Supercup

From the ground to the bottom of the diff skid plate is only 8" - that is the low point which is the front edge - it slopes up as you move back. That is with stock Duratrac 275/65/18's on Method 18x9 wheels. GMC specs for AT4 front clearance is 10.12" for AT4 and Denali - mnot sure where there measure too but you are giving up some clearance for sure. As you can see in the photos I have already hit a few things with the skid plate. I don't think 17's will work - they won't clear front brakes calipers on the truck. The Tie rod from BDS will interfere with wheel, unless you move wheel out with 0 ot negative offset. You can avoid 20's but 18's are probably as small as you can go. Front diff skid plate clearance 8" of ground clearance from front lower edge of skid plate w BDS 2.5" lift and OEM 275/65/18 Duratracs Front Caliper clearance on 18mm offset Method NV 18"x9" wheels

I could be wrong, but my buddy works at K&N and he told me they make the filter for GM, just like the K&N filter in my 2015 Z/28.

I have a 2020 AT4 Carbon Pro with tow mirrors - camera down the side works when I am towing only (trailer plug trips it). I read on 2021 it may also work without trailer - which would be nice - as you can see great down side of trailer. I have 24' that is 8'6" (102") wide and it makes a huge difference in visibility - when turn signal is selected, you just see that see that side on the entire screen.

Why do you feel it is not worth the price tag? It is not cheap but the exhaust with the CAI offer fully factory engineered and backed parts, K&N filter, better sound, better flow and a new factory tune tying it all together. It makes a legitimate 15 hp and 9 ft.lbs. of torque over stock set up (link: https://www.gmc.com/gmc-life/trucks/sierra-at4-off-road-performance-package) - so unless you want more sound - what is not to like, other than maybe the OEM pricing! Fully engineered OEM system that makes real power - that is a good combination in my book. I have it on my 6.2L AT4 and find the total package a pretty good deal.

On wheels - had I known when I bought mine I would of purchased a wheel with 0 offset or a "slight" negative offset - would try to stay -18mm or less so they don't stick out too far. I just did not know and the supplier said your stock 18's are 26mm offset and these at 18 mm were be perfect and for the Ready Lift SST level kit I did to my 2019, the were fine - but for the BDS/Zone lift not the right offset. I always want to find the right wheel and avoid spacers or wheel lug extensions - but since I had the wheels and the stock 18's would not work for sure - I went with the extensions until I sell the OEM wheels, then I will get new one's with proper offset and then sell these to someone just staying stock or doing a level. Knowing where you want to end up, at the beginning, is important, otherwise you will buy parts you can't use as you progress. But live and learn . Good luck with your set up, truck will look great and Fox 2.0's will be very nice upgrade to stock Ranchos. Not bashing the stock Rancho's the GM engineers set them up very nice to meet the needs for most on road folks and for light off road duty, which most of these trucks will never see (just like the Raptors). They are a $90 shock, so they can only do so much - the Fox is a big upgrade, but you have to pay for that!

I have 2020 AT4 with BDS 2.5" lift with Fox 2.5 adj. coilover up front and Fox 2.0's in the rear. I tow a lot - I use load level hitch and sway control to take care of tongue weight and sway issues. Air bags are not needed. If you have 1,200 lbs or less tongue weight this is all you need - if you go over that then you need to upgrade your rear springs with either a sumo spring (economical route) or a new Deaver spring 10 pack. The 2.0's are great in the back for towing - the 2.5's up front being adj. are great, as you can set for street, tow or off road. I typically stiffen up the front 5 clicks over my road setting. For everyday the Fox are awesome - they are firmer than the stock Rancho's but more compliant, composed and controlled. You can go one click off full soft and have great street ride, stiffen up a bit off road and have a great package off road as well. 10x more capable than stock off road. Overall I am very happy with the set up and I tow a bunch - typically 7k - 9k total load. I have found that Fox offers the most compliant shock, with King stiffer and Icon stiffer still. Here is a link to video on air bags vs load level hitch Link air bag vs load level hitch https://www.facebook.com/fastwaytrailer/videos/396362497739001/

