Hello all .... need some help figuring out what's happening. Hadn't used 4wd for a few weeks but just the other day we got alot of snow. So 4auto and 4lo work but 4hi is not working. There's no error codes, no flashing lights on the switches or dash and the fuses all look good There's an audible motor noise (almost like the fuel pump priming before starting) when selecting between 4auto,4hi, 4lo and 2wd. The axle actuator is the most reference culprit out there but why would it work with 4auto and not 4hi?

Thanks in advance for any help!

 

Just an update ..... I checked the front axle actuator and I can hear and feel it working when selecting modes. I jacked up the drivers side front wheel and put it into 4lo .... I couldn't turn the wheel so that's good. If I put it in 4hi or 4auto then the wheel will spin freely. Driving today 4auto still works great but 4hi doesn't.

At this point I'm gonna take it in to my mechanic and get them to figure it out rather than replacing parts I'm not sure about. I'll report back what the findings are.

 

Maybe this can help?

https://www.youtube.com/watch?v=Su9Dkrfd_Zg

 

Thanks for the link. I did check that out but my OBD doesn't have a connection at pin 13 unfortunately so I don't know how to check if there is any codes. I've been spending a bunch of time online researching this and I can't find an instance where someone has had a similar problem ..... most issues are vehicles without the 4auto mode and virtually everyone has some indication of something wrong on the switch lights or a dash light.

I can select 4hi and the selector switch shows it's in 4hi and I can hear the motors switching underneath but there's no power to the front wheels. Yet 4auto will work?!?!?!?!

I have a feeling it's gonna be an expensive fix!

 

Thought I'd update this with the solution. I took it in and the front wheels would spin when in 4hi but there wasn't any real power going to the front. The shop recommended replacing the front actuator which I had a look at myself and it was working fine .... as a note 4hi and 4auto had no difference on the front actuator working (plunger would come out and stay out). After doing more research I was convinced it was the transfer case motor as it does have a motor brake in it (holds the selector in 2wd or 4hi) plus a sensor. Took about 1hr to re/re the transfer case motor (easy) .... I took out the t-case fuse before doing work and did the 5 ignition on/off cycles before starting it back up (tried this previously to see if it would help but didn't). With the part switched it took a few flashes (longer to switch) when selecting 4hi than before and it works great now! Since it's warmed up here and the snow is melting I might not get much use out of 4wd but nice to know it works now.

Hope this helps someone else down the road!