Service 4WD

ShotgunZ71 · August 4, 2017

Got in the truck Sunday to go to church, and got the "Service 4WD" message in the DIC. It's in 2WD and the indicator light just goes off if in any position besides 2WD. I've used 4HI and 4LO a few times in the past and never had any issues. Did a quick search but the results were either for older 2500's or for 1500s. Didn't know if anyone up here has had this happen yet on the 2015+ 2500HD trucks. I do plan on taking it in soon and getting looked at.

I have it scheduled to be looked at next week. Any ideas would be welcome, though.

gearheadesw · August 6, 2017

If things are running correctly, I would say some sensor is out of whack, keep us informed, please.

Sledge8 · August 7, 2017

My old 04 2500Hd used to do this from time to time. I would guess 4-6 times in 12 years. I would shut the truck off and on restart the message would be gone and all worked as designed.

Once in a while I would also get the heater come on when it was 90 outside. Same thing, shut it off and restart all good back to AC. Haven't seen either on the new truck yet...

Damn Computers....

magnum74 · August 7, 2017

There was a TSB with something to this effect on the 1500's but not sure about the HD's. Sounds like the same problem, though. It was a switch/sensor issue and not an actual mechanical problem.

ShotgunZ71 · August 8, 2017

Hope to hear something late tomorrow afternoon or Wednesday morning. I'll be sure to share their findings.

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ShotgunZ71 · August 10, 2017

They told me they had to order a new actuator. It should be in tomorrow.

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gearheadesw · August 11, 2017

Still under warranty? Hopefully this will fix the situation.

ShotgunZ71 · August 12, 2017

Update: The 4WD Actuator was order Wednesday afternoon and was still in transit with FedEx yesterday. Hopefully it will arrive Monday and I will be able to get the truck early in the week.

ShotgunZ71 · August 12, 2017

Still under warranty? Hopefully this will fix the situation.

Yes, it's still under the B2B 3/36 warranty. At least for another year or 11k miles.

ShotgunZ71 · August 16, 2017

So, the service rep misspoke about the particular part ordered. No biggie. They had to order a new module for it. That came in and they went to program it, but after last evening and this morning, said that it wouldn't take the program. They are sending the "new" one back and having another new module overnighted to the dealer. I have the truck back now with the "Service 4WD" message and now a "Service Stabilitrak" message, as I had to have it for the next few days. They will call me when the module gets there and we will schedule an appointment to get it installed and programmed. Started to get a bit agitated, but realized that it's out of their control as far as a bad component is concerned. I truly hope that the new module comes in and can be installed and programmed correctly the first time.

ShotgunZ71 · August 23, 2017

Finally got my truck fixed. I had to take it back to them once the part came in, as it was no need for it to stay there when I could use it. As it turns out, the problem was cause by a corroded wire coming from the module. Apparently a rodent or other vermin nibbled at the insulation, possibly before I even bought the truck, and the wire finally corroded enough to break the circuit. All was repaired and it's driving like new.

Side note, a friend of mine was telling the story of test driving a new truck, and when they opened the hood they found that something had been having a field day with the under-hood insulation.

Ian Pritchard (Hydroguy8) · October 25, 2017

Had that warning on for 11 years on my '06 Silverado. Into the dealer at least 4 times-said corroded ground wire. Never did get it fixed long term. Waranty was up quick with my mileage at that time. Warning is still on, but truck still performs as it should, but is slow to engage 4WD and must shut off truck to disengage 4WDwhen it's in the Autotrack mode.

My 2015 is good and my 2017 HD is good too, fingers crossed!!

Edited October 25, 2017 by Ian Pritchard (Hydroguy8)

dpbetts3 · December 3, 2019

I also have the same issue." Service 4WD" for new 2019 GMC sierra truck .

Comes on intermittently .

Went into dealer approx. 3 weeks ago.

Told me they had to order a new actuator.( was not moving when 4WD selected)

None in stock.

Dealer said GMC has to make a new one?

Still waiting.

dpbetts3 · December 12, 2019

Still waiting

Ct1022 · January 2, 2020

2019 2500 hd service 4wd dealer replaced the actuator transfer case module transfer case wire harness and the fuse block still getting the service 4wd light intermittently