service 4wd

gmguy18 · September 23, 2016

i have a 2003 chevy suburban 1500 it keeps coming up on the message ceter service 4wd and when it sits for like a few hours it will be in 4wd low i have replaced the seletor switches and it stopped the message for a few days and then it came back and was doing the same thing what is wrong with it

06pirate · September 24, 2016

Could be many things. Have it dealer-scanned for codes. It coud be an actuator or encoder motor going bad. Mine was acting similar over two years ago, and it turned out that the oil pump had worn a small hole through the X-fer case and puked the oil out slowly. My scanner is pretty good, but did not pick up the code that the dealer scanner did. By the time the "service 4wd drive" light came on the X-fer case was toast from running without oil.

Colossus · September 24, 2016

You don't have to take it to the silly dealer to have it fixed, go to a trusted/reputable independent shop and save some $$$. They have the same scan tools for those older vehicles (and quite often the newer vehicles as well) to be able to properly diagnose. As Pirate said, it could be the actuator or encoder, and ditto on the transfer case. Add to that those years were prone to transfer case rub issues (this site used to be full of posts with transfer case rub hole issues way back in the day, haha)

SpartanAutoworx · November 15, 2016

Could be a couple issues. There is an update for the TCCM Module for this particular issue but the shop will need access to sps. could also be the encoder motor ring or encoder motor.

Any good shop should be able to diag. Just let them know the switch has already been replaced.