Doodle

I think this 10 speed is the best transmission I’ve ever had in any vehicle. I have a 15 LML with the 6 speed Allison and it’s fantastic too, but this 10 speed is more refined IMO. Only thing it does sometimes is downshift kind of harshly when coming to a stop. Not all the time, just occasionally. Like it gets confused which gear to drop too. Guess time will tell on reliability but if they put this transmission behind the diesel I can’t imagine any situation where you could hurt this with a gas engine. Just keep an eye on the temps and should last a long time.

The 6 speed is a great transmission as well. I think the 10 speed keeps the 6.6 in the power band a bit better but I had no issues with the 6 speed in my 23. Main reason I traded my 23 for a 24 was I got an AT4 and my 23 was an SLE. I like the looks of the SLE but I hate the fact you can’t get a console and leather seats with the SLE. With the Chevy you can upgrade an LT with those options. I guess as I get older I just want to be more comfortable. Plus I have three kids and there was two cup holders in the whole pickup. Didn’t even have the rear seat flip down. I honestly think the 6.6 gas will end up being a very reliable engine. I’ve honestly never heard of anyone having any issues with them other than some oil consumption. They have been out 4 years now so there are some with over 100K for sure somewhere. My only complaint is the fuel mileage. I wished it was better but these things also weigh a lot and sit way up in the air. So far the 10 speed is no better than my 6 speed. I was hoping it would be a bit better. It does seem to do better with non ethanol gas. Most of the time I never see any significant difference with my 5.3’s on E10/15 compared to regular but for some reason this 24 seems more sensitive. Problem is E19 vs regular 87 around here is about $0,60-0.70/gal cheaper so it doesn’t really make economic sense to run regular.

I think the 6.6 gas is going to be just as reliable as the 6.0 gas in time. I have had a 23 with the 6 speed and now a 24 with the 10 speed. I will say the 24 will pull as much as my 2015 Duramax, it will just get terrible mileage (6-7 mpg). I pulled this trailer the other day and I was grossing 30K total combined. I should have never loaded this heavy but only had to go 25 miles. Pulled the load at 65 no issues other than watching the gas gauge drop. My lifetime mileage with 10K on the 24 is about 12.5. My Duramax has a lifetime of about 14.5 with 130K on it. However it’s actually cheaper to run the gas with the current fuel prices. I’ve never had any oil consumption issues. Only complaints I really have with my 24 AT4 is it has lots of little dash and interior rattles. Might just be because of the stiffer suspension but it’s kind of disheartening with what we pay for these things. I would not buy a new diesel again unless I was towing all the time. That’s where diesel shines. I tow seasonally, but heavy. The 6.6 will get the job done but it’s definitely not a diesel as far as torque goes. I would have to think these new 6.6 gas should easily hit 150K with minimal issues at all. The new 10 speed is butter smooth and a big improvement over the 6 speed in my opinion but the 6 speed was good too.

Had a 23 put 15K on now have a 24 with 10K. Mileage is about the same. My 23 was an SLE and weighed about 7150 lbs. My 24 is an AT4 and weights a tad over 7500 lbs plus it has the 20” tires. So given that I’m glad it’s about the same as the 6 speed. I would not pull the trigger just for mileage. The 10 speed is just a more refined trans and is just makes the power so much more useable. The more miles I put on the better I like it. Butter smooth shifts too. My 23 took to about 10K to get broke in so the mileage could go up a tick, but I”m guessing very minimal.

Yeah there are so many factors when it comes to mileage. Every blacktop road around here is minimum 65 mph. We are flat and wide open in western KS. Nothing like Vermont. If I drove 55 here I'd feel like a snail! I also live at 3500' elevation so that makes a difference too, but the flat geography does help mileage. Where I live there are essentially no hills and what we might call a hill people back east would laugh at. No such thing as "steep grades" here. Ha ha.

To be fair I don't think my LML would do much better than 17-18 at 80 mph. In my area diesel is approaching $1.50/gal more that gas. So it's still cheaper to drive the 6.6 gas than the diesel right now. Kind of glad I have both. Just let the LML sit unless I need to tow heavy.

