TFL: 2016 Tundra vs Tacoma, towing mpg

[supton]

Fooling around last night, found this TFL video comparing 2016 Tundra Crew 5.7L vs 2016 Tacoma while towing 5,600lb in cold weather.



End result of the 100mile trip: Tacoma 8.4mpg, Tundra 8.2mpg.

Dunno how this would have fared if they tackled some hill climbs, but am guessing in the end, the extra 1,400lb of the Tundra would have again pulled down the mpg. Taco might have been slower, but more work to do = more gas needs to be burned.

But I found it interesting that, when not tasked at full load, the two were about the same.

*

I haven't been following trucks lately. Sad that Toyota is still behind. Toyota still hasn't figured out how to bring auto up/down to the windows. My 2004 VW had that, my 2011 Camry has it. I can easily deal without it on my 2010 Tundra but I'd pretty much expect it on anything new today.

38 gallon tank is nice, and I'm sure the integrated brake controller is nice too. Sidebar: the other week was really foggy up here, and I played with the headlight leveler. Setting it halfway down I thought made a big difference in reducing glare. Glad it's not automatic.

Is it me, or is Ken... behind the times? He keeps going on about the 4.3:1 rear end, and it's annoying. I don't know what Ford is using, but I know GM&Dodge have very deep first gears in their autos; the 6L80 is like 4:1, and the ZF's are even deeper. Toyota? try 3.33:1. I don't know what is better, deeply geared transmissions with a tall rear; or tall transmissions with deep rear ends. Direct drive on a transmission should be the lowest loss; I read in a book recently that planetary gearsets have higher losses when their gear ratios approach unity, so I want to say multiple sets have to be used in order get small gear spreads--meaning, all the more gears to mesh and lose energy. Yet those gears are in nice hot thin ATF, while the ring and pinion is in a thicker gear lube. So... ? Probably very small differences in reality. But Ken seems to not want to realize the role of the transmission, only "it's got 4.3's!"

He also made mention of setting cruise at 70mph. Don't know about the new Toyota's but I've found my automatic loves to run with the torque convertor unlocked in too tall of a gear. Meaning it likes to create heat & loss. Manually shifting down a gear forces lockup, and I have to wonder if a different driver, willing to use the controls, could better those mpg's. [Outside of towing at 70mph!] Then again, maybe not, as engine rpm seemed to be well above lockup speed for most of their trip. Sidebar: cruise on my 2010, in a word, sucks. It'll hunt all day on a hill. Maybe Toyota fixed that.

 

[hypervish]

Yeah, I wish they didn't use cruise control, but they do that so that comparisons are the same between vehicles. It makes for a semi-controlled speed in most of the cars.

I also think 70mph is too high atleast if you are trying to compare MPGs', but they claim that's the speed people tow at.

 

[supton]

You're right, I didn't think about that fact--that by using cruise it "standardizes" the test a bit.

Most people do seem to tow at posted highway speed. I know some states have lower speed limits for towing--I wonder if the test would show differences between the trucks at 55mph. The Taco would be working at that much of a lower percentage of power output.

 

[Ramblejam]

Originally Posted By: supton
But I found it interesting that, when not tasked at full load, the two were about the same.


Context is important.

Take a look at their respective EPA mileage. What's the percentage drop for each when towing this load?

 

[SwampSurvivor]

You can get 4.30 gears with the 6.2 in the F350 ...

 

[MNgopher]

F150 with the max trailer tow package has a 3.73 gear ratio, but 1st gear in the 6R80 is 4.17. The deep first gear is nice to get things moving, even with the higher axle ratios...

 

[supton]

Originally Posted By: Miller88
You can get 4.30 gears with the 6.2 in the F350 ...


Not a half ton though, and IIRC they did mention that in the film.

Originally Posted By: Ramblejam
Originally Posted By: supton
But I found it interesting that, when not tasked at full load, the two were about the same.


Context is important.

Take a look at their respective EPA mileage. What's the percentage drop for each when towing this load?


Tundra is 17mpg vs Tacoma automatic 23 or 24, depending upon option level. Interesting: the manual is rated for only 20 in the double cab configuration. And the Tacoma... can have 4.3:1 also, but only if manual trans or I4 (V6's get 3.9:1).

http://www.toyota.com/tacoma/ebrochure/

So the Tundra lost 52% and the Tacoma 63%. But... same cost to run loaded, and Taco is cheaper unloaded--it's city bests what the Tundra manages for highway.

 

[rslifkin]

Un-loaded, the smaller, lighter trucks will always do much better. Once they're loaded up with any significant size trailer (especially if it's one with a lot of wind drag), there generally won't be a big difference. And the bigger truck will generally pull the same trailer better.

Generally, the wind drag kills mpg far more than just the weight on a highway cruise. I've pulled another Jeep on a trailer behind mine, and with the other one facing backwards for better aero, I managed 11 - 12 mpg at 60-ish mph, even with plenty of big hills. I'd expect a bigger truck wouldn't have done much (if any) worse, as it would have been keeping more wind off the trailer with the bigger body and that likely would have made up for the extra weight, etc.

As far as gearing, there's an advantage to deep trans gears and tall diff gears. It ends up with lower driveshaft speeds at a given road speed, so it's easier to keep vibrations down and you might see slightly longer u-joint life. As far as actual towing performance, it doesn't matter either way.

 

[CT8]

It is just plain amazing that you double the load and greatly increase the wind resistance and the gas mileage drops.

 

[Nate1979]

Wind drag. Nothing more than that. Typical gas engine tow vehicles get about 9mpg when pulling high walled trailer such as travel trailers.

