After 1.5k miles tow

I’m almost done with my trip LA to New Orleans, 1.5k miles so far.
I had a 2013 Rock Worrior crew maxed and we did lots of towing with it.
Now hybrid crewmax 4x4.
Ride and power is not even on the same league, I forget that I have the trailer behind many times.
Now my problem is MPG. Same trailer
Just different trucks and I’m getting the same if not wore mpg with the hybrid that I did with the 5.7. I try 87, 89 and 91; It’s about 0.5 mpg some times 1 mpg better with 89 or 91, the engine felt way better on 89/91. Speed 65-70 mph most of the time and I’m averaging 8.5 mpg sometimes it goes up to 9.
I can’t figure out why the mpg are the same on both trucks.

 

Your setup looks awesome!

The fuel mileage isn't any better because you have to work that V6 harder than you did your naturally aspirated V8. For a smaller turbo engine to make high power it not only needs a lot of air, you have to have a lot of fuel as well.

 

Also, unlike a diesel, the torque/HP come on much later in the RPM band. Higher RPM = more fuel consumption...

 

This makes sense, I guess been a noob on a turbo engine I had different expectations I was hoping 11/12 mpg. But I’m extremely happy with how it handles.
Also the way the electric engine works may need some reprogramming, I would say that at least 90% of the time the truck runs only with the turbos. The battery was full and I was going uphill on a constant speed and the truck wouldn’t use the battery, the only way to get the battery to engage was to let go os the acceleration and accelerate again then the battery would kick in and help on the hill. Not sure if it is programmed to be as reserve in case you need the extra power. I was just expecting the battery to help more often. Again me been a noob

 

Actually most of the time rpm were at 2.2k, on the whole trip maybe 6 times the rpm ramped up and was really quick. Not like the 5.7 that was screaming most of the time.

 

There are a lot of variables that are tough to account for between your previous towing with your 2013 and your new 2022. Some can contribute to the lack of improvement in towing economy. The only real way to test them would be same trailer, same speeds, same day(s), same traffic, same weather etc over your route.

Plus your new truck is just that: new. There have been some observed reports of these trucks improving after getting some miles on them. Whether it’s break in and seating of parts, the ECU and TCU learning, or some other voodoo the phenomenon can’t be completely ignored or discounted.

Even if your towing economy remains essentially identical to your old 5.7L powered truck it’s probably still a win. As you noted the new iForceMax tows better because it has a ton more power. Just chugs along at 2.2K RPM on that fat wave of torque. Then when you’re not towing it’s probably capable of way way better average fuel efficiency than your old 5.7L so at worst you’ve gained a lot more power for towing, equal towing fuel consumption, and significantly improved unladen fuel efficiency. Best case you get better towing efficiency too as the engine, transmission, and axle differential gears all wear in and smooth out.

Thanks for the info, keep us posted.

 

I like the big red air splitter mounted on the roof.

 

I think your mileage is pretty realistic considering your speed & might improve with break in of the engine.
I found the sweet spot for mileage on my 2008 CrewMax was around 2,000 RPM’’s while towing, which equaled about 62mph depending on terrain. I don’t like to tow much faster & tow a 7,000lb Airstream loaded for camping. My mileage was always around 9-10mpg. My 2008 always performed better on 93 octane while towing. My Hybrid Platinum is due in October, so I appreciate the real world info on a very similar sized travel trailer.
Safe travels & keep us posted on your trucks performance while towing. Not many have posted this type of info to date & I’m sure there are many people interested.

What is your payload # for your Hybrid???

 

I think that's a wire cutter

 

I don't generally go over 65 mph when towing for a myriad of reasons as I know it won't stop as quickly and your aerodynamic drag goes up exponentially above 60 mph with a trailer that's shaped similarly to a brick. It's worth trying to keep it under 65 mph and see how your mileage does if thats what your chasing. A buddy of mine could care less about mileage and just wants to get there so he hauls ass with his trailer but winds up stopping more often for fuel, all depends on your timeline.

Do you have towing mirrors? I don't and wish I did for our trailer...

 

The transmission is a big difference here.
With 10 gears its much easier for the motor to get just a few extra rpm. With the 6speed it had to kick down way farther to build rpms.

 

LA to New Orleans? I know it was over 100 F in many parts of the southwest. That definitely can drop your fuel economy if you’re running your AC cold.

 

Wouldn’t matter for the 5.7L even if it had the 10 speed. Peak torque for the 3UR-FE is at 3600 RPM. The transmission would select whatever gear it had that put the engine closest to peak torque. That’s what the 10 speeds behind the Ford and GM V8’s do, same for the Ram 8 speed.

Even unloaded if I’m climbing a hill with anything at or above a 6% grade my Tundra always grabs 4th gear at 70 MPH. So it’s turning about 3300-3400 RPM, and it just stays there.

For example this GM wants to hold a gear that gives 4,000 RPM. Coincidentally peak torque is right around 4,000 RPM on both the 5.3L and 6.2L V8’s.

 

yup, and the more gears it has the closer it can stay right there all the way through the power band.

I was impressed the new one peaks at 2,400 , thats pretty damn good

 

I thought the electric assist was just to help with off the line acceleration, so if you aren't in stop/go situation it shoudn't be doing anything.

 

The hybrid motor is there to supply extra torque and HP when needed based on driver input/conditions. Low speeds under roughly 20 mph, the hybrid motor runs. Taking off from a stop, clutch engages for hybrid motor and sends you the max torque, accelerating to pass, hybrid helps out. The peak torque hits at around 2400 rpms. The hybrid motor was designed specifically to provide low end, diesel like torque performance. They did not design it for fuel economy. You will run off your combustible motor for pretty much everything not mentioned above. It isn't the same hybrid design as you see in the prius.

 

I have yet to get on a highway with my trailer but I was expecting/hoping the hybrid will be working to maintain speed up hills and things like that if required. It’s great for filling in the gaps low speed and almost eliminating that abrupt feeling of engine start/stop. If you drive in sport mode its right there on demand with instant power.

That said if I end up in a situation where I feel like the truck is struggling to pull a trailer and the hybrid is not kicking in I will be a little disappointed. Those spec sheet torque numbers would be kind of meaningless.

Does the hybrid motor kick in differently based on tow vs. tow+ modes?