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I took some advice off here and went with the Rancho QuickLift front replacements for my 15 Sierra Z71 Crew Cab 4x4, part number #RS999901- I got them off Amazon for $320 delivered. Before, the rear fender was 39.5" and the front was 36". After, the rear is 39" and the front is 38", and the front of the cab is 17 3/4", and the rear of the cab is 18 1/4". I got right at exactly 2" lift up front. I'm still playing with the settings on the dampers, but I installed them last night in 3 hours. I could've done it in about half that if I could've found my 15mm deep socket...... 5 bolts each side removed, and the long bolt on the sway bar loosened on each side and it pops right off. Ride is at least as good as the stock fronts. I am going to swap out the rears to RS9000XL in the near future. I sure like how she's sitting now. I also need t ofind the time to drop her off to get the fronts tinted....

You'll probably say that a dozen times. "done" is a fluidic word lol

Here you go, these are not the best pics but will give you a good idea on how they sit. They are about 1.5-2" outside of the fender, IMO a perfect look, I don't like when the tires are sucked in on these bigger trucks and to wide just throws crap all over the place.

So we went to the beach this past weekend to fish and crab and it was extremely overcast for a little while. I took these pictures with my iphone and i wanted to share because i thought they came out great. Note: There was no filter or editing applied to the pictures.

Yes there were a real pain in the ass.... And I had to call vled and they explained that sometimes the wires on the bottom move so I had to force them over then went under the truck and used both thumbs and pressed extremely hard and they went in and light up now... The fog lights look killer as well that I got from them but the passenger side one has me paranoid because I can't be sertain both clips clipped it was giving me a really hard time... Sent from my SM-G900W8 using Tapatalk

Perhaps you had a different experience, but I recently went through the whole process. Sure it took a couple months, but in the end I got full MSRP trade on a new truck. I drove my 2014 for over 12000 miles and didn't pay a dime for it. The BBB worked out great for me.

Fogs and license plate lights are in... My reverse and cargo should be in later this week and hid kit going in tomorrow hopefully pretty exited... Sent from my SM-G900W8 using Tapatalk Sent from my SM-G900W8 using Tapatalk

Truck went in for a oil change in the dealer followed with some brake line recall and for a werid downshift feeling and then I had to show them where the zerk points on the tie rod was they didn't even no they were there... That's comforting Sent from my SM-G900W8 using Tapatalk

It is from Grand Lake, CO

Move able parts work best if they keep moving.

^^^^^^ That would be your decision to make. A truck with 80,000 miles may actually be in much better mechanical shape than one with 25,000 miles depending on how they were treated. You are going to want to know how the truck was used and if it has been serviced regularly. Knowing that should make the decision easier when it comes time to buy. Remember that the 09-13 6.2L Sierra & Silverado did not have AFM so nothing to worry about there. Those years are GM's best for the 6.2L truck engines. The new trucks all have AFM! GM should have not messed with the 6.2L truck engine, they were perfect without cylinders turning off and on. Sent from my crappy iPhone 6 using Tapatalk

Awesome pics!

I have a 2015 Z71 4x4 CC Sierra SLT 3.42 rear end that started vibrating at about 2k miles. It has Rancho quick lift rs9000 struts on the front and rs9000s in the rear. Aftermarket wheels and toyo at II tires. After reading all the forums this is what I have done thus far trying to track down the issue in hopes of finding something that could solve the problem and possibly help others get theirs fixed as well. I used an app on my phone to use the internal accelerometer to find the resonance frequencies it vibrates at. Got a spike at 13, 26 and 39 hz at 72 mph. 13 hz is a first order vibration that matches tire speed directly, 26 and 39 hz are second and third order "vehicle speed" vibrations that could also be tire related. Had the tires road forced and 0 gram balanced 4 times. The 13 and 26 hz vibrations went away but the 39hz still remains unchanged. Could be a third order tire problem that is usually unfixable without replacing the tire. So I swapped the after markets for the factory wheels and tires. 39 hz vibration still there. Then I tried every combination of after market and factory. Took the better part of the weekend testing everything. 2 factories on the front, 2 after markets on the rear then cycled each wheel to each corner. The odds of every wheel and tire having a third order vibration is extremely unlikely which I think rules them out as the vibration source. Next step checked radial and lateral runout at all 4 corners. No smoking guns there either. Truck still vibrates from 70 - 75 mph. Tried re-settling the body mounts as posted here, no dice there either. Next step is to road force and 0 gram balance the factory wheel and tires and see if that changes anything. If not, I'm going to put the factory shocks and struts back on and test again not hopeful this will fix anything either. After reading this forum and numerous others on this issue and the problem occouring in all cab configurations in both 2 and 4wd my suspicion is that the problem is the rear end, likely a bad ring gear. The ring gear spins at the same speed as the tires, a warped ring gear or bad spots in the tooth cut furing mfg. or heat treating could cause a 3rd order vehicle speed vibration. I did some research and found out the 9.5 inch rear end in the K2XX platform is a new design, and uses different internal parts from the 2013 and older 9.5 rear ends. Even though this rear end has been out for 2 years there are no after market gear sets available for it. Is this a possible known design flaw and things may be changed so no one wants to invest in tooling???? Rebuilding a rear end with the only parts available from the same company that made the original garbage parts doesn't give me a warm fuzzy but may be the only avenue to try and solve this problem. The only other thought I have on the issue is a tolerance stack issue. Multiple items rotating at tire speed (hubs, axle shafts, rotors all technically within tolerance individually but when combined to form a rotating system cause just enough imbalance to make the truck vibrate and these new lighter stiffer frames transmit the vibrations right into the cab. testing this theory would require dynamically balancing all these parts which seems unreasonable. I'm trying to arm myself with enough data to avoid multiple trips to the dealer where they just rf balance the tires over and over before actually looking at the rear end or other drive train components as the source. I won't accept "normal operation" or "they all do it" out of a $55k truck.

2015i Sierra All Terrain HD

Just a heads up guys, running tire pressure at what "feels good" is incorrect, tire pressure is about load carrying ability. Those of you running 8 & 10 ply's at stock 4ply tire pressure are likely running below minimum requirements for the application. I run my LT285/65R18 10ply's at 52psi to maintain minimum load carrying ability. EDIT: Tire pressure is not a 1:1 equation across all sizes and constructions...

Stock tires and your tires OP are two totally different things. The door sticker will say 32psi, but you have load range E, you will want to be up around 40 at least.

So I got it back from the dealer today and was told they test drove one from the lot and it had the same vibration and possibly even worse then mine. I was told GM admits there is a problem but at this time no solution. I was told to wait until there's a solution or the problem progresses.