Tow Mode & Gears

[silver billet]

But how are you going to lug an engine with a modern automatic. The engine can detect when it is being "lugged" and it should downshift as needed.

I agree with you on towing, I do it based on performance and longevity not mpg savings, but in the end, if he is in auto and in T/H mode (which he says he does), it shouldn't negatively effect anything, at least not in any measurably way.

If he wants to be light on the throttle to get it to go into a higher gear while on a straight highway, not sure how that hurts anything while in T/H mode.

We just all have different definitions of lug. The computer always favours mpg it seems, when I'm pulling my trailer I hate to see the rpms below 2000. So yes it will definitely downshift, just not soon enough for my tastes. Perhaps "lug" is not the best word for this.

 

[IvoryHemi]

There is no way I would make it my goal to stay in 7th...which I believe is an overdrive gear.

Not sure which gear in the 8 spd is 1:1...

Yes 7th & 8th are both overdrive.

6th gear is 1:1

 

[Redfour5]

Actually, the manual states that you should be in the tow/haul mode even without a load in the mountains/hilly terrain, which will keep you in a higher rev range and extend the life of the transmission by reducing excessive shifting and heat buildup (pg. 287 of 2019 manual).

The computer will shift in a way that won't damage the truck. If you decide to lock the truck in 1st gear and drive at red line, that's a different thing.

 

[Redfour5]

Yeppers on having tow/haul mode in the mountains. In particular is coming down. The engine braking is far superior to having the guy behind you stare at your brake lights and YOU replacing your brakes way early and wondering what was wrong with the brakes. I live in MT and I am stunned at how few people know how to go down mountains. I do notice that many if not most don't have Montana plates. I see it with people towing and start to cringe wondering what they are going to do when they brakes finally give out... I've actually stopped a couple of times it was so bad. Why stop? I don't want to have to be behind them when they crash and burn and have to look at the bodies while I try to save them... I've seen them start to fade before, but thank goodness they design them so much better than 20 plus years ago.

 

[jdefoe0424]

I pulled a 6700lb 32' TT with a 5.7 3.92 1500 at one point. If you're drafting another big vehicle it may pull 7th up a slight incline, but most of the time it will need to downshift to maintain speed.
My 2500 feels a little less powerful but amazes me at how much the displacement really helps at lower RPM, the whole truck also runs much cooler. FWIW, I get roughly the same mileage pulling the camper with the 2500 as I did with the 1500.