GMC SIERRA AT4 - Problems, Issues, Mods, Upgrades and Some Fixes I've Done So Far

[@colbyhal]

I bought a 23 sierra at4x in march. Ran 91 octane, changed oil every 5000 km. ( I live in Estevan sask.) and at 11000 km my motor went. Bearing in the crank went. Currently still waiting for a motor to come in! It’s also the 6.2l

[@Donslife]

That’s tough

[@jonsmith3664]

6.2 are trash. That's why the lots are full of them. Used and new.

[@colbyhal]

@@jonsmith3664 I’ll be trading it off when warranty is up. Definitely don’t trust it that’s for sure! Back to the raptor I go

[@Future-Focus]

@@jonsmith3664 lots are full of them? theres 15 of them in a 100 miles of me what are u saying

[@NST320]

I read somewhere that the 5.3 and the 6.2 have the same compression ratio. The way I understand it, with the higher octane gas. The chance of pre ignition (spark knocking) is less. The lower the octane, the chance of pre ignition increase. Thank you for all the content you put out. GM needs to hire you as an consultant. You have done so much with aftermarket parts. Can’t wait to see what’s in store for the corvette.

[@jonsmith3664]

I read that too however, the ECU adapts to compensate so not an issue in todays engines. Premium fuel is a marketing gimmick. The 6.2 is a "will this thing cost me 5000k today" engine. Avoid it.

[@Return2Nothingness]

My grandad was a firm believer in changing oil every 3,000 miles. The reality is that every vehicle he owned saw well over 180 or 200k miles...so I plan to do the same!

[@danielsweeney-me7wm]

Great video! The GMC Sierra is what brought me to your page so I am happy to see videos like this.

[@Donslife]

Awesome! Thank you!

[@dolsavsky]

Im looking at some used AT4's. I hope the previous owners cared for their trucks like you.

[@Donslife]

I’m sure there are some great ones out there

[@DougT25427]

Great video I have the Duramax in my 2023 AT4. I have a lot of experience with the Duramax as I have owned and put a lot of miles on a 6.6 version. My biggest complaint of the baby Duramax is it is way too quiet. I really like the throaty sound of your 6.2. Not enough warnings or cautions can be given about the electrical systems of these trucks. It isn’t something that just happened with the newer trucks. My 2007 is finicky about its electrical system too. It’s just become worse in the newer trucks. I installed a Mean Green brand alternator on my 2007 just to keep the chassis voltage on the upper end of 13.5 volts. The sensors like the upper end of the voltage limit and you won’t find that written about anywhere. Many of my quirky electrical problems went away once those sensors were happy with their voltage. The new trucks rely even heavier on the BUS system and use a few operating voltages not just 12vdc. The BUS system now is the Big Brother in all of these trucks. One just can start cutting and splicing into harnesses. If they do they will be come intimate friends with the local GM service shop… 🤣🤣🤣🤣 If GM really wanted to support the DIY/Mod influences of their owners… they really don’t want to… they could add a few circuits in one of the fuse panels for us. I’d like to see a 12vdc key on circuit and a 12vdc constant on circuit that is unmonitored by the BUS system. I can dream of some other unmonitored circuits I’d like to have too. I’m not looking forward to the day you strip the Khaki Green wrap off of the truck. I’ve said it many times it is the best color I’ve seen on a AT4. I didn’t know how long a wrap would last until you mentioned 3 years. It's one of my too far of a reach dreams to have my AT4 painted in that color.

[@Todd-tz9qq]

I enjoy your videos. Very straight forward with no unnecessary babbling.

[@adamg1408]

