DrNick

Hey all. I know there's a ton of info out there about leveling kits for T1 trucks, but when I was researching for my truck I didn't seem to find much info on some of the options and combinations I was considering so hopefully this might help someone else in the future. * TL;DR at the bottom of the post. Here's my rig in stock trim. 2022 Limited GMC AT4. This spot isn't exactly level, but it's close enough that it doesn't register on the truck's angle sensor. I suck at taking pics, but I wanted to show the changes from the different steps of this process. Story time. I've had a 4WD GMC or Chevrolet truck (usually in Z71 trim) from each generation starting with my 1993 and they seem to be getting better with each generation. I love my 22 Limited AT4, but couldn't stand the Rancho shocks. Especially when towing. All the trucks I had before my most recent 2017 had OEM Bilstein shocks, and to me that's the feel I expect for a GM truck. I had a set of Bilstein 5100s on my 2017 Z71 which provided enough front end lift to run the tires I wanted along with handling improvements, so I knew I wanted to go that route again. In retrospect I should have looked closer at the 6112s for the front, however I'm not 100% confident I wouldn't have been in the same boat as my 5100s didn't actually provide the advertised increase in ride height (more on that later) and given they include springs it would have been more difficult to find something to pair. The stock tires also left a lot to be desired. At 25k miles they were already unreasonably loud to the point passengers would complain and they stopped balancing properly at about 20k miles. After a year with this truck I was ready for new shocks and tires. I enjoy SCCA RallyX and tow my RallyX car / gear for race weekends. The plan was not to level the truck as I wanted to keep some rake to help with towing. Since a true 33" tire wasn't available in the tire I wanted to run, I decided on a 295/70/18 or a touch over 34". I had seen some guys running similar sized tires with not much lift, so I thought I had a good shot to get by with a set of Bilstein 5100s. I also snagged a set of the Bilstein B8 upper control arms to give the best shot at keeping a decent ride and OE alignment specs. First step was the Bilstein 5100s and UCAs with the stock tires. The 5100 series claims +1.1" of ride height in the front. Unfortunately I only gained 7/8" (FL) and 15/16" (FR), but it was close enough. The rears saw negligible height increase. * Side note: previous 5100 sets ran on other trucks provided 4 different height adjustment levels, where as the current set of 5100s only have 3 (stock, + 0.5", and +1.1"). I really like the Bilsteins, but it would have been nice to get the advertised lift, and have a setting in between the 2 lift settings like previous generations which would have been perfect for me. I was also bummed about the height difference from side to side as the truck sat perfectly level prior to the change in struts, but these are small gripes. Bilstein 5100s + B8 UCA on stock tire. The Bilsteins added a noticeable amount of lift in the front along with ride and handling improvements that were immediately noticeable. They are worth the change even if you're not wanting to add any height IMO. Stock tires had to go. I've tried a few different options over the years and have had the best luck with the BFG A/T KO2. They didn't have the size I wanted, but the 295/70/18s were close. If nothing else it was nice to have a tire that balanced and wasn't distractingly loud. It was close, but they did rub a touch. It was only at full right lock in reverse, and when hitting some large bumps at speed, but I don't tolerate rubbing tires. Bilstein 5100s + B8 UCA on BFG 295/70/18 tires. In spite of the few instances of rubbing and slightly heavier tire, I really liked the strut / shock and tire changes. The tires added approximately 1 inch of overall height. The goal was to keep some rake while eliminating rubbing. I wasn't sure what I could pair with the 5100s to hit the sweet spot while staying within spec in the front, and unfortunately I didn't see many options in the 1/2 to 1 inch lift range. It seemed like most of the level kits above 1 3/4" used a combination of upper and lower spacers, so I thought that the added length of the front struts might be a possible substitute for the lower spacer. The idea being the 5100s might allow for the simple addition of an upper spacer to replicate other leveling kits. Here's the final product. Bilstein 5100s + B8 UCA + Ready Lift 1.5" upper spacers on BFG 295/70/18 tires. Driving Impressions: As stated previously, handling and overall ride are significantly improved. I had a few weeks to drive the truck with the Bilsteins and stock tires to judge how they affected things. The added height in the front from the spacers either didn't have a significant effect and/or is negated by the Bilsteins. The only noticeable difference in the tires on the road are that the new tires balance properly and are quiet. I've had plenty of experience with these tires to know what to expect. I would have liked to try out the KO3, but they're not really available at the moment. Suspension Height differences: While the truck sat level from side to side originally, there is around 1/8" of difference from the right to the left now. Due to the difference, the figures I post are the average of the right and left. All measurements were from the ground to the bottom of the fender directly above the center of the wheel. Measurements were taken before and after the tire change which resulted in an increase of overall height by approximately 1 1/8" over the stock tire. I have the exact measurements on all 4 corners at each stage and have subtracted the increase due to tires. The final product sits nearly level depending on level ground. I'm hoping for a touch of settle. - Front: - Bilstein 5100 struts set @ 1.1" lift: + avg 0.9" (29/32") over stock. - 5100s @ 1.1" + Ready Lift 1.5" upper spacer: + avg 2.15" (2 5/32") over stock. - Suspension mods + BFG 34" tires: + avg 3.375" (3 3/8") over stock. - Rear height was increased by 1.125" (1 1/8") over stock attributed mostly to tires. The current plan is to allow everything to settle over the next couple of weeks and re-measure when I retorque bolts and check the alignment. I would like to and am considering dropping the 5100s to the middle setting (+ 0.5" lift). If I do this and there is no rubbing I will update this thread in the future. There's probably much better ways to go about this, but so far so good. Hope there is some useful tidbits for someone down the line. If you got this far, thanks for reading. TL;DR - Approximately replicated other leveling kits that include top and bottom spacers + UCAs with Bilstein 5100s, B8 upper control arms, and Ready Lift 1.5" spacers. Results is an average of 2.15" of front lift allow 295/70/18 BFG KO2 tires (approx 34.3" dia) to be ran w/o rubbing. Truck aligns to factory specs, better handling, better overall ride, negligible increase in CV angle, and nothing in front end required significant tension to install.

