Towing with new 6.4L

[MEGA HO]

A rule of thumb, if tranny is hunting for the gear too often, use T/H.
When I had my little 4500# loaded travel trailer, I didn't use T/H as there was no difference at all in how my truck performed, but then I've got a diesel so YMMV.

 

[RPS1030]

Hey all!

I have a ‘21 3500 CCLB 4x4 with 3.73’s. I put the first 500 miles on it empty and then I just towed a small 4,000 lb travel trailer almost 600 miles. The first 500 of that was the “break in” tow @ an agonizing 50mph. I got 14mpg, then on the last 100 miles I got 12mpg doing 60-65 mph.

Doing 50 mph and being 10K + under the tow rating I noticed in tow/haul the truck would basically not go above 6th gear, and ECO would never come on. Turning off tow/haul would get me 7th gear and ECO on downhills. In very hilly or city traffic I’d leave it in tow/haul for the better engine braking.

On the 60-65 mph leg of the trip I left it in tow/haul and the truck would stay in 7th most of the time with an occasional 8th gear on downhills. ECO was a rare sight.

Does anyone know at what weight tow/haul is “required”? Is it a mandatory feature to use with a trailer on the small side?

A rule of thumb, if tranny is hunting for the gear too often, use T/H.
When I had my little 4500# loaded travel trailer, I didn't use T/H as there was no difference at all in how my truck performed, but then I've got a diesel so YMMV.

Yup, what ^ said. If it’s shifting frequently or you don’t like the shift points, change the Tow/Haul mode.

I know in my old truck, there were a handful of occurances where the hill descent downshifts were holding way past the steeper section and trying to get it to upshift took taking it out of Tow/Haul. And once or twice on long straight stretches were it was staying in 5th (6 sp 6.4L) I dropped Tow/Haul to get top gear

 

[jdefoe0424]

We took a long trip to go see family. TT was probably 7-7200 lbs, another 3-400lbs or so in the bed.

Overall average after ~2,300 miles (~300 w/o TT) was 9.1 MPG. That number would have likely been better but we took an alternate route on the first leg home to have a more scenic drive...well worth it though.

 

[JohnWedell]

We drove back from Florida in March towing a 16,000 pound fifth wheel RV. We stayed in cruise control most of the way not going any faster than 65 mph when the speed limit allowed it. Averaged 8 miles per gallon and was pretty happy with that. truck perform great even though it was a 6.4 hemi very happy with it. Ordered a new truck, a 2022, basically the same truck 3500 Dooley CC, 6.4, 4.10, 8 speed transmission, I’m hoping to get better gas mileage with that.

 

[RAM_Dad]

We drove back from Florida in March towing a 16,000 pound fifth wheel RV. We stayed in cruise control most of the way not going any faster than 65 mph when the speed limit allowed it. Averaged 8 miles per gallon and was pretty happy with that. truck perform great even though it was a 6.4 hemi very happy with it. Ordered a new truck, a 2022, basically the same truck 3500 Dooley CC, 6.4, 4.10, 8 speed transmission, I’m hoping to get better gas mileage with that.

16k 5er with the Hemi…I can only imagine how much it screams going up an incline. Thats definitely Cummins territory, the exhaust brake would do wonders towing that load.

 

[JohnWedell]

It really doesn’t rev that much. Usually 4500 RPM going up a hill. I really don’t need a diesel because we drive to Florida in December and drive back to New York in April the rest of the time I just drive it around town. I don’t need the expense or aggravation of a diesel but thanks for the suggestion

 

[RAM_Dad]

It really doesn’t rev that much. Usually 4500 RPM going up a hill. I really don’t need a diesel because we drive to Florida in December and drive back to New York in April the rest of the time I just drive it around town. I don’t need the expense or aggravation of a diesel but thanks for the suggestion

That makes sense, I could see it being ok for a few mostly flat hauls a year.

