Toyota Tundra as a Tow Vehicle

[GettinAway]

Pulled the 23FB FC on Sunday for the first time with the Tundra.. Nice!
First time I've actually felt like I've had enough power to pull properly. I can tell it's back there, but it's not pushing or swaying my TV.
We have always had to downshift, turn off the AC, and slow down, or really rev the engine. Really nice change. Pulling from Mo down to Florida in a few weeks. That'll be first all day test on mpg. Then this summer near Leadville Co, that'll test the hill climbing and descending abilities.
Very comfortable so far.
Jeff


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[KJRitchie]

I'll be interested in you mileage too comparing my 2wd vs your 4x4. I hope you get 11s to 12s if you drive 60mph. Unless it's very flat roads keep it on S with 5th as the highest. I wish the gas tank was a little bigger than 26 gal.

I'll be taking mine out west to Utah in June returning via I70 through Denver then back to Missouri. I'll try to take an Ike Gauntlet video with my phone. I suspect 3rd gear to maintain 60mph up that grade towing my Classic 25fb.

Kelvin

[Gene]

5th is also overdrive, so I wouldn't lock it in to 5th as it might cause even as big an engine as the Tundra's to lug a bit. The computer is more efficient than we can be in choosing gears and although I prefer a stick shift, I have surrendered.

Gene

[azflycaster]

Gene, It's not locking it into 5th, it's just preventing it from shifting into 6th. I took a ride with Andy Thompson a few years ago and he suggested the same thing. At 60 towing, the engine lugs in 6th gear and the gas mileage falls off. I do this often im my Tundra. If I am towing in the 65+ MPH range, 6th gear works fine.

[ROBERTSUNRUS]

Hi, not trying to highjack this thread, but wanted to mention a few things in common. Many of the trucks like mine came with a 26 gallon gas tank. I was happy that mine came with a 36 gallon tank. Also I have read to lock out sixth gear while towing. So far, I haven't had the chance to tow with it yet, but hopefully soon.

[m.hony]

Originally Posted by azflycaster

Gene, It's not locking it into 5th, it's just preventing it from shifting into 6th. I took a ride with Andy Thompson a few years ago and he suggested the same thing. At 60 towing, the engine lugs in 6th gear and the gas mileage falls off. I do this often im my Tundra. If I am towing in the 65+ MPH range, 6th gear works fine.

In Drive it will eventually shift into 6th given a downhill run or a flat road and no wind or a tailwind.
Are you saying I should manually shift into 5th?
I get 12-13 leaving it in Drive.

[TG Twinkie]

I have an '08 Tundra 2WD. Tow a 26' Argosy.
I use Tow/Haul and the "S" mode. I find that using 4th as the high gear limit and running 60mph gives me the best mileage. I will on occasion shift it up to 5th as the limit. But it has to be pretty flat and little head wind.
In 4th a 60mph the engine is at about 2,800 rpm.
The mileage rarely drops below 12mpg. I average 13-14mpg and have recorded up to 18mpg in the valley near El Centro, CA. Where it is below sea level.
I rarely use cruise control because when there is a drop in speed below the set point. The throttle goes to the floor until the set point speed is reached. This has a huge effect on the mileage.


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[Gene]

m.: yes, using the S mode means manually shifting.

To others, maybe I should look at the owner's manual and read up more on the transmission. Richard, I never thought of that, but I see no reason (except my ignorance) that it should lock the transmission.

Toyota cruise control does have a bad habit of punching the pedal at max to get up to a set speed, so I usually increase the speed manually (or footually) and then turn on cruise. I find that if I let up on the pedal when I set the cruise, the speed drops about 2 mph, so I keep my foot on the pedal for a few seconds after I set the cruise control control (I like that better than "cruise control button").

Bob: I think the Chevy and Ford both have a 36 (more or less) gal. tank and have had so for several years. No idea about the Dodge (or Ram or whatever). I would like to have a bigger tank, but it means I have to stop sooner and walk around. That is good for me. Since we have a tendency to drive too far before stopping to unkink, a 10 gal. tank would be even better, but the nice thing about a big tank is you can get out of California and buy cheaper gas.

Gene

[GettinAway]

I'll experiment with cruise control, and using S in 5th. I'd have to get used to 2800rpm in 4th, that seems like a high rpm. However, if it gives me a few more mpgs then it's sure worth looking at. I would like a 36 gal tank, but it's not important enough for me to switch away from Toyota. I've been brainwashed, drank the cool aid, whatever you want to call it. Knock on wood, we've just had so much better results with durability and reliability with Toyota. I wonder what the business plan looks like that makes you assemble a vehicle that will run forever, trouble free, and still hope to sell you another one in a few years??

[Goal15]

I will be the first to admit that I'm not an expert on all things mechanical, but towing at 2800 rpm at 60 in 4th seems odd. I tow at 60 in drive and am only at about 1500 rpm..... it would seem to me that running the engine at nearly twice the rpm would result in less gas mileage, not more.

Can someone explain this? 2800 in 4th seems like a strain on the engine

[macofpei]

I leave my truck in D with the Tow Haul button depressed. I let the computer chose the correct gear for me and I get between 13-15 miles per gallon, depending on my foot. If I drive at 60, I get great mileage. If I drive faster, the mileage drops to as low as 11.5. Again, I let the computer chose the gear, I have to chose the speed. I do not use the cruise control as I like to have control, while towing.

[Gene]

Dana, I can't see how 4th would work better than 5th if you are so significantly increasing RPM. But people drive at different speeds and have much different trailer weights—we go 65, but I notice when we are driving on 2 lane highways with lots of hills and curves and can't go more than 40-45, our mileage goes up. Because all the posts on mileage are anecdotal, I'm having a hard time sorting out what applies to our situation.

