105K miles on her.

ya i got it in neutral and it takes forever for it to get out of or in but the light blinks even when it is in 4 hi or lo but goes solid when its in 2hi i got about 110000 on my truck.