Another update on mileage. I took my 24 on a 600 mile roadtrip all highway this past week. I was fighting a little wind from time to time (I live in Kansas) but I was traveling between 69-80 depending upon if I was on the interstate or state highways. I noticed once you get above 70 mph mileage really starts to drop. At 80 I was getting about 14-14.5 roughly. At 65-70 closer to 16-17. Think my average tank was about 15 or so on that trip. Kind of disappointed in the mileage at interstate speeds as it’s holding 10th gear fine, but also realize these things sit way in the air and are heavy. On one flat stretch I put it on 60 mph cruise just to see the difference and it was closer to 18-19. Only 7K on it so far. My 23 started to get a little better around 10K so guess we’ll see. Also the first tank of fuel I ran was 89 octane. Just wanted to see if there was a difference. I guess I’d say there was no noticeable difference.

I have had the same experience. Have a 2015 diesel, had a 23 6.6 gas, and now a 24 6.6 gas. Towing 6000 lbs is nothing for the gas. I live in western KS where it is flat, but I have no issues pulling 12-14K with the gas. Once you start getting up to 16-18K a diesel will be better. The 6.6 gas can do it, but it will rev a lot and gas mileage will be 6-7 at best. My 24 gas actually has a higher GCVWR than my 15 diesel. That is primarily due to the frame and brakes, but the diesel will definately pull heavy loads much easier, but it does show the gas is more than capable. I can speak to experience on the 6 vs 10 speed. They are both great transmissions. The 6 speed was more than capable. They 10 speed just keeps the 6.6 in a better powerband when towing. I actually thing the 6 speed was quicker unloaded than the 10 speed but towing wise the 10 speed is better in my opinion. The 6.6 gas has been out since 2020. So far they have proven to be very reliable, much like the 6.0 gas. Not saying the L5P isn't reliable, but if you do have issues it's gonna take big dollars out of warranty plus the $10K upfront cost. Mileage wise I get 12.7 with the gas and my 15 LML I'm 14.5-14.7 average. With our local fuel prices that's a wash plus I don't have to use DEF or additives with the gas. If I towed heavy all the time I would get the diesel as the economics would work out better for fuel mileage. I might tow 5K a year. Not worth it for me to have two diesels. The newer diesels are monsters for power. If you like or need that you will not like the 6.6 gas. If you just need something reliable with cheaper upfront cost that will still get the job done I'd go for the 6.6 gas. I have said many times I wish GM would come out with like a 7.0 with 450 hp/500tq and that would start to close the gap a bit between gas and diesel. Maybe with some tuning that's already attainable with the 6.6.

My 24 is very accurate as well, Best computed average I’ve ever gotten with a GM product. I’m at 5000 miles now and was hoping unladen mileage would come up. Best I can get pure highway is maybe 16.5-17. My lifetime average is 12.7 so that’s not bad with a mix I guess. My 15 LML only gets about 14.5 average so with the cost of fuel it’s a wash. My 24 gas AT4 CCSB weights almost 7600 lbs empty. My LML SLT CCSB weighs 7850. These new pickups weigh quite a bit more and they sit up so high in the air, mileage is just gonna suffer some. For reference, I had a 2008 LMM CCSB that only weighed 7200.

Great comments and feedback. I have not towed with my 24 much yet, but I actually do like the transmission compared to the 23 6 speed I traded in. In my opinion the two transmissions are totally opposite. The Allison gets a heavy load moving easier, but seems to get real busy once up to cruising speed. The 6 speed was doggy to me getting started but would hold power better once up to speed IMO. With the 6 speed i generally never saw it shift much out of fifth with a load, the 10 speed will shift all the time and I really don’t know what gear it’s in. But the Allison does perform well, it’s just a different driving experience. The Allison is butter smooth so if you aren’t paying attention to the rpm’s you really don’t know it’s shifting much. I would not fear pulling up to 26K in my area with the gas, its just mileage is gonna be 6-7. I still have a 2015 LML so most of the time under heavy tows I’ll just use it but the 6.6 gas can do it. I do feel like GM left some on the table with this engine. I know whipple came out with a new supercharger, but it’s like $7500 so that make no sense, might as well get the diesel.

I have not experienced this with my 24 but you can definitely hear a little more “noise” with this transmission compared to the 6 speed I had. Not annoying or anything but it’s there if you listen. My feeling though it because the pickups are so quiet now. Hardly hear the engine.

The computer actually read 15.1. The 15.2 was hand calculated. I’ve never had a GM read low. Always at least a half mile or more optimistic.