Can't easily beat the Tundra on reliability, but others are catching up to Toyota. Latest JD Power ratings had GM products as the only US companies in top 10. Now at 99,300 miles and no need to buy another truck, but someday we will. I'd like to wait for a recession which lowers prices, much better gas mileage and want to have more choices than the Tundra. We've had 7 Toyotas and all have been extremely reliable, but more choices is a good thing.

Gene

[KJRitchie]

Originally Posted by macofpei

I leave my truck in D with the Tow Haul button depressed. I let the computer chose the correct gear for me and I get between 13-15 miles per gallon, depending on my foot. If I drive at 60, I get great mileage. If I drive faster, the mileage drops to as low as 11.5. Again, I let the computer chose the gear, I have to chose the speed. I do not use the cruise control as I like to have control, while towing.

Is that hand calculated on the US gallon or Imperial? Best I've gotten is 12.9 mpg on one leg of a trip between Lafayette, LA and Mobile, AL. Flat, little wind. Towed at 60 the whole leg. I only use cruise for about 10 minutes to rest my foot. Is yours 4x4? Do you use regular or premium?

Kelvin

[TG Twinkie]

My logic in driving at 60mph in the "S" mode and 4th.
At 2,800 rpm, it may be 2,600rpm. The engine is not working hard or lugging. When meeting a head wind or hill the engine rpm will change slightly (200rpm or so) based on the load and the torque converter locking in. The transmission does not shift back to 3rd causing higher rpm.
When in 5th or 6th under the same conditions the throttle is depressed more to maintain the required speed. One can hear this by the deep howling sound of the engine working trying to maintain the required speed. It is a sort of lugging sound. And the transmission routinely shifts down or up. causing rpm changes. The fuel mileage suffers under this condition.
Cruise control magnifies the problem by opening the throttle fully when the required speed is not met.
When I was a young man I was trained to drive 18 wheelers. Part of that training involved having a glass of water on the console. One was required to shift and brake without slopping the water out of the glass. I was taught to drive as though you had a raw egg between your foot and the throttle pedal. If you push down on the throttle too fast or hard you will break the egg. Broken eggs means depleted fuel mileage.
The man who taught me how to drive received many annual awards for getting the best fuel mileage of any driver in the company.
Over the weekend I completed a 380 mile round trip to Denver from my home. Driving 68 mph (not towing) in "D" mode. My average mpg for the trip based on the computer readout was 21.9mpg. Calculation based on the amount of fuel I put in the truck resulted in 21.3 mpg. Elevation changed on the trip from 4,100 to 6,400 feet. Half of the trip was on 2 lane Hwy, speed limit 65. The other half was on interstate HWY , speed limit 75. I drove no faster than 68mph.


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[Goal15]

Originally Posted by TG Twinkie

My logic in driving at 60mph in the "S" mode and 4th.
At 2,800 rpm, it may be 2,600rpm. The engine is not working hard or lugging. When meeting a head wind or hill the engine rpm will change slightly (200rpm or so) based on the load and the torque converter locking in. The transmission does not shift back to 3rd causing higher rpm.
When in 5th or 6th under the same conditions the throttle is depressed more to maintain the required speed. One can hear this by the deep howling sound of the engine working trying to maintain the required speed. It is a sort of lugging sound. The fuel mileage suffers under this condition.
Cruise control magnifies the problem by opening the throttle fully when the required speed is not met.
When I was a young man I was trained to drive 18 wheelers. Part of that training involved having a glass of water on the console. One was required to shift and brake without slopping the water out of the glass. I was taught to drive as though you had a raw egg between your foot and the throttle pedal. If you push down on the throttle too fast or hard you will break the egg. Broken eggs means depleted fuel mileage.
The man who taught me how to drive received many annual awards for getting the best fuel mileage of any driver in the company.


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Thanks for the additional info. I'm going to give it a try on my next trip. I guess I had just assumed that by towing the way I was, with lower rpms that it would be better for the engine over the long run because it didn't seem to be having to work as hard.

Dana

[m.hony]

Can I really expect an improvement? I get 12-13 hand calculated mpg now.

[KJRitchie]

I know in 6th gear I have to press a little more on the accelerator pedal to maintain speeds on slight hills then it shifts to 5. If you switch your system monitor to instantaneous mpg you will see the mpgs drop every time you depress the accelerator pedal even just a tad. So when I discovered locking out 6 didn't seem to hurt mileage because it didn't have to press the accelerator pedal as much, I started using 5 more. I've notice in 5 the rpms just under 2000 rpm at 60mph. The engine rpms will go up if you press the accelerator a little more but it won't shift down to 4. I suppose keeping it in 4 would keep the rpms more constant and you wouldn't be pressing down on the accelerator pedal as much to maintain 60. Maybe I'll try this on one leg on my trip out to Utah in June. The only issue might be its a little noisier in the cab.

Kelvin

[m.hony]

I usually leave it in drive, set cruise, and let her rip.

[Gnorts]

Originally Posted by m.hony

I usually leave it in drive, set cruise, and let her rip.

There ya go. I do the same. 12 to 12.5 mpg. 50 on 2 lanes, 55 on 4. I try not to over-think the issue.

Looking back on the old F150, from many moons ago, 351 Windsor with the C-6 3-speed slushbox, towing an 18ft Caravel of half the weight, hunting and shifting uphill, freewheeling and riding the brakes downhill, 6 to 9 mpg, we're in hawg heaven in this Texas Toyota.

We love our Platinum. We call it "the cowboy Cadillac."

[m.hony]

Our neighbor just got 14 mpg on the way to the rally in Vicksburg. He is towing a 1986 32' behind a new Ford Expedition.
We got 13 on our last trip to Texas with our 30' behind the Tundra.
I can't imagine better fuel economy than that, not even in a diesel.