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Downshifting while slowing down in Tow/Haul Mode

Lenny_B

By Lenny_B
in 6.6L Gas V8 (L8T)

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Lenny_B Enthusiast

Lenny_B

Posted
Posted

I have a 2022 LT with the 6.6 gas and have been overall happy with how it performs. I pull a boat around a lot that weighs about 5,000 pounds. This isnt much work for the truck and does everything great except when go to slow down say coming into a town, 60 mph to 30 mph, if I get off cruise and try to coast into town the truck wants to down shift to slow me down. Around 45 mph there is a very aggressive down shift. Is there anyway to turn this off other than not using tow/haul mode? The truck has plenty of brake to slow the boat down and the trailer has brakes as well so the down shift so aggressive is really not needed. I know it probably doesnt hurt the truck but it is uncomfortable to ride in, I have had other passengers make comments about it as well. 

Lenny_B Enthusiast

Lenny_B

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  • Author
Posted (edited)

so it says that tow/haul mode is designed to be most effective while towing a trailer at 75% of GCWR, that does not mean you should not use it correct? Also states that it will not hurt the vehicle to use Tow/Haul when lightly loaded or even unloaded. I feel like a 5,000 pound trailer is more than lightly loaded.

Edited by Lenny_B
Another JR Senior Enthusiast

Another JR

Posted
Posted

I agree with the OP that the downshifting in tow/haul mode when decelerating or descending is more aggressive than I would like for anything other than near maximum load.    

  • Like 1
Epsilon Plus Enthusiast

Epsilon Plus

Posted
Posted

I wouldn't be surprised if GM retuned it to be super aggressive after the crap showing in 2020 on TFL's Ike Gauntlet. The truck barely downshifted at all for them. My 2022 will drop gears like a professional trucker trying to brake an 80,000lb load (not a complaint, works great).

  • Like 1
Blatant Enthusiast

Blatant

Posted
Posted

i've used tow haul on super long down hills from time to time, not towing, to keep the truck holding gear, rather than messing with the manual shift.

 

  • Like 1
Flatus Enthusiast

Flatus

Posted
Posted

I don't understand the concern here. That downshifting is Tow/Haul doing it's job. This is completely normal. 

  • Like 2
Kjduvall Enthusiast

Kjduvall

Posted
Posted

Personally I really like it the way it is, I'll use it just hauling a bed load of fire wood and it's nice to have. I think everybody's perception of 'aggressive' is very different, and that's OK. I could take people for rides in my procharged/cammed/150 shot nitrous 1/2 ton Silverado and it would blow their mind...... But to me it was just a quick Street truck.

  • Like 1
Lenny_B Enthusiast

Lenny_B

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On 9/3/2022 at 8:36 AM, Epsilon Plus said:

I wouldn't be surprised if GM retuned it to be super aggressive after the crap showing in 2020 on TFL's Ike Gauntlet. The truck barely downshifted at all for them. My 2022 will drop gears like a professional trucker trying to brake an 80,000lb load (not a complaint, works great).

 

Do you think there is anyway to retune or possibly get the 2020 tune?

MORSNO Enthusiast

MORSNO

Posted
Posted
2 hours ago, Lenny_B said:

 

Do you think there is anyway to retune or possibly get the 2020 tune?

Tuners have pretty much been made obsolete by the feds, modern ones can do very little and as of recently the Banks PedalMonster which just makes your gas pedal more responsive has been the most popular.  

 

PedalMonster Throttle Controllers for Chevy, Ford and More – Banks (bankspower.com)

  • Like 1
Lenny_B Enthusiast

Lenny_B

Posted
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On 9/5/2022 at 11:55 AM, Flatus said:

I don't understand the concern here. That downshifting is Tow/Haul doing it's job. This is completely normal. 

 

I am not sure what you dont understand. I would like the downshift while slowing down to be less aggressive, similar to when not using tow/haul mode. I am looking for options other than just not using tow/haul all together. 

Texas1836 Enthusiast

Texas1836

Posted
Posted (edited)

Instead of using tow/haul you could put it in manual mode and shift down when you need it.

Edited by Texas1836
  • Like 1
Kjduvall Enthusiast

Kjduvall

Posted
Posted (edited)

Lennyb, just so you know there is zero tunning support for these trucks at the current time. That's why you can't tune for gear changes/shift points/ or any thing else for that matter. Our computer is encrypted just like the current C8. Other wise I would already have two walbro 450lph pumps and a tvs 2650 blower/ 1 7/8 headers, GPI cam with different fuel lobe+32 fuel lobe custom ground. To about 227/236 .610/.600 lift 110 +3 LSA and make around 680+ HP to the rear tire on my buddy's dyno. But the fact ove the matter is at this time we have no aftermarket support on this issue. About the best you can do is a muffler swap and a pedal commander (or equivalent device) to make it more enjoyable to drive. Just my .02¢ any way, happy wrenching bud.

Edited by Kjduvall
I can't spill worth a ******.
  • Like 1
Flatus Enthusiast

Flatus

Posted
Posted

I guess I just don't consider this downshifting aggressive at all. It feels just right to me. I had a 2015 F150 with 5.0/6speed and damn!! That thing had some seriously aggressive downshifting in tow/haul mode. I hated it. I just had to quit using tow/haul mode in that truck. 

Stand By Enthusiast

Stand By

Posted
Posted

The downshifting can be aggressive at times if you're feathering the breaking ahead of the transmission. By softening it up though, would probably increase friction and wear. A firm shift is healthier for a transmission. Soft shifting creates heat.

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