10-Speed Allison Transmission 101

Nick Priegnitz, CEO of DuramaxTuner, discusses the 10-Speed Allison Transmission found in the 2020+ 6.6L Duramax L5P. There is a lot of chatter out there about why this transmission was designed, whether that be good or bad, and we thought we'd give our 10 cents on this transmission. Nick touches on the benefits, where there may be faults and much more on this episode of Diesel Insights!

[samfixitguy]

I bought my 2021 Sierra 3500 Duramax 10 speed dually to pull trailers and 5th wheel campers and daily driving. Not to drag race. The stock power serves me very well for hauling my 17, 000 pound trailer. I have no need of the problems and headaches that comecwith modifications. I've had two previous Duramax/Allison's and I can assure you the 10 speed steps in and clears up the old 6 speed's shortcomings. Do not misunderstand, the 6 speed was an amazing, superb transmission. IN ITS TIME. 25 years ago. Very often it just didn't have a correct gear for a situation. Moderate speed in traffic. Engine was always either spinning too fast or too slow. Pulling up a hill the shift from 6 to 5 wasn't enough. It required dropping down another gear to 4th, which had the engine wailing unnecessarily. The 10 speed always has a gear to put you exactly where you need to be. Which means it is comfortable and pleasant to drive. For the last 50 or 60 years I have always been very conscious of what my transmission was doing. From the old "3 on the trees", 4, 5, 6 speeds. Manual or automatic. With this new 10 speed, it just doesn't matter. It always seems to know the right thing to do for what I'm doing. So I can pay more attention to important things. Like listening to critiques on my driving from the right hand seat.

[timskeuse]

I have a ‘20 L5P AT4HD and Nick nails it on the 10-speed. Very knowledgeable.

[yzmoto]

4 gears-4 year financing
5 gears-5 year financing
6 gears -6 year financing
10 gears- 😳

[someonethatwatchesyoutube]

No hyperbole. Calm informative presentation. Thanks!

[quagmyer]

I bought a 2021 Silverado 2500 HD Duramax to tow a 13k Lbs 39 ft long Fifth wheel, been cross country with it and have driven quite a few mountainous roads pass 10k feet of elevation (while towing that RV), we mostly use it for that and every time we need to haul stuff, I have no complaints, that truck feels smooth and effortlessly handles those mountains, I read somewhere that Allison engineers pointed out a few design flaws in it to correct before mass production, whether it’s Allison or not, I personally love the way it drives, I had a ‘04 Duramax 6 peed before and like this one better, fuel economy is also better, there is a huge difference between getting these trucks for a daily driver with a tonneau cover on it, and using them for their intended purpose.
I always tell people to get the brand they feel the most comfortable with, and get an extended warranty, things will happen regardless of brand, I just don’t get it why such rivalry between Ford, Dodge and GM owners, specially towards the “fake Allison owners”, do yourself a favor and ignore that, all brands have their ups and downs.

[hackfabrication]

Good video on the 10 speed. Especially the comments about being the the 'right gear' all the time. My current truck is a 2018 GMC Sierra 1500. 5.3L/6 speed. I'll be upgrading to a heavier duty truck within the next couple of years, so thanks for the info.

On a side note, I bought a new 2011 Jeep Grand Cherokee Overland. It had the 5.7L/5 speed. It was a good driving vehicle. In 2014, I traded for a Grand Cherokee Summit, 5.7L/ 8 speed. Big difference in diveability. The 8 speed shifted smoothly, almost un-noticed. In addition, it gave the driving impression that the vehicle was 'always in the right gear'. Bought a 2017 with similar specs, then a 2020 similar specs. All have/are good vehicles.

[jasonallin]

Wow, I will call the dealer shortly. They still haven’t completely told me what’s wrong and supposedly I’m next in line to get my truck fixed this week. Been sitting for 3 weeks now and service mama did say there is metal in my fluid. Thanks so much.

[keith]

I test drove a f150 ecoboost with a 10 speed the skip shifting in daily driver mode actually does make a nice driving experience on a daily

[Cody_Austin]

This is the best explanation of transmission tuning and why it’s necessary to compliment engine tuning I’ve ever seen.

[FlipCamFilms]

Great video and info thanks! I love my 2020 GMC Dually! 100k miles almost always towing something. Fantastic power, smooth shifts and surprisingly good mpg!

[ronaldbabbitt]

TCM Tuning is Awesome! A definite Upgrade Thanks Brother 🛠🏁☠️💨

[TheAverageJoeBro]

I wouldn’t buy this truck to run it down a track… I’d do exactly what it was designed for… tow with it. I appreciate this transmission and the design behind it. It’s a beautiful thing. If I wanted to race, hands down I’d go RAM TRX all day.

[rygi]

Bought a GMC 6.6 gas w/ the proven 6 speed trans after being a lifelong Ford guy solely because of all the negative feedback on the 10 speed reliability and excessive shifting. Awesome concept just thought I’d give them a few more years to work bugs out. I’m sure my next truck a 10 speed will be the only choice.

[broncobill]

I drive multiple 20, 21 and 22 Chevy pickups that pull massive loads with this ten speed. Seen tranny go out at 103k, 134k and when they did, they gave no warning signs at all. Basically they just had nothing left to hold on to get power to the ground yet. I hate how putting into manual shift mode it just automatically downshifts when I just want to be ready to before I'm actually headed down 8 percent grade loaded. Nothing more fun than trying to get it to upshift while at 3500+ rpm so you don't smoke something cuz it's really not meant that high.

[spaceghost]

The Freightliner semi I drive has an autoshift 12- gear trans. It is not a true automatic trans. with a torque converter, it's a manual with automated clutch actuation and gear selection. I have to admit I love this thing. I can select what gear I want to start off in. If I'm heavy it'll be 1st . If I'm light it'll probably be third. After a few miles the transmission will "learn" how heavy you really are. It will skipshift on it's own. It'll shift from 1st to 4th and then to 7th if you are light enough or if you are going down a grade. I think it has a gyroscope on it that knows the angle you're on. It does get confused on occasion and shifts before you would like but you can quickly flip the lever down and shift it. The fuel mileage is actually better than you would manage shifting it manually. I have driven them all. 9, 10, 11, 13, 18 speeds you name it. The 13 speed manual is the favorite of most semi drivers.

[duramaxadventures]

the F&F reference was GOLD! My real question is, Does a large displacement diesel NEED 10 speeds? or could OEM simply build stronger 6 speeds considering the power curve of modern VGT diesels.

[martinliehs]

Big diesel engines make lots of torque, but have limited rpm. That said, the majority of "real world" driving is done between 30 to 70 mph. In many ways, the more gears, the better (from a performance point of view). However, the biggest priority for a transmission in a heavy duty truck application is longevity. The real question is, will these 10 speed boxes hold up for hundreds of thousands of miles (and millions of shift cycles)?

[jeffpiatek]

Had a 22 f250 with the 10spd and 430 gears, Hated it. Back to a 17 with the 6spd and love it. Such an awesome transmission.

[GXYZ]

I tow a large heavy (for an RV) 5th wheel with my new Ram, the Asin 6 speed with the HO Cummins works fine in my opinion. I also think it's heavier duty than the GM and Ford 10 speeds. I'm sure the 10 speeds are okay, but I sure don't worry that I don't have one.

[robertmathias-qmoz]

FYI. I have a 2021 3500. When in drive it starts out in 2nd gear, but in tow/haul it then starts out in 1st. 23mph empty / 13 towing. Love it all day long.