I've had folding bed covers before and learned to hate them. The soft, rollup, covers are also 'meh' for me. Being in New England where we get snow (along with all other kinds of weather) means the cover needs to hold up very well. Heavy snow will stretch out soft covers. Folding, or hinged, covers are OK for heavy snow, but (as mentioned in this video) suck for how you lose access into the bed. I never flipped the folding cover so that it was against the back of the cab (no way to secure it from what I recall). So 1/3 of the bed wasn't readily accessible. I'm now using a Retrax Pro cover (manual) and love it. No wires were needed and it's easy to lock when I want. Also, since it's not powered, I can leave it unlocked and get into it without having my keys on me. They do offer a version with rails for other things, like mentioned for the EGR. Never really looked at that version since I don't have a need for such things. I will mention that it appears that the 2022+ (refresh) Sierra trucks have a different passenger side fuse box configuration. At least in my Denali it does. Any fuses that show 'not used' in the sticker are not usable at all. It sucks because I wanted to use a hardwire kit for my dash cam setup and but that turned into a dumpster fire. I now have a Gen5DIY wire harness coming (out for delivery today) that I'll use to power the dash cam setup when I'm in the truck (or it is on). I'm planning to get the Borla exhaust on my truck once it's off lease. Or when I have access to a place where installing it won't be a PITA. Right now, my driveway is suboptimal for that (not flat enough to do the install). Keep up the solid content Don.

[@walkerjlc]

Don thank you for all these AT4 videos. Really helps and makes me want to do some things on my own 2022 AT4

[@Donslife]

You’re welcome sir

[@DJ_Williams]

Always be different….a white and black truck is mostly common. Me, I’d rethink the green..that look is sharp

[@edhcb9359]

Kinda crazy that such a “tough” truck needs to be have such detailed care and handling instructions so it doesn’t implode! 😂

[@joshraines]

Glad to hear all the positives. When I picked up my AT4X, my dealership said regular gas is fine, you just won't get all the available horsepower and to fill up with premium every so often; I thought that was interesting. Also glad to hear about no drone with your exhaust. I did the muffler delete for about a week and had to put my stock muffler back because the drone was so bad. I have the S-Type on order...should be here in a few days!

[@DKLabs99]

They told me the same

[@bouncer58]

Thanks so much for your awesome videos. Your research and detailed explanations have been so helpful to me. My wife is not as happy as you cost me $$$. I have a '22 refresh AT4 with the 3.0. I've had several 6.0 and 6.2 engines in GM vehicles and love them but opted for the 3.0 for fuel economy. It doesn't disappoint but jealous I can't make performance mods like the 6.2 guys. Your videos convinced me to look at Stands lighting and purchased the QB cubes (on Putco brackets), raptor markers, and a Nuuk 20"). I love them and feel they are a great value for the money. Also have the Auxbeam controller. Also did the Bilstein 5100's all around. Was really happy to hear you are looking at a sport bar. I want one badly but need one to work well with a bed cover. I currently have the BakFlip MX4 which is great but understand it will need to go with a sportbar. I'd love to have something like the GoRhino 2.0 with retractable lightbar. I don't use parking garages much but noticed a tight fit and I think lights on a sportsbar won't make it. Good to hear about the spacers holding up and not causing premature wear. I think that will be one of my next mods. Thanks again.

[@Donslife]

Thank you for dropping the comment and supporting the channel. I can't wait to have a sport bar that can work with this cover

[@RobustArid379]

Thats a nice looking truck, dam shame you are having trouble with everything

[@Donslife]

Not too much trouble. Little hassles is all

[@estebanalvarez2235]

When you get your C8 you should do it the same color of the truck so they can be triplets for a little bit, until next year the wrap should be removed.

[@Donslife]

Triplets 😂

[@michaelpanacheese604]

Great review. The truck looks great. Keep the 📹 coming sir

[@Donslife]

Thanks. Filming videos like this is something I enjoy doing too

[@BG-vq9fd]

Apparently I missed some of your videos. If I keep my 2020 AT4 it probably needs that great sounding exhaust. I am wanting a 2024 HD AT4x gasser. I also need to try that L9 thing.

[@zeebeefpv2273]

So what is the tap method or product for wiring aux lights (for headache rack)? You are correct: tapping into the 7pin isn't fun to deal with the computer issues...

[@johnlundvall8911]

The thing that surprises me the most is your fuel, the lowest octane we have in Sweden is 95 and premium fuel is 98 or even 99.

[@jasonmurley301]

Its a different way of measuring it.

[@johnlundvall8911]

@@jasonmurley301 How do you mean, that octane is measured different in the U.S then Europe? In the other hand nowdays we have what is called a reduction law so i think about 10% or more is biofuel mixed in the gasoline and diesel.