I have 2020 AT4 with BDS 2.5" lift (so 4.5" over stock). I have 2.5" Fox adj coilovers - Fox 2.0's in the back - stock UCA's. I don't have big tires. I did run into issues as I already had method NV 18 x9 - 18mm offset - I had to use 1.5" lug extensions to clear the tie rod. 20" wheels are "more flexible" as the tie rod will go "inside" the wheel barrell on the larger wheel. Their is a ton or "inboard" room for tire, if you clear the tie rod. You have more wheel well room, than my GMC - but that will be the issue on larger tires - some trimming is likely with 37's. I plan to get new wheels with -12mm offset and go with 33's or 34's if I can fit them. You can save a few dollars going zone over BDS - pretty much the same stuff, and if not going offroad a lot, it is all you need. I would say if you can upgrade to 2.5" Fox adj coilovers, they are very nice and you can dial in the ride you like. I have street, tow and off road settings I use. Super happy with the set up. Here are photos of mine and the various clearance areas FYI Note nice straight axel - no angles for CV's like level kits. Lots of inboard tire room 2 fingers up front when straight with 275/65/18 duratracs A bit more clearance at the rear Rubs in reverse at 2/3rds locks with stock 275/65/18's Not a ton of extra room No rub but no extra room at full lock

Agree - That was the other bonus on my trade - the 2020 is $36 a month cheaper than the 2019 and residual was 2 points higher (63% vs 61%). $68k truck for $719 a month including tax (7.75%) tax rate - Was considering another Raptor (had 2014 and loved it), but was not really an eco boost fan - once I saw the lease vs buy numbers the AT4 was a no brainer! Added BDS 2.5" lift kit with Fox 2.5" adj. coilover shocks and Fox 2.0's in the rear - great truck, with great suspension with a V8 - very happy with the total package!

I keep ratchet straps, mechanics gloves, zip ties and my key bag (storage, trailers, toys etc.) in the rear seat back storage compartment on the drivers side. In the passenger side I have manual tie downs for moto's, mechanics gloves and some room. Under the rear seat I have OEM jack, tow strap, trailer hitch receiver with u clamp for tow strap, u clamp for tow strap, pancho, shovel, 24" breaker bar, socket and extension to fit lugs, trailer hitch receiver, blanket, store bags, jumper cables, micro fiber towels, Nitrogen bottle regulator and wrench for securing it on bottle (which is in bed). Most of the time in front of rear under seat storage I have 3/8" and 1/2" torque wrenches in their own cases, a soft side tool box and a soft side bag with 20amp cordless drill and 20 amp impact gun. In the passenger door behind driver I have a battery Norco battery jump starter (or can be used to charge phones or computers etc.) . Other that that is all clear back there - well except for the front windshield sun shade - LOL After looking to see what I had I am like, do I really need all this stuff in here? But then its storage right and if you need it, best if its stored where you are going use it!

I have a 2020 AT4 Carbon Pro - 6.2l 10speed - I tow a 24' enclosed car trailer - 7k-9k lbs is typical. Truck, motor and tranny combination are great. I needed to add load distribution hitch, sway control and would recommend upgrading from duratrac load range C to a BFG K02 in load range D or E if towing a lot. When you get in the wind, there will be some sway, more in the Trail Boss/AT4 due to the added height and softer rear springs. I tow in S.Cal - so we go up and down a lot here - so towing milelage is 8.4 mpg combined +/- going hard. On flat ground maybe 9-10 mpg. With the small fuel tank, not much towing range. For towing 6 times per year, if its working I would probably just keep what you have - but you never know what kind of deal you would get, but with patience and diligence you can find them. I had a 2019 AT4 Carbon Pro with 10k on it, wanted to get tow mirrors and rear cameras for better towing visibility- was trying to figure out how to swap mirrors - ending up finding a deal where I traded for a 2020, got tow mirrors and it only cost me $600 - went from 10k miles to new. Took a number of months to get that deal and lots of dicussion via email - but found the deal and glad I got tow mirrors. When you get to the point of towing across the country you can't beat the modern diesel 2500 or 3500 with 10 speed (or Ford 250/350) they make short work of towing and get better mileage. Plus the added weight of the HD diesel trucks increases your safety when towing. At some point when thing go wrong, you don't want the tail wagging the dog, so bigger is better for your tow vehicle!

I have 15,000 miles of driving on 6.2: 10 speeds in AT4 - 2019 (10k), 2020 (5k) of which 12k miles is towing 8k-9k lbs. Went from 2019 to 2020 to get tow mirrors. Both trucks shifted like butter and worked perfect. 10 speed really shines for towing over 6 speed. I would not buy 8 speed when you can get the 10 speed that offers more range and overall is a smoother shifting tranny!

My buddy removed the 2" rear blocks on his 2020 AT4 to level - ended up adding back 1" blocks a few days later, but has had no issues since (8 months of driving and counting).

