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  1. The short answer to the OP's question is that any "level" kit for AT4/Trail boss may impact use of auto 4WD. CV angles with level are to extreme in the front, no matter the level kit mfg. the issue is when the truck moves into 4wd under some conditions the front diff suffers extreme torque and it can be severely damaged. RL added a note to the SST kit after a few months, due to customer complaints of loud noises and a few customers who complained they lost their front diff's when using 4WD auto. When you speak with knowlegable shops they all seem to agree that 4" of lift is the point of no return - so 2" added to AT4 + 2" more. Unfortunately the RL level kit, noted above has no mention of the "auto 4WD" function impact, but their SST kit they have the following note "NOTE: Use of Auto 4 HI feature not recommended", the only difference is the rear block. It is 1.75" level - so 3.75" overall, where SST states it is a 2" level (so 4" overall). The upper control arms correct the angles for the upper ball joints, but do nothing for the CV axel angles. I had a 2019 AT4 Carbon Pro - I installed the RL SST kit - CV angles were not good - no auto 4WD. I traded in for a 2020 AT4 Carbon Pro with trailer tow mirros, as I tow a lot and I did not want any issues up front. Pictures below. For the 2020 I went with BDS 2.5" lift - which provides proper CV angles (better than AT4 from Factory). I have the full program with Fox 2.5 DSC coilover shocks - so a $4,700 deal installed. I love it, but it is a lot of money if you don't go offroad much and just want a level. If you want to use Auto 4WD, you will need a lift kit that lowers your front diff, to keep CV angles within OEM spec. You can buy BDS or Zone 4" lift kit without the Fox shocks and save some $ - but you are still looking at $2,086 for BDS and $1,300 for zone (which is made by BDS). But that is 6" over stock -so 4" over your AT4 OEM ride height - currently they do not offer the 2.5" lift kit without the fox coliovers (which is 4.5" vs stock 4" for AT4). There are other mfg. of proper lift kits as well that can get you same outcome, as long as they have a diff lowering brackets in their lift kit. Zone is the best overall value, for just the lift. RL SST: https://www.readylift.com/at4-trail-boss-plus-2-0-sst-lift-kit-gm-1500-at4-trail-boss-4wd-2019.html BDS: https://bds-suspension.com/product?kid=749H Zone: https://zoneoffroad.com/products/4-in-ifs-suspension-lift-kit-2019-2020-chevy-trail-boss-gmc-at4?variant=33403092729944 Below are photos of my 2019 with RL SST kit and my 2020 with BDS 2.5" kit - you will note the CV angles are level on the BDS and are quite extreme on the RL (note boots). There are no short cuts for AT4/Trailboss to do a proper level or lift. Only other options other have tried is a shorter block in the rear for the level. That is the cheapest option, but may not work the best. 2019 AT4 - Ready Lift SST Kit - CV Angels - level ground 2020 AT4 BDS 2.5" Lift Kit CV angles - level ground 2019 AT4 Stock 2019 SST RL Level - dead level 2020 AT4 BDS 2.5" Lift - Fox shocks - a little rake
  2. Hi, OEM 18" AT4 Wheels I have four (4) OEM GMC AT4 OEM wheels for sale - no tires - taken off the truck at 50 miles +/- - new condition. $1,250 for all four - only selling as complete set - local sale only (Southern California) Suspension: I have OEM knuckles, front Rancho shocks and springs, rear Rancho shocks and lift blocks and skid plates off 2020 AT4 (replaced with BDS lift). Taken off truck at 1,582 miles. $550 - sell as a package only - local sale only (Southern California). - see link to ad on Craigslist, it has lots of photos Link to Craigslist ad for shocks: https://orangecounty.craigslist.org/pts/d/san-juan-capistrano-2020-gmc-sierra-at4/7216378026.html $225 - Chrome Exhaust tips - off 2019 GMC AT4 (swapped out for the black ones). I traded the 2019 in for a 2020 with trailer mirrors (why I have parts for two different years). Can ship these, buyer pays shipping. Reasonable offers considered. Entire bundles for $1,500. email me at [email protected] and I will respond.