 

[raven_dt]

After reading these comments I'm hoping that I get 9mpg (hand calc) when we head out next month to the Smokys. I took our 7k TT out this weekend to finish adjusting the wdh. A little concerned about the need to downshift and mpg coming out of a 7.3/3.55 on the short loop.

 

[Firebird]

My 6.4 ranged from 8 to 9 mpg depending on terrain, 4.10 gears

 

[gimmie11s]

I don’t need the expense or aggravation of a diesel but thanks for the suggestion

But you need the expense, aggravation, lack of parking, and stiff ride of a one ton DRW? If youre going to pay the DRW penalty (and there is a DRW penalty, several actually), then you may as well get the engine that belongs in it.

 

[Bob_ag]

Not towing, but did some hauling the other day. One pallet (42 bags) of 80lb quikrete bags which was roughly 3,400 lbs with the pallet. My payload on the sticker is a little over 3,200 so I was close to 200 lbs over payload. Truck is a 2019 CC Tradesman Hemi, pretty much stock other than tires.

Gotta say, that's probably the best the truck has ever rode. Smooth drive home, truck didn't even sweat, but I sure did unloading it.

 

[Rockcrawlindude]

Cruise set to 83 pulling around 7000lb I got just under 10mpg this weekend. Not bad for warp speed. I can easily get 11 or 12 with this same load if I drive 20 mph slower

 

[Jenky21*2500]

Needing input on this - I have a 2021 2500 6.4 with 8 ft bed, and 3.73s. Max payload is 2849 lb / 14,020 5th Wheel hitch max trailer rating per the VIN.
Looking at a 5er = 2365 hitch wt / 11,041 Dry wt. at 39 ft. We have a TT now (7,000 lbs) but debating on going to the 5th.
Should we forget the 5er and stay with the TT? Never had a 5er before. Of course, the RV dealer says no problem.

 

[RAM_Dad]

Needing input on this - I have a 2021 2500 6.4 with 8 ft bed, and 3.73s. Max payload is 2849 lb / 14,020 5th Wheel hitch max trailer rating per the VIN.
Looking at a 5er = 2365 hitch wt / 11,041 Dry wt. at 39 ft. We have a TT now (7,000 lbs) but debating on going to the 5th.
Should we forget the 5er and stay with the TT? Never had a 5er before. Of course, the RV dealer says no problem.

You absolutely need a Cummins for that trailer. And if you upgrade to a Cummins, then a 3500 is the logical choice.

 

[jdefoe0424]

You absolutely need a Cummins for that trailer. And if you upgrade to a Cummins, then a 3500 is the logical choice.

Not necessarily, seen plenty of people pulling trailers that and heavier with the 6.4. It also depends where you're driving.

Needing input on this - I have a 2021 2500 6.4 with 8 ft bed, and 3.73s. Max payload is 2849 lb / 14,020 5th Wheel hitch max trailer rating per the VIN.
Looking at a 5er = 2365 hitch wt / 11,041 Dry wt. at 39 ft. We have a TT now (7,000 lbs) but debating on going to the 5th.
Should we forget the 5er and stay with the TT? Never had a 5er before. Of course, the RV dealer says no problem.

Look at the GVWR of the 5er, I'm guessing it's around 13k. 13k multiplied by 20% is 2,600lbs, so if you fully loaded the camper up that's what your pin weight could be.
Keep in mind that the stated hitch weights usually don't include any batteries, propane tanks and may not include other stuff that is installed by the dealer.

Now, add up the weight of the things in the truck. You, wife, kids, pets etc...it adds up quick and only a lighter 5er will make the payload numbers work with a 2500. IF you care about staying within the legal numbers of the truck.

 

[LateToTheParty]

Needing input on this - I have a 2021 2500 6.4 with 8 ft bed, and 3.73s. Max payload is 2849 lb / 14,020 5th Wheel hitch max trailer rating per the VIN.
Looking at a 5er = 2365 hitch wt / 11,041 Dry wt. at 39 ft. We have a TT now (7,000 lbs) but debating on going to the 5th.
Should we forget the 5er and stay with the TT? Never had a 5er before. Of course, the RV dealer says no problem.

