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I apologize if this has been asked before, didn’t see it but if the new 10 speed proves to be a stout transmission, and since the 2020 shares the L5P engine with previous body style, would this ever happen?
 

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I apologize if this has been asked before, didn’t see it but if the new 10 speed proves to be a stout transmission, and since the 2020 shares the L5P engine with previous body style, would this ever happen?
The trucks you reference do not have a 10 speed. The 10 speed is new to the 2500 line for 2020. Looking underneath the 2020 vs the 19 they are not the same GM did some other changes as well. If that is what you mean. Biggest issue on trying to retrofit thing is SOFTWARE. Just not going to happen. GM has absolutely no interest in doing it for obvious reasons and there is no aftermarket call for these types of things. Vehicles are much more software centric than in the old days.
 

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They also changed the rear end to match the 10L1000. New ratio is 3.42:1. Easier just to go buy a 2020.
 

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It's a good question man. I have a new 2019 3500 and wondered the same thing.

Who knows. Couple of years and that new tranny would have been been dissected by diesel nerds across north America... and we will have answers.

Let's also see a new tranny that makes 250k. My lml I just traded in had 100k with zero problems. Proven trans.
 

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Discussion Starter · #9 ·
The trucks you reference do not have a 10 speed. The 10 speed is new to the 2500 line for 2020. Looking underneath the 2020 vs the 19 they are not the same GM did some other changes as well. If that is what you mean. Biggest issue on trying to retrofit thing is SOFTWARE. Just not going to happen. GM has absolutely no interest in doing it for obvious reasons and there is no aftermarket call for these types of things. Vehicles are much more software centric than in the old days.
I don’t want to be an arse but I don’t think some of y’all can read...I even stated that the 10 speed is on the 2020 and up...I was asking IF AND THATS A BIG IF it proves to be a great transmission, and someone wanted to put it on the 17-19 body style if it was possible. The rear end gear ratio going from 3.73 to a 3.42 would not affect much, if anything it will give you better response low end being geared down. They still share the same ecm and tcm...the tuning is obviously different but I can’t imagine a 10 speed tcm tune would be difficult to pair up to the previous engine as the changes in the L5P are minute.
 

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I don’t want to be an arse but I don’t think some of y’all can read...I even stated that the 10 speed is on the 2020 and up...I was asking IF AND THATS A BIG IF it proves to be a great transmission, and someone wanted to put it on the 17-19 body style if it was possible. The rear end gear ratio going from 3.73 to a 3.42 would not affect much, if anything it will give you better response low end being geared down. They still share the same ecm and tcm...the tuning is obviously different but I can’t imagine a 10 speed tcm tune would be difficult to pair up to the previous engine as the changes in the L5P are minute.
Well if you were a Good Reader and did just a little bit research you would see that not only is the fluid different, cooler size and lines, mounting points for the transmission etc. etc. you would quickly understand that well, never mind. Knock yourself out.:) SMH
 

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Im sure it will be a thing at some point, but this early in the game... doubtful.
 

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I wish I could still order a 2021 with the trusty Allison 1000 6 speed instead of this new name only 10 speed. The new 10 was not fully designed by or built by Allison. GM pulled a fast one by having Allison allow GM to still use the name on this new transmission no doubt at a price. GM stands to save tens of millions making the new trans totally in house. Looking at the 2 units side by side it really appears in new tranny is not as stout. I have dragged heavy equipment, large RV's all over, up and down mountains with the old 6 speed and it never misses a lick on top of that even going up and down grades and mountains it rarely downshifted or dropped out of overdrive 4 more speeds were not needed. The duramax is such a stout and has so much torque it really didn't need a 10 speed. I was at the Allison service center earlier in the week getting a spin on filter for my 6 speed. I asked the parts guy about parts available for the new 10 speed and was told "its an Allison in brand name only". It has no parts manufactured or supplied by allison and no parts for it will be available through allison. They don't even have any documentation for it. I thought it was funny the 6 speed is still available for the 4500 and 5500 and not the 2500 or 3500. As I understand it the Allison will soon be available for the Dodge w/cummins, this will be a real game changer for Dodge. I think when the real truth comes out about the so called "allison" 10 speed GM will be sorry they went this route. The future should be real interesting on this...
 
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The Allison in the MD trucks is different than the ones in the 2500/3500 trucks
 

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The 6 speed was one of the reasons I bought a 19 instead of a 20...

Don’t get me wrong the 10spd may turn out to be a great transmission but I plan to keep this truck for awhile and didn’t want to roll the dice on a new platform. The Allison 6 is proven.
 

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I apologize if this has been asked before, didn’t see it but if the new 10 speed proves to be a stout transmission, and since the 2020 shares the L5P engine with previous body style, would this ever happen?
2020 silverado avg 15.2 mpg at 29500 miles. Pulling about 5-6k every weekday. Highway and city. Pretty smooth so far. Switched up from a 2016 1500 ram which got 7-9 mpg avg.
 

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I guess time will tell, we can only hope this was not another GM cost cutting effort and instead a real effort to enhance the duramax 2500/3500 platform. I think at this point I would go the same way as Cencal. I must say calling the new trans a 10 speed Allison is a real boondoggle and misleading on GM's part, I hope this bites them in the ass.
 

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Well for me with over 40k so far the 10 speed is a dream. Could not run fast enough to give me the old tranny or the lower DEF tank that gets holes knocked in it off road rendering the truck useless.
 

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I'm at 22k so far, highway mileage is pretty good so far I've had multiple tanks of 21-23mpg traveling 75-78mph here in Texas. How that relates to transmission is just better efficiency by keeping the RPMs in power band. Towing wise, the 10spd hasn't missed a lick so far seems like its always in the right gear and is smoother through shifts. The only thing people have really complained about is the engine braking because the 10spds dont jerk you down like the 6spd does... its just much smoother.
 

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One thing is for sure there are so many low mileage 2019's available now because many with the 6 speeds want the new 10 speed thinking the towing, performance, fuel economy and max pulling power has been increased. I drove a 2019 3500 crew/short bed and a 2021 same combo and have to admit the 2021 was smoother. Performance wise they were so close I could not tell the difference. What I did notice though at highway speeds and on a grade the new 10 speed seem to downshift more to try to stay maybe in a power band where the 6 speed stayed locked and just pulled which I liked better. There is difference when using the engine brake as well. The 6 speed allison seems to be much more agressive in downhill braking and feels like it applied more of a braking force then the 10 speed

IMHO considering all the factors i'm currently in the market for a 2019, I trust the 6 speed, it has a proven record. To me the 10 speed is overkill with a bunch more parts internally that can break in it. On external observation it also looks like a car transmission then a heavy duty truck unit like the 6 speed does. I also like the more agressive engine brake on the 6 speed and the fact that once it shifts into high it just pulls and stays in that gear.

Add to that I dont really see any performance gains nor fuel economy differences in any of the independent reviews at this point and my seat of the pants can't tell any difference in acceleration.
Im happy so many have bailed for the new tranny and possibly the technology so it's a buyer's market right now and there are some great deals to be had. I also like the fact the 2019 is almost a foot shorter making it easier to get into the garage.

My only real disappointment is that I would not be able to take advantage of the new camera system or tailgate that's on the 2021's. Oh well sometimes you just have to make concessions. I really do hope the 10 speed really works out, it would be so sad is Dodge would take over the top slot because they will offer a true Allison in their 2022's. Time will tell.
 
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Didn't mike L take one apart? I think the 10 speed is rated for a lot more torque over the 6.... one of reasons I assume they went with them and for future proof... 6 speed seemed to be end of life for power handling....

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