4wd Not Engaging

I was driving today and tried putting my truck into 4wd multiple times. I tried in neutral stopped, I tried at a crawling speed, I tried at about 20mph, and each time the light would just blink and not engage. 4wd Low isn't working either. I know it's a pretty broad statement, but does anyone have any idea as how to troubleshoot it? I really don't want to take it to the dealer

 

It's a fairly common problem. If you look hard enough you'll find a thread on here where someone's posted the diagnostics for the 4wd control unit.

About the most common single failure is the actuator on the front differential. A number of members (including me) have had those fail.

Despite what the factory shop manual says - you can replace that front actuator without completely removing the front differential. You do need to unbolt and lower it, however. But you can do it without removing the CV axles, so that's a pretty fair time savings.

But poke around on TW until you find those diagnostics. Start with the "similar threads" at the bottom of this page and if that doesn't lead you to it, start searching using search words like: 4wd actuator control diagnostics

 

that would be frustrating. does the light go strait to blinking or does it "try" for a while before the light blinks

 

It goes straight to blinking. It will not stay solid.

 

Since I am under my power train warranty still, would this be covered?

 

anyone?

 

Should be covered under warranty. do you happen to have the 4x4 flaps installed? Without them 4wd will never work....

 

Haha I did... But then I got stuck and took them off... A while after they stopped. Maybe it's a sign.

 

There was a thread on here about a soderd connection in the actuator that breaks over time. Looked like a cheap fix however looked involved because you have to take the actuator out and apart

 

Bjmoose pretty much said it all. Sounds as if your 4wd actuator is done. If you are under warranty, have the dealer fix it for free then

Mine just went a few months ago as well. Luckily I was able to get it out of 4wd after messing around with a snow pile at the mall

 

Sweet! I'll call the dealer in the morning thanks!

 

Looks like this was a few months ago OP, but just curious to see what the problem ended up being? My 4WD light just blinks and doesn't engage all of the sudden.... Might be similar to your issue.... Was it the actuator?

 

Hey there. Yup. It was the ADD. Thankfully my truck is still under warranty so it didn't cost me a penny. If it wasn't though it would've been at least $500 I think.