2014 6.2L High Country 4WD Issue

[2014MorePower]

I just had my Silverado in today and there is a techlink for the 4auto mode stay in that mode when to turn the knob back to 2wd. They tried flashing my system with it and now the noise is louder and worst off. I talked to my sale rep to have a talk with my service writer so that he would have to ride is the so called test ride the tech did and said it was fixed. The service writer could believe the noise and feel of the 4hi mode. We just took it out in the parking lot and the second turn we did he goes you still have the brake on I said look down there I don't. He said that the tech did a drive and didn't notice that because I didn't tell him it was when I was turning that it makes the noise and he only remembered the Techlink I show and gave him to help them out. He then says that there got to be a problem in the transfer case since it works in 2wd and he like the more information he got from me and the test drive. Now I have to wait for this Tech to come back from school and it would be 2 more weeks. He also said not to use 4wd because there's a problem. He did offered to try to get me a loaner when the Tech takes a look at it and maybe order parts or unit. Boy that sound like customer service one month to know that it's going to need parts. It was minus 35 degrees with wind chill this morning sure glad I bought a 4wd for winter. Also it's not a normal noise or feeling like other's have said. The GM Techlink site has a lot of problems on all their vehciles check it out.

[2014MorePower]

Well I took the truck into today and guess what they said it's normal after you get some miles on the 4wd system. I had a loaner with 90 miles on it and it ran find without the noise or vibration that mine has and the Tech said his does the same thing. The service writer said that the tech says it's normal for the 2014 when they get miles on the front 4wd system and also my tires have 1/32 wear on them. So I said why is the loaner working find and he keeps coming back to the wear on the system and tires I said you just rotated them and also mine work find when new and when I used it for less then 200 miles in 4wd mode it started making the noise. His come back was that the 2014 have this problem and the gear are turning when not in 4wd drive mode my Truck has 6156 on it and my friend drove the truck on New Years Eve and he said it sounds like it's metal on metal. So long story short is this tech won't go any further to see what this problem since his does it so call problem which I can't confirm but the one new Truck works like mine did when new and also says the wear of the tires they are round so this shouldn't be a factor I told him. He sais you got a 5/10000 warranty so just live with it because it normal for the 2014 but the inside is more quite. I told the wife I should of bought the new Challenger SRT. My friend isn't going to buy a new truck now he buys new every 2 years. I told him about this forum and all the problem these GM are having. I am really pissed off that GM isn't behind their products like the old days when my dad was a mechanic for Chevy.

[redwngr]

 

Repeat Service 4WD Message

 

September 18, 2014

 

 

Some 2014 Silverado and Sierra trucks and 2015 Tahoe, Suburban, Yukon and Escalade models equipped with four-wheel drive (RPOs NQH, NP0) built prior to September 7, 2014 or that have had the Transfer Case Control Module (TCCM) reprogrammed prior to September 7, 2014 may have a repeat Service 4WD message and one or more of the following DTCs set: C0398 (Range Actuator Position – Range Position Correlation), C038D (Range Actuator – Position Not Learned) or C0397 (Transfer Case Clutch). Typically, DTCs C038D and C0397 will be set together or DTC C0398 will be stored in the TCCM.

 

 

There also may be a binding feeling from the drivetrain on turns. If the vehicle sets a DTC in Auto 4WD mode, the default action is to move the encoder motor to apply the clutch pack, and then disable all further shifting. If this occurs, the driver may then move the transfer case shift knob to 2WD, but since shifting is disabled due to the set DTC, the vehicle may arrive at the dealership with a binding on turns condition with the shift knob in the 2WD position. (Fig. 13)

 

 

 

Fig 13

 

 

To correct these conditions:

 

 

• If the vehicle has DTC C038D and C0397 set, reprogram the TCCM with the latest software available through TIS2Web. Perform a high-low clutch reset and shift the transfer case through all ranges, ensuring that no DTCs reset and that the transfer case shifts through all ranges as expected. If all shifting is successful, return the vehicle to the customer.

 

 

• For vehicles equipped with RPO NQH, if DTC C0398 sets after being dinghy towed, refer to #PIP5217.

 

 

• If the vehicle has DTC C0398 set, inspect circuits 7477, 7478, and 7479 for any terminal or connection issues between the B2227 Gear Position Sensor and the TCCM. (Fig. 14) Repair any terminals or connectors as needed. If there are not any wiring concerns, clear the DTC and reprogram the TCCM with the latest software available through TIS2Web. Perform a high-low clutch reset and shift the transfer case through all ranges, ensuring that no DTCs reset and that the transfer case shifts through all ranges as expected. If all shifting is successful, return the vehicle to the customer.

 

 

 

Fig 14

 

 

TIP: Reprogramming the TCCM on any vehicles built on or after September 7, 2014 will not correct any conditions. Follow the appropriate Service Information for the stored DTCs.

 

 

- Thanks to Steve Schipansky and Dave Peacy