Bbowen826

Mine does it as well. And it's only in the morning for the first few stops and turns. I have a Z71 with rancho shocks. First time I heard it i thought it was something moving in the bed of the truck. Then I even thought it was my ball hitch banging because it does fit pretty loose in the receiver hitch. Turns out wasn't either one of those. I've had a 2010 Silverado that had the slip yoke problem needing grease and this isnt the same. With the slip yoke it would pop every time I stopped and started moving. You could almost feel it threw the truck. It did it all the time not just in the morning. Before reading this post I was thinking a bushing as mentioned or even a caliper pin on the brakes. The whole reason I haven't taken it to the dealer is because I know they will say they can't duplicate it or can't find anything wrong. Dealerships have gotten to lazy. If their isn't a service bulletin on what the problem is they won't even attempt to figure it out.

Here are pics to show one option for running the wires threw the cap on the back of the Sierra lights. I just used a uni-bit and drilled out the center to the correct size for the grommet to fit. The other pics show how I originally had my bulbs installed which created a shadow. The next pic shows the new way I mounted them to remove the shadow. I also did a pic to show the 2 tabs you must trim if you want to move the bulb to the new angle. If you enlarge the pic you can see the red squares I used to mark the tabs I trimmed. Hope this helps some people. Old angle New angles Trimmed tabs

I wasn't even aware their was an update for these trucks already. I haven't had it done and I get 14.8 city and thats with pulling a trailer a few times a week. Ive been on the highway once at got about 19 mpg. Also got to remember you can get three different gear sizes in these trucks. the 3.08. 3.23, and 3.42. The higher the gear the worst mileage you should get. I have the 3.42 in my truck and I'm suppose to get 16 city. So 14.8 is close enough for me with pulling a trailer.