2004 Z71 4x4 problem

[bsuqb1]

Hi, I have been having trouble with my 4x4 system the last few weeks. It initially started with the dash control randomly blinking to the various

settings. Sometimes auto 4x4 or 2, 4 or 4. I took it out and cleaned the connectors and it seems to have solved that problem however, I now notice that when I push it into anything other than 2 a loud "winding" for lack of a better word is coming from the front end. If I push it back to 2 It seems to stop. For some background I keep it in 2 all summer (about a month it seems here in Michigan) and in Auto 4x4 for the winter months unless roads are really dry. I had my 4x4 serviced around the 90K mark and I currently have 155K on it.

Any thoughts...

Thanks in advance

 

[zora]

Do you hear the noise only while moving?
If you hear it while standing still have you tried to locate the source of the noise?
There typically is a vacuum or electric actuator in the front that engages, try to see if the noise is from the actuator.
Any check engine lights on?

 

[bsuqb1]

Do you hear the noise only while moving?
If you hear it while standing still have you tried to locate the source of the noise?
There typically is a vacuum or electric actuator in the front that engages, try to see if the noise is from the actuator.
Any check engine lights on?

I only hear it when it while driving. If I speed up the whine increases as well. I have had a check engine light on periodically for probably 50K miles and it hasn't corresponded to the 4x4 problem.

 

[zora]

you need the codes read. If you have a minor code and ignore and than something more important occurs you will never know it since you are ignoring the light.

 

[BeachBourbon]

The 4x4 switch is notorious for going bad, but is any easy fix you can do. The part is approx 40 bucks on rock auto. This may not be the prob, but I would consider this before more expensive options. I have also heard keeping these vehicles in auto 4x4 can be very hard on the system and lead to parts failures.