New Member
2005 GMC Sierra Z71 Crew Cab

Service 4WD light came on.
Instead of going to dealership promptly.
Drove it for a few days. Then one day while driving around town noticed truck was sluggish, then noticed it was in 4LO
would not switch out of 4Lo. Drove to dealership and turned
the truck off. Thanksgiving EVE, so know one would work on
it that day. Explainedthe problem and service manager said it was the encoder motor and something else. bottom line about 900 bucks, without checking anything. Asked them if they could disable 4WD until they could work on truck. Tech unplugged something around transfer case under truck, ( I am nota mechanic ).
I was suppose to bring it in last week. Decided to wait and search the net. And what you know, i found MANY posts on several different forums having the same problem. Year models anywhere from 99 to 06. Many said changing the switch on the dash fixed the problem. Cheapest thing. I am worried however that waiting to take it in, i may have caused more problems, when truck swapped into 4LO on its own. I read it may be corroded wiring, or connection.
I have been a GM Man for years Chev-Silverado 90 model sold in 02, only changed normal items, brakes, plugs etc.
Had one of the first extended cabs to come out in 00, in our town, no problems. Now i buy my first 4WD, and all this electronic crap is failing. I am on my 2nd radio, and need another, dealer said they could not get another they would have to send that one off. Taillights fell out, dealer replaced
after warranty was up, did me a favor ( service mgr. ) Now at 52K mileage, the most expensive thing seems to have failed. I Have lost faith in GM vehicles and dont care to own a Ford, i am thinking Toyota, sad isn't that one would have to buy foreign just to get a quality product. What does it take to have a recall, after five years of this 4WD service light problem, you would think they would do something, instead the people that are not fortienate enough to get this problem while underwarranty have to pay. Its time GM stands behind their product. Maybe they wouldn't be losing billions of dollars a year, if they produced a quality product and stood behind it. Sorry for lengthy message, had to vent.
1. Please advise on steps i can do myself.
( I have done work on older model vehicles ).
2. Can you jump accross decoder plug like older models and
count blinks to get codes.
3. Where can you get quality replacement parts on the web.
4. Please list part numbers for switch, encoder motor, and such in case i have to change them.
5. Instructions would be greatly appreciated.
6. Any rouge websights with diagrams and instructions that GM hasn't shut down yet?

Thanks again.

P.s forgive spelling, typing in a hurry

 

52k is not an unexpected amount of time for a failure..thats what gmpp is for.you mention 99's having this problem ./.how long should gm hold have to stand behind it?..you thought the 36k warranty was ok when youbought it,plus I bet you turned down an extended warranty.
I'm not trying to attack you..I just don't understand why your so put out with the product...

 

Thanks for the response
I have owned GM trucks now for 25 years.
five total - all bought New
Up until now i have had nothing but normal wear items
replaced. It seems to me, the more high tech-electrical these trucks have become, the more they have electrical problems. The Service 4WD message is more common than not. I have only mentioned this problem to a couple of friends with GM 4WD trucks and both had the same problem.
I believe alot of the parts come from different factories, and built for GM. I think GM not only should stand behindtheir product, but take a more aggresive aproach to finding out the problem, rather than continue to change bad parts with the same type, from the same manufacturer.
You are correct, i did turn down and extended warranty, but until now never felt I needed it. Extended warranties are expensive for most middle class working people.
50K + miles is not alot to me, especially when my son and i drove my last vehicle 200K + miles with very little problems. I believed in GM products then, now I just disappointed. 900+ dollars for replacement parts and labor, again is alot to shell out. I hear that they have 100K warranty now, thats a step in the right direction. But again, lets fix the problem rather than exchange parts. How about a grace period for common problems, that in GM eyes dosn't warrant a recall. but i guess a recall on such expensive items would be to much for them to bear.