Bottom line on the numbers is they are selling a ton on new trucks! I love my 2020 AT4 and loved my 2014 6.2L Raptor before that. No problems with AT4 - Raptor went 100,000 miles, 2 sets of tires, 1 set of brake pads and a bunch of oil changes - that truck was bullet proof! Like to have a V8 or big diesel - so my next truck if half ton will be GM and if diesel will be GM or Ford. Ram just doesn't do it for me, sans the TRX - now that I would buy if I could get one at MSRP! Toyota would get my money if they step up with a modern truck, motor (V8) and tranny and all the luxury and amenities of the top 3 before I would consider them. We had 3 Sequoia's (first two with TRD superchargers) and all three went 125,000 miles with virtually zero issues. We are living in a time of great products and we have lots of good choices - I have gone to leasing, so new truck every three years from now on - can't wait to see what I can get in 2023!

No question the truck looks better without the tow mirrors - the standard look better. If you don't tow that would be the way to go. I agree as stated above the tow mirrors do provide blind spots when looking forward. If you tow the tow mirrors offer a significant advantage over the standard mirrors. I traded my 2019 AT4 Carbon Pro with standard mirrors for a 2020 AT4 Carbon Pro with tow mirrors because I tow and the standard mirrors do not allow any visibility down the side of a 24' enclosed trailer. The Tow mirrors offer great rear visibility when towing and the cameras in the mirrors also offer another level of visibility when towing, that make towing much safer with the tow mirrors. If you tow get them, if you don't or tow small open trailer don't!

Not a Trail Boss - but here is what they look like on AT4 - when it comes to towing they are a night and day improvement over stock mirrors.

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Front shock are remote resi - rears are not - they don't offer one (yet) - Fox told me they have a rear 2.5 piggyback (which would be ideal for easy placement) that is similar in length needed, but not valved for the truck, so was not sure how it would work and may need to be re-valved. I was not willing to go through the trial and error. Not sure about your second comment - there is a lot more "inboard" room that stock with BDS lift - my only issue for 18's was the tie rod needs clearnace - so you need at least 0 offest wheel to fit, or spacers or lug extensions for anything with positive offset. Here is a photo of inboard spacing.

2020 AT4 Carbon Pro - BDS 2.5" lift with 2.5 Fox Adj. coilovers in the front and 2.0 Fox in rear, lift also comes with new block for reat 1/2" taller than stock. Wheel are 18x9 - 18mm offset Method NV wheels with stock 275/65/18 Duratracs. Had wheels from 2019 AT4 Carbon Pro - they would not fit with BDS lift, as they hit tie rod - so had to go with 1.5" wheel lug extensions to make them work. Plan to go to same wheel in -12mm offset to move wheel out to clear tie rod and to allow for larger tire. If I had 20", would have been ok, as the tie rod will go inside the barrel of the wheel on 20" wheels - so more clearance with 20's. I prefer 18" for more tire side wall for off road, so will have to go with 0 offset wheel or negative offset to make 18" work. Stock 275/65/18 - still hit in reverse at 2/3rds lock on front corner. Photos below to show clearances. BDS LIft Front Front clearance - wheels straight Tire clearnace Front 2/3rd turn Tire clearance front full lock Tire clearance front - rear of wheel well - turned straight

I loved my 2019 AT4 Carbon Pro 6.2L/10spd - did everything well. But I was towing a lot and the standard mirrors were lacking and even though I got the tech package and all the cameras, I did not have the see through camera set up for a trailer. So I was looking to move back to a 2500 or 3500 HD diesel. I went for test drive and knew it would be better when towing, but was not the truck I wanted to drive the rest of the time so I ended up finding a 2020 AT4 Carbon Pro 6.2L/10spd with trailer tow mirrors and the additional tech package all the trailer tow camera views. Gave me all the views I needed for my 24' enclosed trailer and tows like a dream. Made a few updates with 2.5" lift (4.5" overall) from BDS with Fox adj. coil overs and a Deaver custom rear spring 10 pack to better handle trailer tongue weight. The only thing I wish I could change is the size of the fuel tank - if I could get 50 gallons that would be awesome - when towing the 26 gallon tank is just too small. So I guess I could say I loved my truck so much I bought it again! These really are amazing trucks that do everything well!

Mine is still on stock 275/65/18 Duratracs - will go to 285 or 295 when these are done. Here is photo of my 2019 with RS SST level kit without their rear block and stock wheels - then with their rear block (about 1/2" taller than stock), with Method wheels for reference.