 

[supton]

In the vid they mentioned testing the 2016 Silverado next--but I couldn't find that video. I think that test would be interesting to see, an a/b/c comparison.

 

[supton]

Originally Posted By: CT8
It is just plain amazing that you double the load and greatly increase the wind resistance and the gas mileage drops.


Uhh, I'm not sure what you mean by that. Of course I'm not surprised that the mpg dropped. Geez... What I thought was interesting was that the trailer itself dominated, and brought both trucks to the same mpg. Despite one being 1,400lb heavier, and having an engine 2.2L (or 62%) larger.

In years past I've read to always get the bigger engine when given the option. The smaller engine will work harder under load, and get less mpg's as a result. Doesn't seem to be the case here. The bigger engine undoubtedly will get up to speed faster, and turn slower--but in this case, mpg is the same. Given the same task, two very different sized engines "cost" the same, dollar per mile.

Makes me wonder if the same result exists for the 3.6L Ram vs 5.7L Ram, for a moderate load, and same for Silverado 4.3 vs 5.3, etc. Old advice might no longer apply (always get the biggest engine!).

 

[Ramblejam]

Originally Posted By: supton
What I thought was interesting was that the trailer itself dominated, and brought both trucks to the same mpg.


My mom has a Murano. I have a Suburban 2500. Towing a small trailer, they'll both get approximately the same MPG.

At the end of the day, you just have to decide what's important to you, what you're going to be doing (frequency/weights/etc), and the sacrifices you're willing to make.

It's no different with the trucks here.

 

[IndyIan]

A 300hp V6 is a big engine!
I think the adage of the small engine being a dog in both power and mileage, is from the 90's and before. Back then, the smaller engine was likely to be an older, cheaper, less efficient design. 4 cyl wranglers come to mind...
Now almost every engine is nearly ideal, and quite efficient making 15% or 90% of its power, and the many speed transmissions allow it to run at a more ideal rpm.
With a 4 spd auto you could spend a lot of time bogging in 3rd or screaming in 2nd to get the right amount of torque to maintain your speed up a hill. Now the ECU can match engine rpm to torque demand in 2 or 3 gears and tweak the throttle without you knowing.

 

[rslifkin]

Originally Posted By: supton
In years past I've read to always get the bigger engine when given the option. The smaller engine will work harder under load, and get less mpg's as a result. Doesn't seem to be the case here. The bigger engine undoubtedly will get up to speed faster, and turn slower--but in this case, mpg is the same. Given the same task, two very different sized engines "cost" the same, dollar per mile.

Makes me wonder if the same result exists for the 3.6L Ram vs 5.7L Ram, for a moderate load, and same for Silverado 4.3 vs 5.3, etc. Old advice might no longer apply (always get the biggest engine!).


With the small vs big engine thing, it seems like when un-loaded, the smaller engines will do better for mpg (as expected). The bigger engine is running below its efficient operating range due to insufficient load, so it ends up taking more fuel to make the same power at cruising speed.

Once you load it up, the big engine now has enough load on it to be in an efficient operating range and the small engine is probably running towards the upper end of that range (might be pushed above it on the hills), so the fuel required to make the required power output at cruise is similar between the 2.

This idea is why the Ecoboost F-150s get a bit better mpg than the V8 trucks when running around empty (if you're not stomping on the throttle too much), but once you load them up, the mpg evens right out (reduced pumping losses from the smaller displacement are no longer a significant factor with the increased engine load).

 

[splinter]

It's not too challenging for me to manually select available ratios in my automatic gearboxes, 'tow' mode notwithstanding.

Aforementioned fuel consumption is typical and to be expected for a gasser hauling a decent load in my experience.
If one is getting a $100,000+ boat to playtime what difference does a few extra dollars make on the books?

Chevy, Ford and Chrysler make better trucks (properly optioned) for real truck duties imho.

 

[supton]

Originally Posted By: splinter
It's not too challenging for me to manually select available ratios in my automatic gearboxes, 'tow' mode notwithstanding.


That's what I do on mine, I will downshift before a hill that I know it will downshift on, that way it'll a) not shift under power, and b) have the torque convertor locked for the climb. It's how I can manage to hit EPA highway on my truck.

 

[hattaresguy]

Once loaded up all trucks burn about the same fuel. It simply takes energy to move a lot of weight.

For giggles if they tried that with a 3/4 ton I bet it would have gotten about the same MPG's.


You also have to remember that TFL tests their trucks at pretty high altitudes so they really are kind of worst case numbers.

 

[supton]

Yeah I noticed the cold temps in addition to the high altitude. Makes comparing NA with turbo motors harder--NA will do worse in their tests, but not quite as bad where we're closer to sea level.

Just another datapoint in the grand scheme of things. I still like my truck, even if it's on the low end of the totem pole.

 

[itguy08]

Originally Posted By: rslifkin

This idea is why the Ecoboost F-150s get a bit better mpg than the V8 trucks when running around empty (if you're not stomping on the throttle too much), but once you load them up, the mpg evens right out (reduced pumping losses from the smaller displacement are no longer a significant factor with the increased engine load).


Yup. Around town and unloaded (or loaded with people), I'll get 18-20 in my F150 Ecoboost 4x4 with Max Tow and 3.73s. Hook up the camper and it's 6-8 if you're lucky. Being 35' long, 11' tall and 8' wide does take its toll and makes that little 3.5L engine work like a 7.0L engine and gets about what a loaded F250 with the 6.4L would get under load. But it does it and does it well.