  3. Here is a dyno for 6.2L from Whipple website - 160 ft. lbs. +/- and 120 hp +/- 5.3L - 167 ft lbs. +/- and 121 hp +/- link: https://whipplesuperchargers.com/index.php?dispatch=products.view&product_id=522
  4. Stock 18" OEM wheels have 26MM offset- which is about 5.50" back spacing on a 9" wheel - you need 4.5" backspacing on wheels to clear the tie rod. That is about <12> MM - I had Method 18x9 with 18mm offset (5.25" of back spacing) and we thought it would work - it did not clear tie rod - had to add 1.25" of spacer and wheel lug extensions to make it work and it just clears. Not ideal, but works for now - plan to either get 20" or <12> mm 18 inch soon so I can clear without spacers and lug extensions and add larger tires. With 20" wheel you don't have same issue as the tie rod will clear - albeit it is inside the wheel radius.
  5. Know how you feel - at 10k my 2019 was also flawless - and it was all done! Hated to give it up. But when I found the exact same truck (sans the painted wheel arch flares) with all options I wanted + tow mirrors I figured it was worth reaching out to dealer. Mine was leased so I emailed dealer you take my lease back, and I will lease the new one, drive offs only. GM called me, said ran my lease, payoff was $52.9k, they would take it and lease new one to me for drive offs of $1,280 and $731 a month payment including tax. My 2019 was $750 per month. The $1,280 included the 1st months payment of $731 - so drive offs were $559. I said ok - they delivered the truck to my house that night and took mine away. What I gave up on 19 was Ready Lift SST 2" level kit - which cost $915 installed - but I was not happy with the CV angles or the fact you can't use auto 4WD with that level kit (did find out till after) - so it was cost I did not mind giving up. New truck got 2.5" BDS lift - better all around (cost a lot more, but worth the $$). So now I feel like I have the best of all worlds! If you get the right deal - you will not regret the tow tech or the big mirrors! The updated visibility is awesome.
  6. Hope that works out for you, that would be a great! No dealer near me seemed to have a clue on how to approach this or want to touch it. Great addition for towing!
  7. Do a search on this topic there are a few very extensive threads on this topic - including a step by step wire hook up and what you can get to work and what you can't. I talked to multiple S. Cal dealers about doing the switch - most said it could not be done. It can be done, but you won't get all the features you would it ordered from Factory. Only dealer who would actually quote me the swap wanted $2,000 for a $290 factory option and then when coupled with advanced tow in the tech package you get all the towing camera features, which is a great feature for towing. I ended up trading in my 2019 AT4 for a 2020 AT4 with tow mirrors and advanced tow. I got all the factory features and it only cost me about $600 to do the truck swap, so overall a great option, as I went from a 10k mile truck to a new truck with all the features I wanted. Good luck with getting this done, it is well worth doing as the visibility around an enclosed trailer is so much better, add the cameras down the side of the truck and trailer, along with the see through accessory camera and you have a very good and safe towing package. 2019 without 2020 With Tow Mirrors Tow Mirrors
  8. Post pic's when you get it - looking forward to seeing it with 35 x 12.5's!
  9. I had a shop recommend the sumo springs as a "next" step, after E rated tires - I think with WDH and sway control I have what I need for loads I am hauling - up to 9,700 lbs with trailer and 2015 Z/28 inside. D or E rated tires will be in my future as I replace the stock C rated goodyear duratrac's on my AT4 with something larger. I would take it step by step - do one thing - see how it is - add the next piece then see how it is. At some point if you have to keep adding you may have the wrong truck! The 1500 series should be good to go for up to 10k with 1k in tongue weight. For me if I were towing 9k plus all the time i would move up to 2500 diesel truck again, but for the loads I tow (4,500 - 9,700) the 1500 is fine and it offers a little nicer everyday driver when not towing than the 2500 - not to mention it is $20k less expensive!