[@ChaddDaugherty]

Thanks for the videos -- I've been subscribed to your KZbin since puchasing my GMC Sierra Elevation 5.3 X31 in July, 2023. Question Re: L9: I've been driving almost entirely in L9 to disable DFM and auto stop since owning the vehicle (based on your past videos and recommendations). Is it safe for the transmission to run in L9 at highway speeds, such as 60 - 75 mph ? So far, I've been putting it Drive at those speeds... Let me know your thoughts -- thank you

[@ChaddDaugherty]

Also FYI Sierra is a 2020, 68K miles at present, 56K at purchase

[@Donslife]

I am sure it is safe but I do the same thing at 60+ mph and use Drive. I do that to keep the RPMs lower and save a little fuel

[@dwkentinc]

NICE OVERVIEW, THANKS

[@Donslife]

Thanks for watching!

[@carloskhalil2428]

my 2020 gmc sierra slt 6.2 only missfire once, since i install the pulsar LT no missfire and doesn't consume more oil .

[@Donslife]

I'm glad I haven't had the oil consumption issues like some have

[@Synwright]

🎉❤👏👏👏👏👏 I love these videos, ❤ collage of past videos and info. 😊✌️out.

[@Donslife]

I am glad you like them! Thanks for the support!

[@Lloydski]

Hey what are you running for wheels/offsets and tire/sizes in this vid looked all over the mods you have done down below but didn't see it anywhere. Love those black wheels. Knock on wood my 6.2 is still doing great they sold millions of them and not all are bad just luck of draw I guess. ALL trucks have some kind of issues.

[@Jeremy-od7fh]

Love the new look. Awesome job. Quick question what would it look like if you could add a black piece of wrap on the front edge corner of bumper to continue the look of the black fender flare down to bottom of the bumper. Just an idea and since your handy

[@carlcolorado3549]

I see you have 1 catch can. If you look on your engine on the passenger side valve cover you see a hose going from the valve cover right into the in take. You're still getting vapor into your intake box. Thought I'd point that out.

[@Donslife]

The passenger side on is pulling filtered air in from the air intake elbow in front of the throttle body. The driver’s side one is expelling vapours to be burnt off in the intake manifold behind the throttle body. We’re good with one on this engine.

[@patrickflosse8807]

Bought a 2024 Raptor this Spring. Impulse buy. Its a great truck but I don't like the fact I cant lift it and always have to go through the different exhaust sounds after starting it to get the rumble sound I love. That's my bad for not looking into first... At a $110K I want what I want. This brought me to the Sierra 1500 AT4X AEV. Im able to do well on a trade right now but seems to be a lot to worry about with this 6.2L ??

[@Donslife]

Frequent and high quality oil changes seem to be the preferred maintenance. I do mine every 3000 miles. I drive it in all conditions too. I’d buy another 6.2. Of course I would prefer not to have DFM and questionable lifter components

[@josevillar1912]

I Like you Wrap Color.

[@Donslife]

Thank you

[@aaronknez1906]

Any comments about your 10 speed transmission? Any shifting issues? Is it clunky.... super smooth? My 21 AT4 is good most days then it'll be kind of rough and a little "catchy" then eventually figure itself out. Love your videos! Keep it up!

[@Donslife]

Thanks for following the videos. My transmission has been fine most of the time. No real mechanical concerns but depending on conditions it can randomly shift a little hard, pretty much always in low gears. Like you said though, it seems to figure itself out too.

[@curtisjoyce8002]

Hey Don, just wondering if you could give us an update on how are enjoying your new Toyo’s this winter. Sorry if you have done this somewhere already.

[@Donslife]

I have been very happy with them. I knew they would be great in decent weather. It turns out they are great in the ice and snow too. I would buy them again in a heartbeat.

[@claytontycksen9472]

Don - love your videos. I have a 2021 Sierra 3500 AT4. It has a 6’10” bed. What length bed is your AT4? It would seem that EGR doesnt make the rolltrac for the 6’10” Sierra beds.

[@Donslife]

They don’t yet. Thank you for watching the channel!

