New guy to the 6.4 universe

[Ali G]

Hey peeps new to the group I’ve got a 22 6.4 big horn wondering if there’s any mode to improve my towing experience?

 

[whitexc]

Welcome. Little more info is needed. What are you towing? How far? How often? Might be a wrong truck issue. Might be getting used to a new truck issue.


Sent from me

 

[Msmmce1]

I have a 2021 6.4 3.73 and tow a 32' 7000lb travel trailer and I've found I like the drivetrain characteristics towing NOT in tow haul mode with 8th locked out. I find that it downshifts much less and is a more drama free drive, temps stay in check.

 

[Pasta4lnch]

I have a 2021 6.4 3.73 and tow a 32' 7000lb travel trailer and I've found I like the drivetrain characteristics towing NOT in tow haul mode with 8th locked out. I find that it downshifts much less and is a more drama free drive, temps stay in check.

Interesting - wouldn't have thought to do that. Curious, were your temps going high in tow/haul? I'm also new to 6.4 w a 10k# 38' camper. I've only gone short distances so far so I haven't pushed it...

 

[Dave01]

I think 10k is a bit of a different animal from 7k. I tow 8,000 lbs fairly often and at times forget to put it in tow/haul. While it doesn't have trouble pulling it, I like the shift pattern and especially downshift pattern better in tow/haul. I'd prefer to have a gas engine rev rather than shift early and lug at lower rpm, feel like it's better for both engine and transmission. Just my take. But for 10,000 lbs. I think you're getting into a weight range where you'll really need to use tow/haul with a 6.4.

 

[Pasta4lnch]

Good to know - I've only gone short distances on relatively flat surfaces. Putting it through the paces this summer for sure!

 

[Gondul]

2019 6.4 with 3.77 and tow a 32' TT 9000# (ish)...
The only time I use tow/haul is when I'm getting it rolling or I'm stuck on surface roads.
Once I hit the highway, I turn it off and lock out 8th gear.

She'll run in 7th or 6th most of time... if it seems like it's hunting, I'll lock out 6th but that's just in really hilly areas.
Oil is usually at 220, 230 going up a good hill....
I swear the Trans temp never seems to change...

 

[WildBill138]

I know on 1500s towing in 4th+overdrive aka non tow mode will destroy the transmission. High gear is too weak to pull and will start breaking things. Im guessing that is the reason for the trans doing what it does in tow mode.
I dont like the excessive downshifts going downhill with a trailer but i also dont tow heavy, and am over geared. 4.10s with tradesman 29" tires.
So to have normal shift patterns but not use 8th gear by limiting it to 7/8 on the gear selector seems like a reasonable solution.
Maybe someone in the transmission clan can explain it better, or maybe they would get banned for letting out secrets..