I have a 09 Laramie 4x4. It will engage 4 Auto and 4H but when I attempt to select 4L, the 4x4 low light on the dash flashes and I can hear the actuator moving under the front, but it keeps moving back and forth and never engaging. I've tried doing it in park and in neutral, and also with a slight roll (5mph or less) with no joy. Also, at odd times, the SVC 4WD light on the dash will flash erratically. When that happens, I notice that the small light beside the neutral button is on and orange. Usually, when that happens, I stop and cycle through the 4wd positions that will engage, sometimes moving the truck a bit, and it clears things up for a while. This only happens only once a month if not longer intervals. Reading other forums, I haven't seen anyone with the same issues and I'm not sure if I should be looking towards the switch, the actuator, or something else and without more information, if I do have to take it to a dealer, I wouldn't know if I'm getting a rip off or not. Any help or ideas would be appreciated.

 

It's an '09. Hope you got the lifetime power train warranty. If so take it to the dealer with a $100 bill and let them fix it.

I've got an '09 also, never had that issue with mine although I have only used the Lo setting a few times.

 

My 2008 is a total B*tch to go into 4Lo. Takes forever. I only got it in once, and it was really harsh when it disengaged(I was in my driveway so it didn't surprise me too much). I tried again a few years ago and it didn't engage at all. Well, I cant say I tried all that much, but more so making sure things worked. It pissed me off so I just wrote it off as good..lol I never tried again nor worried about it because I have zero use for it.
I think what I had to do was barely get moving 5mph and put the truck in neutral, then engage 4Lo, shuifted the trans back in drive and moved forward 2-3 tire reviolutions which is like 30ft before it would engage. I had to go in reverse to get it to completely disengage. Was a PIA.

My 2000 Silverado had push button 4wd and it was as much of a pain as my current Ram.
I currently have 15,300miles and underneath is spotless. I doubt there's any actuator issue's. The T-case fluid was changed at 10kmi as well and was in perfect shape on its way out. 4Lo just needs to line up the gears perfectly in order to engage. That or I just dont know wtf I am doing with 4Lo

I am not sure what could be the blinking light issue. I would check the connections because moisture can give you intermittent malfunctions. Unplug the connectors and check them. Use so dielectric grease and plug them back in.

 

Strange, had to use mine for the first time in Nov. Engaged extremely easy. Sounds like you have issue with that xfer case shifter.

 

When I first got the truck (bought used in 2012) 4x4 worked fine in all ranges. Just started acting up last year. The times that I did use it before wasn't for heavy workload, mainly just put it in 4low to move things around the yard so I wouldn't spin up the grass in soft ground. Then, the intermittent svc light started to come on from time to time and won't go into 4low now.