[@maull2020]

Hi Don, does your truck have an 8 speed or 10 speed transmission? I have a 2022 GMC Sierra 1500 refresh with the 3.0 duramax, with about 14,000 miles. My truck came with the 10 speed and I really love the truck. I ask about the transmission because I’m now having issues with my transmission, but I haven’t been able to find any videos online. I’m wondering if this is good or bad? I love what you’ve done with your truck by the way. The lights on the running boards is a nice touch.

[@Donslife]

I have the 10 speed transmission with my 6.2L. Other than half a dozen hard shifts in the lower gear range, I haven’t had much weird behaviour. The truck is almost 3 years old now. Thanks for watching my videos!

[@maull2020]

Thanks for the response! I appreciate it and your videos.

[@adamthompson8432]

OMG I’m in shock? You have to put a battery charger on the battery??? That’s crazy!!

[@Donslife]

Correction, a CTEK AGM smart charger. It makes a difference for battery maintenance

[@Donslife]

linktr.ee/donslife - Links to all of my products and discounts

[@juasmith1]

So that's what all the click clacks are behind the dash when I turn off my '24 Trail Boss.

[@jonsmith3664]

Nice video!!!! The color is awesome, however, the purpose of that particular color is to have it in mat. All of it incl. the trim. Shiny doesn't work here. Is that 2 tone?! egad!!! Why buy the 6.2? It's known for major issues. Unless of course you have a $8000 reserve fund to fix it when it goes bad. The offset will wear out your bearings prematurely. Not up for debate. It's simple leverage mechanisms at work. That light bar has to be covered at all times in most provinces incl. Sask. unless you're....offroad. I've been pulled over twice. I've never seen an aftermarket exhaust not drone. Ever. And I've had a few. My friend has that exact exhaust and you may as well forget having a conversation with the driver if you're in the back seat. His neighbors also told him that his exhaust is annoying at 5 in the morning. Those square exhaust tips from GM look very Canadian Tire ish. The ones you have are a tad better but still tacky imo. The freedom blade also looks very CTish imo. I've had 3 flip tonneaus. They're a pain and heavy. But that track one is absolutely useless in Canada. Anything aftermarket will eventually hinder performance and will likely void your warranty. It's the cost of going that route. Nad yes...lots of gremlins in these trucks electrical system. What's a sport bar? Is that the new fad where people dress up their city cruisers to look like an overland cruiser? Whats the purpose? I don't get it. Overall a very nice truck.

[@Donslife]

Thanks for watching and have a wonderful day!

[@eheath226]

Would you tell me what tailgate seal you are getting? I'm looking for one for my 2021 6.2 1500 at4 carbon pro. Your video's have been so helpful. Thank you.

[@nutzthomas]

Also interested in what kind of tailgate seal you come up with

[@nutzthomas]

Also interested in what kind of tailgate seal you come up with

[@Donslife]

This one here - amzn.to/44K0iQ4

[@Donslife]

This one here - amzn.to/44K0iQ4

[@Donslife]

Trying this one here - amzn.to/44K0iQ4

[@raulrodriguez4006]

I have seen parts of Texas at 86 and the highest is 93 at most on gas. Crazy how ppl put low end gas on expensive vehicles.

[@balgera79]

Perhaps price, here in British columbia. 91 octane is $2.19 a liter that's $8.27 a gallon.

[@RobustArid379]

How you fit a truck in 😊a garage

[@Donslife]

Carefully

[@Mr5875874]

Which exhaust you have and where can I get it. Thank you

[@Donslife]

This is the exact one I have : amzn.to/3Tr4hxZ

[@jfed1972]

I also have the misfires. Weekly. Codes never show up at dealership. Even when i pull it into service while the codes were going off they couldn't read it. I have been waiting 2 years for retro fit parts on a 2022..i cant even reset my oil change screen. So sick of gmc.

[@jumpinjimmyg2164]

Got a good Ole lifter smoker

[@joelpierce3940]

Sounds like my C7 ZO6

[@BarneyBrimlowe]

this guy has some weird chip on his shoulder. i don't get it.

[@toxicmasculinity6246]

GMC is great at making junk engines. Toyota 4.6L and 5.7L run circles around GMC.

[@slumy8195]

ive yet to see a gmc truck last past 200k miles without it being on its 2nd engine and trans

[@1R3VOLUTION]

@@slumy8195mine is close it’s the 5.3 192,xxx