Just got back from a 900 mile roundtrip (unloaded) with the new GMC. Running anywhere from 69-80 depending upon which highway I was running on. Averaged about 15.2 mpg which I was pretty happy with overall. Still at less than 2500 miles so might get better in time. I think if I ran 65 this thing would get 17-18 pretty easy. Amazing for a pickup that weighs in at about 7500 lbs and is way in the air with 20" wheels. I was really impressed with how well the transmission keeps the 6.6 in the powerband. It cruises effortlessly on the interstate and I can pass with ease with just a blip of the throttle. The 6 speed had no issues either, but you can tell this transmission is just more refined and in tune with what the engine is doing. The more I drive this thing the more impressed I am with it. I think if GM ever came out with something like a 7.0L gas with 450-475 hp and 500 tq with this 10 speed, there really wouldn't be a big reason to get a diesel unless you were towing heavy all the time. The 6.6 gas is great but I just think they would grab a big chunk of market share if they had something with just a touch more power. But then I'd probably just say "I wish they made 500 hp" so it probably wouldn't matter, lol.

I wouldn’t worry much about 7.3 gas. Internet causes people a lot of grief Most of the time shouldn’t worry about. I have a 2015 LML with 130K and people act like they are all destined to blow fuel pumps. I know it happens but it’s a small percentage just like lifter failures on 7.3’s. If it happens to you then yeah it sucks, but the chance is likely small. Having said that, I’m happy with my 24 gas and it is a great platform. My 23 didn’t use any oil and I don’t have enough miles on the 24 to report if it uses oil yet.

I once put a Blackbear tune on my 2005 6.0 gas. It woke it up significantly. That was with a 300 hp 4 speed!

I just towed a decent load with my 24 today. It was only like 11,000 lbs but it was the first thing I've towed. At 65 mph it was pretty much staying locked into 7th/8th. Running about 2100 rpms. It would drop to 9th every once in a while, but wouldn't stay there long. In comparison my 23 with the 6-speed would pretty much stay locked into 5th running about 1800-2000ish from my memory. I really wish GM would let us know what gear we are in. It's very annoying. The Allison is so smooth shifting that unless you are watching the rpms's you don't really know it's shifting. The 10 speed is "busier" than the 6 speed but not annoyingly so. It does keep it in the power band. To be honest with you if felt like maybe I was being held back a little on power. I wonder if GM has some programming in the ECU for the first few thousand miles on towing. I only have 800 miles on at this point and I know as my 23 got more miles on it performance and mileage got better. I just feel like at times it could have easily ran in 8/9th gear but kept it up more in 7-8. Reason I say this is my 23 would hold 5th almost all the time unless encountering a hill when towing weight like this. It will be interesting to see how this pans out. I watched a few videos on YouTube of JB Reviews and he kind of mentioned the same thing. He felt like performance was getting better with more miles on his 24 gas. There is no doubt the 10 speed is helping keep the gas engine in a tighter power band though. I can't believe how smooth this transmission is. GM did a great job with the tuning. Not clunky at all. My 6 speed was a little clunky at times when slowing down but did shift very smooth as well.

Beautiful pickup! I really think this new platform is gonna take some market share away from Ford and Ram for this segment. The more I drive mine the more and more I like it.

I do definitely notice some “whine” with the the new Allison. Nothing annoying, but it’s there. I finally got the pickup to the dealer today to diagnose that “noise”. The tech could hear what talking about, although faint, and went to his computer to check any TSB’s. About five minutes later came back with a document that pretty much to a tee summed up what I was experiencing. It was PIT5544G for those that want the specifics. Some customers may comment on a hydraulic rush or flow type noise from the power steering gear. The noise is most noticeable in the cab at idle, with all accessories off. It only affects vehicles with RPO code NV8. Basically it’s noise from the Active Hydraulic Assist Power Steering system. So GM considers this “normal”. So I don’t really care to hear it but it is what it is I guess. You only hear it in park or idling with the radio and HVAC off so I guess it’s not a huge deal. This L8T is so quiet I imagine on the diesel you’d never even hear it. But so far thats the only issue I’ve had and thats pretty minor in the scheme of things. Really loving this new platform.

Great write up and I agree with many of your points. Although I haven’t actually towed with my 24 yet, I am loving this transmission. It is butter smooth. I also agree if I had a 6 speed I wouldn’t run out and trade it off because of the 10 speed but the 10 speed is a nice upgrade. I towed some pretty stout things with my 23 gas and it performed well.

