Tow/Haul for a Uhaul 6x12?

[nc_beagle]

I hauled a Uhaul 6x12 loaded with furniture for about 300 miles of mostly interstate on Sunday. The base weight of the trailer is just under 2K and I would guess maybe 1K-1.5K of furniture in it. Any reason I should have had it in tow/haul mode? The engine only seemed to possibly be "lugging" in a short stretch of 45mph near the start, before the interstate. On the interstate, everything was good and it stayed in 8th gear for the majority of the trip.

 

[Johnny_H]

That’s easier than towing a broken down F150 which our trucks are designed to do with ease. I often forget to turn my tow/haul mode on towing 6-7000 pounds of boat, I seldom notice any changes in shift points etc. I’d ask if anyone really knows what goes on behind the scenes with it (different operating temps, changes to stability control, etc?).


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[IvoryHemi]

I use Tow/Haul even on small 3k lb loads for 2 reasons

1) downshift engine braking
2) keeps Eco off w/o using +\-

 

[nc_beagle]

I use Tow/Haul even on small 3k lb loads for 2 reasons

1) downshift engine braking
2) keeps Eco off w/o using +\-

Good points, though I don't have an Eco mode. In this case, I was driving from the SC coast to the NC foothills, so I never had any engine braking. I'll keep that in mind when towing moderate weights in the mountains, though I've had the engine downshift on its own coming down some long hills even without towing or being in tow/haul mode.

 

[nc_beagle]

That’s easier than towing a broken down F150 which our trucks are designed to do with ease. I often forget to turn my tow/haul mode on towing 6-7000 pounds of boat, I seldom notice any changes in shift points etc. I’d ask if anyone really knows what goes on behind the scenes with it (different operating temps, changes to stability control, etc?).


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Yeah, the only thing I know it does is the engine braking (like IvoryHemi mentioned) not just on hills, but on sudden, strong braking and it tracks towing miles in one of the screens on the gauge cluster.

 

[LoNeStAr]

I always use tow/haul mode when towing, no matter how heavy the trailer and contents.

 

[JC4041]

Crazy to think we used to tow things without a tow/haul button.

 

[tyromeo55]

Crazy to think we used to tow things without a tow/haul button.

True…. And before cars people walked.

Unless your forgetting about the buggy whip. Some might consider it the OG tow/haul mode

 

[Dookie]

...it tracks towing miles in one of the screens on the gauge cluster.

Interesting, I didn't know that. I use tow/haul as my default daily. I just prefer the manners of the truck with it enabled versus not. If I ever get rid of it, someone will think "OMG THIS GUY TOWS!"

 

[djevox]

I don’t have much to add except you can view the oil and trans temps in the instrument cluster display. If I were to tow a heavyish trailer, I would watch those and adjust accordingly.

 

[silver billet]

Good points, though I don't have an Eco mode. In this case, I was driving from the SC coast to the NC foothills, so I never had any engine braking. I'll keep that in mind when towing moderate weights in the mountains, though I've had the engine downshift on its own coming down some long hills even without towing or being in tow/haul mode.

ECO = MDS. Every hemi now has MDS, when you use tow haul it prevents MDS from activating.

 

[Eighty]

ECO = MDS. Every hemi now has MDS, when you use tow haul it prevents MDS from activating.

Just to be a pain in the rear...
The TRX is technically a Hemi. And it has no MDS.

 

[IvoryHemi]

ECO = MDS. Every hemi now has MDS, when you use tow haul it prevents MDS from activating.

OP has a 3.0L, so he has no Eco mode

 

[sdramsey24]

If I'm doing modest hauling/towing (4x8 utility trailer etc) I never use tow/haul mode mostly because I forget. When I tow my boat (19' open open bow and tandem axle trailer) or my travel trailer (27' box tandem axle) I ALWAYS use the tow/haul mode. Getting things rolling and more important, stopped, takes a bit less effort.

Some years back I was told that driving empty / unloaded with tow/haul mode engaged was bad for the truck. Is there any truth to that?

 

[Sascwatch]

I’ve towed empty and loaded up to 7000lbs with a 7x17 enclosed with additional height and don’t notice much difference on flat highway, but in town or through the hills I make sure tow/haul is enabled. Transmission temps run pretty cool on these trucks and the truck is smart enough to know when it needs to shift, it’s just a bit slower shifting without tow/haul mode enabled.

 

[HSKR R/T]

Yeah, the only thing I know it does is the engine braking (like IvoryHemi mentioned) not just on hills, but on sudden, strong braking and it tracks towing miles in one of the screens on the gauge cluster.

It will only track towing miles if you have trailer brake controllers and are using a trailer with electric brakes.

As for what tow/haul mode does, it hold gears longer when accelerating, downshifts when slowing down to use engine braking to help slow down. Disables MDS. Probably other little things it does behind the scenes

 

[HSKR R/T]

Crazy to think we used to tow things without a tow/haul button.

Used to be called OD off button on the older trucks with the 44/46/47/48 RE/RH transmissions. OD was always a weak link in those transmissions so you were supposed to turn it off while towing. People never read the owners manual to figure that out, so they switched the label on the shifter to read tow/haul so people would be more inclined to turn off the OD when towing. With the 545rfe and the new 8-speed trans that wasn't as much of a concern

 

[SpeedyV]

I hauled a Uhaul 6x12 loaded with furniture for about 300 miles of mostly interstate on Sunday. The base weight of the trailer is just under 2K and I would guess maybe 1K-1.5K of furniture in it. Any reason I should have had it in tow/haul mode? The engine only seemed to possibly be "lugging" in a short stretch of 45mph near the start, before the interstate. On the interstate, everything was good and it stayed in 8th gear for the majority of the trip.

I recently completed a 3,300 mile road trip, and probably 1,400 of that was towing a loaded twin-axle (6 x 12) U-Haul trailer. I noticed very little difference with Tow/Haul engaged or disengaged at 70-80 mph (3.92 gears). I was in 8th on flat stretches, 7th quite a bit with headwinds or gentle grades, and 6th on steeper hills. The truck would even go into MDS on gentle downgrades or with a tailwind. I tried Tow/Haul for a while and didn't see much of a difference in behavior, so I didn't really worry about it.

That said, when I got off the interstate and started running country roads with stop signs, state highways with stop lights, passing through small towns, etc.—then I engaged Tow/Haul all the time. The engine braking assist was fantastic, especially in less-than-ideal weather conditions. And the shift pattern just makes more sense in stop-and-go conditions.

 

[Richard320]

If I'm doing modest hauling/towing (4x8 utility trailer etc) I never use tow/haul mode mostly because I forget. When I tow my boat (19' open open bow and tandem axle trailer) or my travel trailer (27' box tandem axle) I ALWAYS use the tow/haul mode. Getting things rolling and more important, stopped, takes a bit less effort.

Some years back I was told that driving empty / unloaded with tow/haul mode engaged was bad for the truck. Is there any truth to that?

No.

I use tow/haul often, when I go on Sunday drives up in the mountains. It doesn't wait until it's lugging to downshift that way. It also compression brakes better on the downgrades. It will go into 8th gear if conditions are right and it does disable the MDS. I don't see how it's going to hurt anything. It's not like I'm locked down in 1st gear and winding it up to 60 mph

 

[nc_beagle]

It will only track towing miles if you have trailer brake controllers and are using a trailer with electric brakes.

That must be true. It didn't track mileage with this trailer which had some sort of hydraulic system that sensed forward momentum by the trailer. It does with my travel trailer.