2024 Gasser/Allison First Tow Report

the8rotor · June 12, 2023

On 6/9/2023 at 7:33 AM, lsttype said:

Finally towed my 9k camper with my 2020 6.6 gasser. Not trying to hijack thread. I just got rid of my diesel because of all the issues they currently have. Anyways I was very pleased with the power and I liked the 6 speed. I bet the 10 speed is even better. My wife has a 22 F250 with the 7.3 Godzilla but we are scared to tow with it because of all the lifter failures. We are so concerned we're tempted to trade it on a new GMC 6.6 gas with the 10 speed.

I loved my 21 gmc gasser as well! I'd hate to own an HD truck like your wife's ford and afraid to tow with it

Get her a 10 speed!!!

Doodle · June 15, 2023

On 6/8/2023 at 9:31 PM, UWSkier said:

wondering if you stayed in 7th or 8th gear at 65 MPH. On my 8 speed half ton, I run in 6th gear at that speed and feel I could most benefit from another gear between between 3 and 5.

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.

KARNUT · June 15, 2023

7 hours ago, Doodle said:

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.

If you ever had a tune, even a hand held. You wouldn’t believe how much performance is held back. So absolutely there’s constraints.

Doodle · June 15, 2023

7 hours ago, KARNUT said:

If you ever had a tune, even a hand held. You wouldn’t believe how much performance is held back. So absolutely there’s constraints.

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!

UWSkier · June 16, 2023

On 6/15/2023 at 4:34 AM, KARNUT said:

If you ever had a tune, even a hand held. You wouldn’t believe how much performance is held back. So absolutely there’s constraints.

I test drove a gasser/Allison combo this morning and was surprised how un-peppy it felt compared to my 2016 5.3L 8 speed, which doesn't exactly press you back in your seat either. I imagine the transmission would learn how I drive over time and respond a bit more. It felt like it needed a little more coaxing to scoot than the half ton.

Neither hold a candle to my programmed 2006 Titan though. Man, I miss driving that truck some days.

64BAwagon · June 17, 2023

I went from a 2018 1500 5.3 6spd to a 2021 3500 6.6 6spd to a 2024 3500 6.6 10 spd and I can say that every one was a step up as far as performance. While the 5.3 was okay it lacked throttle response (dead pedal) and the DOD/AFM was a PITA. Both my 6.6 gassers were more responsive. The best thing they did for the 6.6 gas was leave the DOD/AFM crap off of it.