Couldn't agree more. We both grew up at a time when you put in long hours and sacrifice to get ahead. Seems like that mentality is slowing fading. If there is one piece of advice I tell my kids and young adults is don't get discouraged about life. Turn off social media and especially the news. There are a "ton" of opportunities out there if you are willing to hustle. Don't let people tell you there isn't. Those are just the ones that either never took a chance or are just mad about where they are at in life. It's not easy by any means but if you work hard, treat people with respect, and conduct business with the highest integrity, you will win almost everytime. I'm living proof. Off my soap box now. Lol.

Best way I can explain it is it's like when the fan speed in on low and you have the vents shut off. Like a restricted vent sound. Faint, but it's there. Here's the super weird part. I only hear it at idle and as soon as I hit the throttle it goes away. I think that's why I never noticed it when I drove it home from the dealer.

The light switch you literally cannot see at all because the steering wheel blocks it. I realize they are auto lights but it's a dumb place to put it regardless.

Ha ha. Again nothing wrong with the 23 at all. My issue all along was I had ordered a 22 AT4 in July of 21 and it never got picked up. Knew the refresh was coming and decided I would wait. However, needed to put a pickup on service for my business so bought the 23 knowing it wouldn't keep it too long. No way would have thought it would show up this fast. We'll see how the 24 does and I'll update when I can.

I have to admit when I wrote the check for the 2024 I was like what the heck am I doing trading off a 23 i've had for six months! And on top of it I had 0% from GM on the 23! I kind of took a bath on the trade but this is the pickup I wanted for two years. I'm 46 and I grew up pretty humble. Have worked my tail off for 20+ years. Went many years just getting by with what I had. Ten years ago would never ever considered a pickup like this. I always got the LS, LT, SLE trims till I got the 2015 SLT. The older I get I realize life is short and if you work hard you need to reward yourself everyone once in a while or what's the point. My 16 year old son thought I was nuts trading the 23 off but he said whatever you want to do, you deserve it. Kind of made the decision for me. Financially it's dumb but I love vehicles and I plan on keeping this one a while. But I agree it's crazy how many people finance huge chunks of these vehicles now days. I was very fortunate I could pay mine off as GM's rate for HD's is around 6% right now!

Well I got the new AT4 last weekend. Been so busy this week didn't even have a chance to drive it much. Basically drove it home from the dealership and parked it all week. We had some stormy weather and I didn't want to take the chance of getting damage the first week! I liked the 2023 and had zero issues with it (14,****** miles) but I will tell you this 2024 is the nicest vehicle I've ever owned. It's everything and then some what I read. The interior in the 23 was fine. The 24 is just a step change. Just like when I went from an 08 LMM to my 2015 LML. I thought at the time I'd never own a nicer pickup. Still love the 15 and will keep it, but the 24 is way more refined. Literally to the point it's honestly too much tech and creature comforts. I've never felt like I couldn't take a pickup off road to work in, but I'm contemplating this one. Probably good they kept the Pro with older interior for those situations where guys need more of a work truck. I'll give some quick thoughts after only 250 miles of driving: Pro's: Interior is amzaing! 10 speed is for real. I cannot wait to hook up to a trailer. The transmission grade brakes like my LML. Buttery smooth and seems to be in the right gear. The transmission is "somewhat" busy but I never really notice it. Never saw the trans temp go over 165. Exterior is the best looking pickup on the market bar none. The new Ford is ugly as sin in my opinion. Technology is out of the world Fuel mileage seems to be up a tick from the 6 speed. Averaged 17 on the trip home (65-70 mph). It took my 23 about 10K miles to break in so I expect this one could hit 18 highway in time. To me that's amazing. Cameras are amazing. Can see everything crystal clear. There is even a washer on the front camera! Con's This thing sits up high. Maybe it's because of the 20" wheels but I"m 6'4 and I almost need steps to get in. My wife almost had to use a step ladder and she's 5'7. First thing need to do is get some steps installed! I sort of like where they put the trailer brake control but the light and 4wd switch on the left hand side are in blind spots. I don't like that at all. Honsetly can't even see them. GM should have put a little more thought into positioning. Already have one strange noise coming from behind the dash. Almost like a faint fan noise. Gonna take it back next weekend to the dealer but that's always the fear with a new model comes out. Honestly there isn't much to dislike with this one (other than the price). As I get a few more miles on it towing I'll update but I can guarantee already it will be better. This transmission is going to be a game changer. Really no reason to go diesel now unless towing all the time or in the mountains. I'm in flat country. The 6 speed was fine for me, this will be better. I think GM is gonna pick up some market share with this refresh. If you are on the fence about upgrading I would take a hard look. Only 250 miles so time will tell but I am very pleased so far.