  10. I looked at Method Con6m us that what you have on order - or is it a Icon suspension with Methods? If you ordered the Con6 it does not look like you can order the -12 mm offset (4.5" of backspacing) 18 x 9's - only the 18 mm (5.5" backspacing). If you consider other Method options the -12mm with 4.5" of backspacing will give you more inboard clearance and better overall flexibility to fit larger tires. FYI stock AT4 18's are 26mm offset - so 18mm does pick up some inboard room - but the -12mm picks up a lot more. I had the 18mm with 5.5" of back spacing - with Ready Lift 2" SST kit with UCA's on my 2019 - I had less than 5/8" of clearance to my 275/65/18 - I could not have fit a 295 - a 285 would have been very close. With stock upper control arms you pick up about 1/4", so a 295 likely would just fit. I am using same wheels on my 2020 - when I added BDS 2.5" lift kit - the tie rod hit the wheel, so I had to add 1.25" spacer and lug extensions to make it work. Backing up at full lock I have some minor rubbing I have not sorted yet. So I am now going to swap to the -12 mm with 4.5" of backspacing so I can have more tire options and clear the tie rod without the spacer or lug extensions. I have Method NV's. Good luck with you updates - should look good. 2019 with 18mm offset Method NV 18x9 - inboard clearnce stock Goodyear Duratrac - 275/65/18
  11. I have 2020 AT4 (had 2019 AT4 before) and tow a 24'' Intech enclosed trailer. No questions this truck is sensitive to tongue weight - I have found different settings on WDH for loaded or empty will change how it behaves. Too much tongue weight and it will give you a little sway. In addition to WDH I run a sway control bar on trailer that attaches to truck hitch as well. Have had good success with this set up on past trailers and with this one as well. My trailer will drop @$$ end 2.5" without WDH and about 1" when it is set with some tension. I have bars rated at 1,500 lbs each (this is important, as if you have 800 lb bars, that is all the weight you can shift to front wheels). To get serious tension aon WD bars a good trick is to hook up, then use jack to lift the back of the truck up above level - this will allow you to catch lower chain links and add to tension and throw more weight forward. I also find that this truck sucks into passing vehicles, but mostly big trucks or motorhomes - not much on cars. I do think it is something you get used to and notice less as you tow more. I also have the advanced trailering package and tow mirrors on my 2020 (why I switched from 2019) and find the overall package is awesome. The mirrors and camera views down the side and out back make trailering so much safer and easier. I knew it would be a plus, but had no idea how much better it would be. I added a photo of the sway control set up I have (not same brand, but same set up).
  12. No Max tow option for AT4's - so all have 3.23's
  13. 10-11mpg towing a 5,000 box through the wind is pretty good. I have 2020 AT4 and had 2019 AT4 before, both with 6.2L - towing my 24' Intech empty I am at 4,600 lbs +/- - at 60 - 70 I get 9-10 mpg. at 8,000 lbs I get 8.4 - 9.2 pending the number of hills. So you are a little better, but not as much as you might have hoped. Regardless a very nice set up! Can't believe you got 30 mpg - I have never seen anything north of 21 in mine. For comparison my 2019 over 10,500 miles averaged 14.5 mpg of mixed city and freeway driving, with about 2,500 miles of towing thrown in as well. Best tank was 21 and worst at 8.1 towing into the wind.
  14. Specs for my tire are 32.3" tall - A BFG K02 35 x 12.5 x 20 - 34.5" tall so if all else is equal - you would be 2.2" taller than mine - so 80.25 + 2.2 = 82.45" +/- tall - when comparing to mine as is. So closer to 4" of total height increase over where you are now (82.45 - 78.5)
  15. James Here is photo on level ground - no trailer - there is some rake. Other Information Height - ground to top of shark fin on roof is 80.25" +/- and 88" to top of antenna with 275/65/18 tires - 2.5" BDS lift on top of 2" factory lift on AT4 - so figure you need 81" minimum to clear your gargage door or header
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