DHC331

UPDATE: 8/17/2017: Ever since I initially engaged the 4 wheel drive in 4 high briefly and back down to 2 high several weeks ago, I have not had the noticeable tugging in the steering wheel. I do however, feel like I have to fight more with the steering. In which, I mean I have to keep both hands on the steering wheel because I feel it is swaying lightly. The sway is so minute however, I cannot tell if it is me imagining it or the road I am on. With that being said, there are other times that I feel the sway isn't there on the same roads. I have a feeling that it has to be with this newer 4x4 front end design. The older, most known design is the solid front axle but with this truck it is a differential that has driveaxles like that of a front wheel drive car. I believe they did this to give the truck excellent turning capabilities. I have a hunch that it is an honest to goodness engineering defect in the tolerance of the machined driveaxles. I suspect that it is rubbing, rubbing inward or trying to put itself into 4x4 mode on the passenger side without physical engagement of the 4x4 shifter. The reason I decided to try engaging and disengaging the 4x4 and the reason I suspect an engineering flaw is because someone told me that their newer 4x4 Chevy Colorado has a sporadic 4x4 engaging problem that the dealer cannot find. This person stated that, not always, but sometimes, if he turned the steering wheel hard enough in which he could hear and feel it hitting the max turn position, that the 4x4 would engage into 4 low. I hypothesis that the driveaxle or driveaxles are forcing their way into 4x4 mode at max turn radius and it is the 4 wheel drive low light coming on his electronic turn button control as a response to the system engaging and indicating that he is in 4x4 mode; not the turn button itself causing the deliberate normal operation of 4x4. This person I trust because he has higher, more consistent capability of observation than the typical person. Since my truck is so long, I often hit max turning position. I am currently working on a way to see if max turning radius with variables will cause the problem to reappear. I.E. flat surface max turn; mild to heavy grade max turn (on hilly driveways) going up or going down; right max or left max, etc. I going with an assumption that the max turn radius is re-positioning the passenger drive axle in such a way that at the right rpm and right speeds, it is attempting to engage 4x4, however it is luckily only rubbing, thus steering wheel tug and not engaging as I suspect if it did, it might flip the truck and or exploded the front end.

In reply to: "If it pulls to the passenger side, the problem lies in the drive train on the drivers side. If you slam on the brakes the truck stops straight with no lock up?" -With hard to severe braking, the truck stops straight and has no lock up.

Here is an update: While going down a straight, dry road around 40 MPH, I put it into 4 wheel high for approximately 15 seconds and then put it back to 2 wheel high. The shift was smooth and no problems. After I did that, I drove for a week and have not had the tugging. I will continue to update for the next three weeks. With this new information does that help you guys diagnose?

Problem: Truck while in 2 wheel drive will sporadically and temporarily tug briefly to the right causing a noticeable pull in the steering wheel to the right. It is only noticed between the speeds of approximately 40-50 MPH. There may be tugs at lower speeds but it is too small to be certain. The tugs do not occur over 50 MPH. The issue cannot be reproduced by the driver. There can be one tug or two to three sequential tugs. The vehicle is problem free prior and after the tugs. The force of the tugs can be mild, moderate or heavy. The tugs are noticed daily closer to the 42 MPH and 50 MPH marks in higher gear while coasting without acceleration or deceleration. For example, truck is accelerated to the 40-50 MPH range and acceleration is softened to allow for coasting in that speed range; the transmission will typically be in a lower gear, higher rpm, for a few moments until it up-shifts to the next higher gear and lower coasting rpm; the sporadic tugs are typically noticed in the lower gear, higher rpm range (1650). It seems that maybe the tugs are more prevalent during the first 5 to 10 minutes of operation from a sitting, parked position (cold engine or hot engine is irrelevant, it appears). Weather and pavement conditions do not affect the problem. Truck tracks straight when not tugging to the right. Problem started around 24,000 to 25,000 miles. Vehicle: 2015 Chevy Silverado, 2500 HD, WT, 6.0L Gas, manual 4x4, dual cab, long bed, tow package, plow package with 26,000 miles currently. Troubleshooting done so far by dealer: (1) corrective alignment; (1) alignment check after corrective alignment; tire rotation; swapping the two tires in front right to left; suspension check; front brake removal, check and lubrication. The dealer is currently stumped. Summary: Dealer has checked for radial pull, mis-alignment, tire pressure and brake issues. The closest guess that I have is from someone else's thread of: passenger side CV shaft going bad. They had what appeared to be the same tugging issues and the CV shaft did not give the tell-tale audible noises of failure. Their passenger side CV shaft just went bad, they changed it and posted that problem was mostly likely solved. I don't know though. Any thoughts??