Leaderboard

New to forum.. Just picked up my new truck last week. Now I have to decide what to modify to make it my own Sent from my iPhone using Tapatalk

2015 Iridium Denali Sierra with 22 inch GMC rims painted to match.Tires are Cooper Zeon LTZ's 305/40/22 no rubbing on stock suspension height.

Finally had time to build the Relay panel for accessory lighting. Built and extra for a friend. Spare: Installed:

Finally put the BFG KO2s on the truck. 275/70/18.

Thanks bud

RWL = Raised White Letters. Sent from Tapatalk App - Samsung S6

Definitely didn't make the mudflaps. They're Gatorback mudflaps. Just google gatorback black gmc mudflaps and they should come right up.

Excellent post. Thanks for the great info.

Here's my return for a run from Hampton NH to Portland ME yesterday in a double cab LT 4x4 with the 4.3l. Maintained 65-70mph with one stop along the way.

Swapped out my chrome mirror caps for Summit White ones. I thought the chrome caps were overkill. Planning on leaving the chrome trim and handles though. I really need to order my Amp steps. I hate the factory ones. I think removing them will also make the truck look much better.

I run my tires 30psi cold, no mater the ply or load rating especially on my one tons for ride quality. When I'm going to haul a load I add air pressure to cold max so the tire doesn't overheat and separate. Doing it 40 years no problems. You can run max cold pressure if you want and want to bounce all over the place, I prefer a smooth ride. Sent from my iPhone using Tapatalk

One very sharp truck....look's great!!

Only pic of mine i can come across right now, gives you an idea though. Im glad i did it

Whatever it is, has now carried itself from 2014 to 2015... Which means GM does not have the answer

bds 6" will net you more lift than the rc 6" lift. Go with the bds and don't look back, it costs more, but you get a way more solid lift and better products.

Beautiful High Country! Wish mine was a 2500HD

I loaded my truck yesterday at the Home Improvement store with a skid of River rock, and 15 bags of soil. It squatted down, but not much.

Added Rancho Quicklift struts/coils and RS9000 shocks. Just as expected, added right at 2" to the fronts. Ride at 4 front and 6 rear is firm but smooth. Very similar to factory. Before After

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.

Everybody is like I get 27 MPGs but I have only been 5 miles lol

Un-repairable flat lead to new tires:) Got a great deal on these Toyo Open Country ATII Extremes, 295/55R20. Above pic has stock tire on the front still. Way more rim protection with this width of tire.

Sent from my SAMSUNG-SM-G900A using Tapatalk

Got the tires put on a few days ago. Tires are 275/70R18 Toyo Open Country M/T. I also have a RC 2.5 leveling kit, with the rear blocks that came with the kit installed(some people didn't use them).

Waiting to add Anzo headlights and the front will be finished.

I think as long as you run any dexos 1 approved 0-20 syn, and a quality filter (ie- AC, Wix, M1 Etc) the engine oil will be the last failure item on the list IF you keep the truck that long to find out. Say you change the oil every 7,500mi per the OLM. You keep the truck 10yrs and drive like me 25k-30k/yr. So the truck will have 250k-300k in 10yrs. You'll have done 33-40 oil changes. Say the difference between running M1 vs Synpower is $10 per oil change. It's every bit of that IIRC from two weeks ago. The 5qt jugs are like $5 more for M1 @ walmart, then you gotta buy the 3 quarts which are like 2-3 more ea. So at 300k miles and 10yr later is your truck worth $400 more b/c you ran M1 over synpower? Is the engine going to be in any better shape? Even if it is, the truck is by far shot. And can you imagine the new silverado they'll have out in 2024? Need to keep things in check. And we know based on UOA's that M1 and Synpower are both top tier oils and it's a personal preference at that point. And I think Pennzoil started carrying the dexos1 on some of their oils recently too. Just run a quality dexos 1 0-20 full syn, change it per the OLM, run a quality filter and find something else in life to spend your time on.

Sent from my iPhone using Tapatalk Sent from my iPhone using Tapatalk Sent from my iPhone using Tapatalk

2015 GMC Sierra All Terrain, Stone Blue Metallic. 285/65/18 BFG KO2's 18" Fuel Assault's, +18 offset 2" Ready Lift Level. Love the look of this truck, but I'm pretty angry at myself for not getting 305's and a more negative wheel offset to give it a more aggressive look. Got 1000km on her in since I picked it up yesterday and so far there is a minor vibration at a speed of about 120km/hr. Fuel mileage so far has not been very good for me. (15 mpg all highway). I know the BFG's don't help, but I was still expecting much better. Another issue I'm having is that the speakers periodically crack at anything above half volume. Not acceptable for the so called "Bose Premium sound." Also a little irritated with the throttle lag, and the touchscreen lag. I had a short race against an ecoboost on my way home and got absolutely smoked. Besides for that, great truck so far. I absolutely love this colour, glad I held out for it!

Got the bed Line X'd today. Got the UV resistant Line X Premium from Line X of Arlington, TX. $575 OTD

My truck 7.5" rcd with 2piece fuel maverick 20x10 -19 offset on 35/12.50/20 toyo open country ..question I have is can I use the 5100 bilstein shocks on my truck and is there anything available for the front yet?

The TPMS sensor matching process is outlined below: 1. Set the parking brake. 2. Turn the ignition switch to ON/RUN with the engine off. 3. Press the Remote Keyless Entry (RKE) transmitter's LOCK and UNLOCK buttons at the same time for approximately five seconds. The horn sounds twice to signal the receiver is in relearn mode and TIRE LEARNING ACTIVE message displays on the DIC screen. If your vehicle does not have RKE, press the Driver Information Center (DIC) vehicle information button until the PRESS V TO RELEARN TIRE POSITIONS message displays. The horn sounds twice to signal the receiver is in relearn mode and TIRE LEARNING ACTIVE message displays on the DIC screen. If your vehicle does not have RKE or DIC buttons, press the trip odometer reset stem located on the instrument panel cluster until the PRESS V TO RELEARN TIRE POSITIONS message displays. The horn sounds twice to signal the receiver is in relearn mode and TIRE LEARNING ACTIVE message displays on the DIC screen. 4. Start with the driver side front tire. 5. Remove the valve cap from the valve cap stem. Activate the TPMS sensor by increasing or decreasing the tire's air pressure for five seconds, or until a horn chirp sounds. The horn chirp, which may take up to 30 seconds to sound, confirms that the sensor identification code has been matched to this tire and wheel position. 6. Proceed to the passenger side front tire, and repeat the procedure in Step 5. 7. Proceed to the passenger side rear tire, and repeat the procedure in Step 5. 8. Proceed to the driver side rear tire, and repeat the procedure in Step 5. The horn sounds two times to indicate the sensor identification code has been matched to the driver side rear tire, and that the TPMS sensor matching process is no longer active. The TIRE LEARNING ACTIVE message on the DIC display screen goes off. 9. Turn the ignition switch to LOCK/OFF. 10. Set all four tires to the recommended air pressure level as indicated on the Tire and Loading Information label. 11. Put the valve caps back on the valve stems. Just had to do this myself.