Here is my 2020 AT4 with BDS 2.5" coilover lift kit. I would recommend you consider a lift kit (even if you don't go to the expense of new shocks) over a leveling kit to get proper geometry on your cv axels. If you start at 2" with OEM AT4/Trail Boss lift - then ad 2-3.5" - you end up with pretty extreme angles and wear an tear will occur. You can spend and extra $500 - $700 up front for proper lift and get good CV angles, or pay the piper down the road. I had a 2019 AT4 with Ready Lift SST 2" level kit - picture below of CV axel angle - it i not ideal - RL states on site that they do not recommend using "auto 4WD" with level kit due to torque on the front diff from poor axel angels when shifting on the fly at speed. Rough Country, Zone and BDS all offer proper lift kits that lower the front diff to proper geometry angles in the $1,000 - $1,500 range. Level kits are $400 - $700 - so you get to decide. If not dong much off road or using 4WD much - then level will likely be fine, but if off roading or using auto 4WD - buyer beware 2020 AT4 with BDS 2.5" lift with Coilovers 2020 AT4 with 2.5" BDS lift CV Axel - pretty much dead level 2019 AT4 with Ready Lift SST Kit 2" level kit - pretty extreve CV Angels - RL states - "do not use with auto 4WD"

Spacers are not ideal - but in my case I already had the 18mm offset wheels - when I ordered the lift the shop thought it would fit - but it did not clear the tie rod - so spacers added to make it work. BDS told you 0 offset, which is minimum you need to clear tie rod with 18's - anything that has negative offset (e.g. -12mm NV 305's) will give you "more" clearance on the inside and will exceed the 5.5" they told you about - they do push your tires outside your fenders a bit - No way you get 18 x 35 x 12.5's on with 2.5" lift without major surgery to your wheel wells to create the clearance. At 2/3rd lock my 275/65/18 just rub on front edge of fender over any bump. With 0 offset or -12 offset wheel that will improve - but won't go away - so any tire larger, will require some trimming. Here are some photos with stock duratrac's (275/65/18) to give you and idea on clearance.

Sounds like a great set up and 0 offset should be ideal! Question - I have NV 305's - in 18" I thought they only came in 18mm or -12mm - I have the 18mm, with spacers (they otherwise would not fit) - the -12mm would be the way to go with the 305. I found with my front shocks, when delivered from the shop they were set at 8 clicks (0 full soft - 12 full stiff) - I have played with them quite a bit and for "road" use I go with 2 clicks (from full soft) and that is good ride quality, but still more composed than the Rancho. For off road I am at 6-8 clicks and for towing I am at 5 clicks. I think the system would benefit from having an adjustable piggy back 2.5 for the rear. I talked to Fox and they gave me an option that is same shock length as the 2.0, but it is not dialed in for the truck, just an off the shelf valving. They told me the 2.0 on the back had quite a bit of valving refinement for BDS, so for now I am not switching. BDS says they plan to add a rear 2.5 option soon (but that was 8 months ago). My guess is demand would be limited, as the cost of the shocks at $1,350 for the pair, would increase cost of lift by another $1,000.

Yes they do - same sizes - often offered in a number of different offsets. For the BDS lift - with 18" wheel you will need to have an offset of 0 to negative - to clear the new tie rod - with 20" wheels, the tie rod will go "inside" the barrel of the wheel, so some positive offsets will work I put the 2.5" BDS lift with coilovers on my 2020 AT4 (so 4.5" over a stock truck and 2.5" over stock AT4). I have 18x9 with 18MM offset Method NV wheels, from my 2019 AT4 - had to use spacers to clear the tie rod - plan to change the wheels when I get larger tires to a -12mm offset so no spacers are required. Once you go past 0 on offset you start pushing the wheels outside the fender line - as noted by prior poster. Find a shop in your area that installs BDS kits regularly and they will be able to help you get what you need and get the right wheels with the right offset. You will find the BDS 2.5" or 4" with Fox coilover shocks is a great system - spend the extra $300 to get the adjustable shocks - it give you a lot more flexibility in adjusting the ride to what you like. Ride quality is improved, cv axel angle is dead level and overall offroad performance is significantly enhance over stock.

I did this morning when I dropped the truck off - this particular GMC dealership Mgr. in South Orange County CA told me they had not had a single case yet they had addressed, and was unaware of the issue. So for now I will just enjoy my track and keep my fingers crossed!