2016 Sierra 1500 4WD Steering wheel binding at low speeds

4emeryj44 · January 4, 2019

I did a good amount of research to see what I can find on this issue, and I came up with NOTHING for the 2016 1500. Now I did see a lot of steering issues for the 2015 trucks, which i'm ASSUMING doesn't apply to my 2016. So here we go.

I have a 2016 GMC Sierra 1500 CCSB Z71 5.3 A6 with 64,000 miles. Truck has a 4.5" CST lift with 35" tires and has had this set up for around 40,XXX miles now with not a single issue. Also, I have off roaded the truck quite a bit, but not recently. I took a trip from VA to TN which I do very often, I put a lot of miles on this truck in a very short amount of time. Just prior to the trip I had the dealer to an oil change/tire rotation as usual (BTW i'm up to date on all services, I make sure to service everything on my trucks so i'm good about that). Truck did fine on the interstate, the next day I go to drive around town and the steering wheel seems to be binding in certain spots. Felt as though the Electric Power Steering (EPS) was kind of half a$$ working, or a shaft binding, etc...… Also on the trip after driving the truck for a few more days I notice the battery guage is lower than normal, and the engine coolant temperature gauge would fluctuate ever so slightly. One day in the driveway I cranked the wheel vigorously left and right to see if I could get it to fail or throw a code, and noticed the battery gauge dropped a significant amount, to the extend of the left tick mark which i'd say was around11/12 volts. I'm thinking at this point it might be the stock battery, I've put a lot of demand on it, a lot of off roading, maybe a bad cell is causing the EPS to not allow enough current. I get back to VA and today I go to autozone to have them check the charging system, battery is good, and alternator is good. Also, no issues starting or anything just the steering binding. I go to COSTCO and get a new battery, why not since it probably needed one anyway fairly soon and I could either fix the truck or rule it out as a culprit. I replaced the battery and it didn't fix the steering issue, now when I vigorously crank the wheel back and forth the voltage doesn't drop as far, so obviously truck needed a battery anyway.

So my next thought of troubleshooting take me to under the dash where the steering column and intermediate shaft are. I notice that the shaft coming through the firewall has definite rust on it, so that caught my eye. Also, since about 6 months ago I had a noise come from the steering wheel when it's cold out but when warmer weather hits it goes away so I never thought much of it. I can absolutely hear that screeching noise from that rusted shaft. Also, I checked out the issues on the 2015 truck columns and found a service bulletin "steering column grind/pop/bind/shudder noise and/or feeling when turning 2014-2015. I found pictures that showed the lower column bearing assembly in an incorrect position (1), and/or the upper intermediate steering shaft to lower column shaft bolt and nut may be contacting the inhibitor/shifter cable bracket (2)." I checked my truck for these, didn't really seem to match as those two issues just didn't seem apparent. Although the black electrical component that goes around the shaft that has the plug going to it does make some noise when turning but I doubt that plastic is causing a major binding.

**** ALSO, I noticed on this service bulletin it said steering racks for RPO code N38 and N37, and I check my RPO code in the glovebox shows N37. Not sure if I have the updated or replaced steering column or not, couldn't find the part number on it. *******

So, here's what i'm down to unless someone has an idea of what the issue could be. Tomorrow i'm scheduled for a trans flush and fluid exchange, going to have dealer at least spend an hour trying to see if they can find the issue, see if there are any open recalls, etc.... Then i'm also going to have them rotate the tires again and re torque the wheels to see if that might be an issue of worn out tires or improperly torqued wheels as I don't have a torque wrench at the moment. Then if that doesn't work take it to 4 wheels parts where I had the lift installed and get an alignment, I did hit some pretty good potholes along the trip.

Z45 · January 4, 2019

Voltmeter Fluctuation Condition

Some customers may comment that the voltmeter is fluctuating between 12 and 14 volts on their full size pickup or utility vehicle. Starting with the 2005 model year, light duty full size pickups and utilities are equipped with a new Regulated Voltage Control (RVC) system. This system reduces the targeted output of the generator to 12.6-13.1 volts when in "Fuel Economy Mode" to improve fuel economy. The generator may exit "Fuel Economy Mode" if additional voltage is required. This will cause the voltmeter to fluctuate between 12 and 14 volts as opposed to non-regulated systems that usually maintain a more consistent reading of 14 volts. This fluctuation with the RVC system is normal system operation and NO repairs should be attempted.

4emeryj44 · January 4, 2019

19 minutes ago, elcamino said:

Voltmeter Fluctuation Condition

Some customers may comment that the voltmeter is fluctuating between 12 and 14 volts on their full size pickup or utility vehicle. Starting with the 2005 model year, light duty full size pickups and utilities are equipped with a new Regulated Voltage Control (RVC) system. This system reduces the targeted output of the generator to 12.6-13.1 volts when in "Fuel Economy Mode" to improve fuel economy. The generator may exit "Fuel Economy Mode" if additional voltage is required. This will cause the voltmeter to fluctuate between 12 and 14 volts as opposed to non-regulated systems that usually maintain a more consistent reading of 14 volts. This fluctuation with the RVC system is normal system operation and NO repairs should be attempted.

Thank you for the info, I have an idea that the truck had this, again when I vigorously turned the wheel it dropped a really good amount and thought this could be the solution, and also other gauges were fluctuation that never did before so I figured the battery was soon to be in it’s way out. I’ve seen batteries test well and yet still didn’t do well on an amperage draw so figured the electric steering was causing an excess draw due to its binding