With that hitch weight, you're absolutely going to go over your payload. Realistically, with three 165lb passengers each bringing a single piece of beef jerky, with nothing else in the truck or the trailer, you are at your stickered maximum.

If you're one who adheres to guidelines and rules, you'll be breaking them. If you aren't, not a concern on that front.

Will the truck pull it - sure it will. Will you or the truck be happy doing so, nope.

If it were me, I'd stick with the currently owned truck paired with the currently owned TT. But if you have the $$$ for a new truck to pair with that new 5W, then by all means it is time to go big.

 

[Jenky21*2500]

Thanks for the inputs. I will most likely stick to my thoughts (with the wife) and insist on the 3500 DRW is needed, or at least preferred. We are happy with the
TT we have and the truck handles it easily. Should have went with the DRW I looked at when I decided on the 2500.

 

[gimmie11s]

Needing input on this - I have a 2021 2500 6.4 with 8 ft bed, and 3.73s. Max payload is 2849 lb / 14,020 5th Wheel hitch max trailer rating per the VIN.
Looking at a 5er = 2365 hitch wt / 11,041 Dry wt. at 39 ft. We have a TT now (7,000 lbs) but debating on going to the 5th.
Should we forget the 5er and stay with the TT? Never had a 5er before. Of course, the RV dealer says no problem.

Truck will pull it, but you will not be impressed on anything other than flat ground at sea level altitude.

Also, that pin weight is around 25-2600 lbs so considering your payload of 2849, you will not be legal once you and one other person hop in the truck to leave for vacation.

Legalities aside, I wouldn't want to be pulling almost 40 foot worth of trailer with a 3/4 ton/coil spring truck, but that's just me.

 

[Vapor567]

Needing input on this - I have a 2021 2500 6.4 with 8 ft bed, and 3.73s. Max payload is 2849 lb / 14,020 5th Wheel hitch max trailer rating per the VIN.
Looking at a 5er = 2365 hitch wt / 11,041 Dry wt. at 39 ft. We have a TT now (7,000 lbs) but debating on going to the 5th.
Should we forget the 5er and stay with the TT? Never had a 5er before. Of course, the RV dealer says no problem.

I have a short bed '19 6.4. towed a 28' travel trailer with about 8-8.5 mpg. Switched to a 5th wheel 37' but pin weight was only listed at 1750lbs, GVWR 11500. The truck pulled the 5th wheel much easier and returned around 9-9.5 mpg running at 65-66mph. Your truck will handle the 5th wheel fine in my opinion but if you go diesel you'd have to jump to 3500 for more payload. As a side note, the 5th wheel was incredibly easier to tow and more stable using an Andersen Ultimate. However, I really disliked not having the bed of my truck for storage. Last month we sold our 5th wheel as we're wanting a cabin instead on land but if we get another camper it will be a bumper pull without a doubt.

 

[MEGA HO]

Not necessarily, seen plenty of people pulling trailers that and heavier with the 6.4. It also depends where you're driving.

Look at the GVWR of the 5er, I'm guessing it's around 13k. 13k multiplied by 20% is 2,600lbs, so if you fully loaded the camper up that's what your pin weight could be.
Keep in mind that the stated hitch weights usually don't include any batteries, propane tanks and may not include other stuff that is installed by the dealer.

Now, add up the weight of the things in the truck. You, wife, kids, pets etc...it adds up quick and only a lighter 5er will make the payload numbers work with a 2500. IF you care about staying within the legal numbers of the truck.

You forgot to include the weight of a 5th wheel hitch itself which will eat up the remaining payload leaving nothing for the driver and passengers.
You surely could pull that much weight with a 6.4 but would you want to? I wouldn't