Service 4WD

05ChevSilverado · June 14, 2015

I just bought a 2005 Chevy Silverado LT crew cab 4x4 5.3L with 117,000km. Today the "Service 4WD" came on twice. I would turn off the truck and start it back up and it would go away for a few minutes of driving then it would come back on. I'm in 2WD, the light indicater is lit up on the 2WD switch. Is this something serious? Could it just be a blown fuse or something? Any help would be greatly appreciated.

gmtech4 · June 14, 2015

That message means there is a code in the TCCM to pull and have diagnosed , not a job for a veh owner imho

"Just bought" from where? Warranty ?

I'd be talking to them about it .... As in they PAY to fix it

DareDog · June 14, 2015

It could be switch button ( 2wd, 4x4 high low) on side of dash. Encoder motor or switch in encoder motor. Had same thing on 05 here and got it scanned. Found out it was encoder motor

Nanotech Environmental · June 15, 2015

Mine does that every once in a while & has for years, especially in Winter. Like daredog said, it's likely the encoder motor or actuator is sticking a bit, or something similar. Try cycling it in and out of 4wd a few times, especially after the truck has been driven a bunch and everything is nice and warmed up.

If you're competent with car repair, you can replace the problem items yourself. They can be bought cheap at RockAuto.

jimlem · June 16, 2015

I just bought a 2005 Chevy Silverado LT crew cab 4x4 5.3L with 117,000km. Today the "Service 4WD" came on twice. I would turn off the truck and start it back up and it would go away for a few minutes of driving then it would come back on. I'm in 2WD, the light indicater is lit up on the 2WD switch. Is this something serious? Could it just be a blown fuse or something? Any help would be greatly appreciated.

Right below your post is a reply by govtech4. Listen to him. He's forgotten more about your truck than you'll EVER know.

Comforting to see your posts again Rob.

gmtech4 · June 16, 2015

Right below your post is a reply by govtech4. Listen to him. He's forgotten more about your truck than you'll EVER know.

Comforting to see your posts again Rob.

Ty , I haven't left , did you just come back here then ?

kstruckcountry · June 17, 2015

This thread reminded me that mine just threw the same code, followed by showing neutral on the switch even though the xfer case was obviously in 2hi... Off to someone with a snap-on!

05ChevSilverado · June 19, 2015

I just don't know what is causing it. The service 4wd light can on on Monday, I turned off the truck let it sit for about 20 minutes then started it back up and the light was gone. I drove it the rest of the week with no service light on until today it came on again so I did the same thing (shut the truck off let it sit for a bit then start it back up) and light is off again.

Mason979 · June 19, 2015

I had the same problem on my silverado and it ended up being the switch that was causing the light. $40 off eBay.

gmtech4 · June 20, 2015

I just don't know what is causing it. The service 4wd light can on on Monday, I turned off the truck let it sit for about 20 minutes then started it back up and the light was gone. I drove it the rest of the week with no service light on until today it came on again so I did the same thing (shut the truck off let it sit for a bit then start it back up) and light is off again.

Scan it and have the code diagnosed OR throw parts at it and pray for accurate shot gun auto repair !!!!!

Your choice bud

gmtech4 · June 20, 2015

I had the same problem on my silverado and it ended up being the switch that was causing the light. $40 off eBay.

This is not HIS problem thou , so don't tell him this , he may do it !!!! We don't know how desperate he is !!!!

Never ever guys tell anyone " what you did "

Not cool IMO

Make sense ?

Mr.1500hd · June 20, 2015

Same thing is going on with my truck. I have the 6.0. I replaced the switch already, but it's continuing to come one. Today it came on 2 so far and yesterday it come on twice...if I hook up the scanner to it will it tell me what exactly it is?

gmtech4 · June 20, 2015

Same thing is going on with my truck. I have the 6.0. I replaced the switch already, but it's continuing to come one. Today it came on 2 so far and yesterday it come on twice...if I hook up the scanner to it will it tell me what exactly it is?

No , the code has to be followed , there are several things being checked during diagnoses of the code

Mr.1500hd · June 22, 2015

So I've already replaced the switch on the dash and my transfer case was rebuilt back in march. Is there a sensor that needs to be replaced? I also read that the ground for the switch could also cause the switch to go bad since it wasn't grounded correctly

06pirate · June 22, 2015

Get it scanned like govtech4 says.

A few months back I had similar symptoms, turned out the transfer case oil pump was eating into the case and sending metal throughout the innerds. It digested itself enough that it finally came apart about a mile from my house and I was able to limp it home, although it sounded rocks in a blender. Very glad it didn't happen out on the logging roads I take to go hiking, etc. T-case was so far gone it wasn't economically repairable. Got a new one. Not cheap. And yes, it did have stored codes, and no, I never got it scanned, just kept putting it off until it all blew up.

It "could be" a lot of things, but tossing switches and actuators at it without a scan is not the best way to troubleshoot.

My truck is a 2006 Sierra SLT X-cab, had about 140,000 miles when this happened.