The effect of stacking kits in my case mirrors the ReadyLift and other 2.5" lifts. However instead of the lower spacer you get the same effect from the longer strut. It has not resulted in any noticeable stiffness in the front and the ride improvement from the 5100s is significant.

Update. I ended up going through some trial and error, but finally got everything installed and I think i'm to a stable point with the truck. I ended up grabbing a set of Bilstein 5100s and a set of their B8 Upper Control Arms (very nice kit btw). Huge upgrade in both ride quality and handling even with the additional ride height. Even if you're not using the "lift" settings (BTW in previous versions of the 5100s there were 4 different height settings to choose from. These only have 3 and IMO the settings are too far apart to be helpful for my situation) the 5100s are a huge upgrade over the Ranchos. Unfortunately, I did not get the advertised 1.1" of lift at the highest setting. I saw a gain of 7/8" and 15/16" in the front, which is close but also sucks b/c the truck sat level from side to side with the OEM struts / shocks. The rear a tiny increase in height of 1/8" and 1/16". I tossed a set of BFG KO2 tires in a 295/70/18 (~34" tire) and had a small amount of rubbing. I don't tolerate rubbing tires and wasn't interested in trimming, so I grabbed a ReadyLift 1.5" lift for the non AT4 Sierras to stack on top of the 5100s. With the 5100 and RL 1.5" lift combo I ended up with a level truck and 2 9/16" and 2 3/8" of lift in the front over stock. There is no zero rubbing in any circumstance (I tried to get it to rub) and the truck still aligns to factory settings with very little force required during reinstall. Nothing looks to be in a bind, steering effort is low, axle angles look happy, and ride has been minimally impacted. This seems to be a non typical, but good combination to level the truck and the 5100s provide superior handling and ride even with larger / heavier tires. The longer shocks seem to take the place of the lower spacer w/o the negative side effects.

