2020 3500 hd Allison transmission

Pfc1 · July 27, 2019

So we are thinking about going to a new truck. We currently have a 2018 2500hd duramax and we are thinking about a 3500. We will be purchasing a new camper and I think we will need more truck. Now I'm reading that the 10 speed tranny in the 3500 is not really an Allison but just branded. ??? Does anyone have any information on this, I certainly would appreciate it. I am ready to pull the plug on this whole thing. The Allison transmission is a tried and true hd transmission and the ideal combo for the diesel, thanks.

DemonWorks · August 5, 2019

Last time I was in GM Training, this topic came up. The instructor was 100% certain on the transmission being a GM Trans, however, Allison was obviously paid gobs of money to run their name but Allison wouldn't just allow their name to be used if they didn't feel it was a well built transmission. it is my understanding, Allison was presented the transmission and they went over it and gave their full seal of approval. With that, i would be ok with the new 10 speed.

Additional info - It was explained that Allison did not feel a 10 speed was necessary and that is why they did not built it in the first place.

Wintersun · August 5, 2019

What do you mean by your need for more truck. The 3500 only increases load capacity with DRW and you can get the same results with a SRW by adding a $500 set of SuperSprings over the standard leaf springs. If I needed more than 4,000 lbs of payload with my 2500HD I would swap out my wheels and tires for 19.5 ones rather than go to DRW.

DRW is needed with a 16,000 lb plus 5th wheel trailer to support the weight on the hitch. Easiest for the factory to add two more 3200 lb rated tires to increase payload and this is reflected in the slight difference in price of the 3500 that only adds the two wheels at the rear and a second set of leaf springs.

I would expect far lower resale value of a DRW truck as they are less desirable when not towing a huge trailer down the highway. On my travels I often count the number of 5th wheel trailers pulled by SRW versus DRW trucks and 80% of the time it is a SRW truck that is being used.

newdude · August 6, 2019

On ‎7‎/‎27‎/‎2019 at 2:43 PM, Pfc1 said:

So we are thinking about going to a new truck. We currently have a 2018 2500hd duramax and we are thinking about a 3500. We will be purchasing a new camper and I think we will need more truck. Now I'm reading that the 10 speed tranny in the 3500 is not really an Allison but just branded. ??? Does anyone have any information on this, I certainly would appreciate it. I am ready to pull the plug on this whole thing. The Allison transmission is a tried and true hd transmission and the ideal combo for the diesel, thanks.

For future reference, there is an HD section on the forum for the 2020 HD.

That out of the way...Yes the 10 Speed "Allison" is an in house GM built transmission. Allison WAS involved in its development, validation and testing, hence why it wears the Allison branding/badging. Allison tested and validated the 10L1000 transmission to their specs for GM. Due to GM's long time partnership with Allison, they were able to maintain the relationship but on their in house unit. The 10 speed also allowed GM to retune the torque management to allow full engine power in 1st gear. The current setup with the Allison 1000 6 speed, the L5P is power restricted in 1st gear.

https://www.youtube.com/watch?v=lBocpjvch8M

https://www.allisontransmission.com/company/news-article/!details/2019/01/23/gmc-to-offer-10-speed-fully-automatic-allison-branded-transmissions-in-2020-sierra-heavy-duties

https://gm-techlink.com/?p=11703

Edited August 6, 2019 by newdude

Pfc1 · August 6, 2019

Thank you for the information. I've also read that gm has been building ALL of the Allison transmissions in house since 2006 but I'm not sure if that's true or not but I get it. Recently it seems like divesting lessons ones responsibilities In the business world. So they owned Allison at one time, then brought the manufacturing in house then sold the business but not the transmissions that they now build. I know I'm very satisfied with the 6 speed in my 18, I guess it's only going to get better.