I'm aware of the workaround. This thread was to help the other people I saw looking for a similar solution. I'm in a position where i'm constantly being asked questions / pulled in multiple directions and would regularly forget to do that. I just wanted the truck to behave as every other vehicle i've ever owned in these situations without adding another item to a mental checklist.

Updated TSB and Idle Time-Out is finally disabled! While I don't enjoy idling my truck for extended periods of time, there's plenty of situations with my job and hobbies which require me to idle my truck for an hour or two. This has never been an issue with any of my previous GM trucks, but my 2022 Limited Sierra AT4 came with the Idle Time-Out feature enabled like many other trucks of this generation. Having failed previously to disable this setting in my truck due to it being a 2022 Limited, I gave up for most of 2023 until becoming frustrated again and resuming my search for a solution a month or two ago. I had previously found some other resources around the internet about disabling this setting with varying levels of success, but I wanted to share what I learned as it was not straight forward as it should have been. 1st the TSB: 21-NA-228 - Subject: Full Size Trucks Idle Time-out Disable. This TSB has a December 2022 update that finally includes the 2022 Limited trucks. Previous versions did not and resulted in my local dealer refusing to offer the service when I asked earlier in 2022. I would recommend having this TSB readily available when making an appointment or asking the service department about having this change made. 2nd was getting dealer cooperation. While this is a customer pay service, I've experienced hesitation from multiple dealers when inquiring about having this "feature" turned off. On multiple occasions, with multiple dealers, there was confusion that caused the service advisors to assume I was asking for the auto stop / start to be turned off which they are not allowed to do. Only after talking to a shop foreman who reviewed the updated TSB with me was I able to actually move forward. It's possible that the dealers in my area are more difficult to deal with than others, but this was my experience. 3rd was actually getting the software properly updated. I've previously seen comments where people who had this service completed were disappointed to find out it didn't work, and unfortunately I was in this camp. The first attempt was not successful. I assumed that this 2022 truck was similar to previous GM trucks i've owned with BCMs (2017, 2013, etc.), but come to find out the software changes are made remotely by GM and the settings are backed up along with all other configurations for the specific truck on their internal cloud. The shop foreman told me mine was the first one they've done, so there's likely not too many of these changes performed and I wouldn't be surprised if dealers had a bit of a learning curve with the process. They idled the truck for 2 hours after the change to confirm the setting was changed the second time. 2 trips to the dealer, 2 days in the shop, and $225 later I finally have a truck that will idle as long as it's in working order and has fuel. Hope the information and my experience helps the next guy. GMC TSB 21-NA-228.pdf

UPDATE AGAIN Took the truck in this week for service and the retrofit. No issues and didn't take very long. Everything works as I expect it to, and it's so nice to have the sensors given I have to park close to a fence. Definitely took these things for granted before.

Not too shabby for a 6k lb brick. Went from a 17 Sierra with the 6.2L and 8 speed to a 22 Sierra with 6.2L and the 10 speed. The newer truck does seem to be quicker. The 17 had a bit of a detent on the throttle pedal about 3/4 throttle that you had to push through to "wake up" the engine, but the new truck doesn't and every once in a while it surprises me.

Welcome! I have a friend with that combo on the previous generation truck with that same combo. It's more capable than the previous generations with the v8s from a powertrain perspective with good mpg. He's had good luck towing and the 6l80 transmission has done well for quite a while now. You should have a reliable truck on your hands.

UPDATE! Contacted the dealer for service and they mentioned my VIN was flagged for the parking sensor retrofit. They went ahead and ordered parts, so hopefully I'll have an update in the next few weeks.

Getting the same thing from my dealer on my 22 limited. The TSBs referenced in this thread stop at the 21 model year.

How did this end up? I've got a set of 5100s with the Bilstein B8 UCAs waiting for for install. I'd really like to get closer to 2" of lift in the front (with a little rake) and have considered stacking. Trying to determine if this puts anything in a bind or at unacceptable levels and which spacer (top vs bottom) has the least amount of downside. Would love to see some after pics and what you ended up with lift wise. Thanks!

Better off using a regular browser IMO. Welcome!

Hello! Welcome!

Welcome aboard!

Welcome!