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Hi All,

Here's a comment and question that was sent to us from a forum member:

"As much as I am happy with my 5.7 Toyota gas mileage has not improved or changed since 2007 (for the 5.7L). Does Toyota intend on making any modifications to the gasoline drivetrains to improve fuel mileage to where it is closer to the competition? If so will these changes hamper the performance/power of the trucks?"

Answer:

Well, the fuel mileage is competitive with other vehicles in its class, when compared to real world conditions and owner testament as reported on third party sites. Of course, there will always be a tradeoff for power vs economy. There are benefits to small displacement, forced induction engines. But again, the tradeoff is an engine that must work 25% harder (6 cyl. vs 8 cyl.). And, the additional work creates additional heat, especially under the hood. The smaller displacement reduces the engines pumping capacity, in turn reducing the engine's ability to use that capacity for engine braking while towing. There is no replacement for displacement.

Thanks and keep sending us your questions.

Bob,
Program Manager for Tundra Vehicle Development
 

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I would suggest Toyota engineers respond to fuel economy requests the same way I have. Ignore them and increase horsepower instead. :D

Individuals wanting fuel economy from full sized trucks are best deferred to Prius or Corolla websites...or better yet, get yourself a "Big Wheel".


 

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this could be the dumbest question for you . gas can't direct inject -diesel you can't clean the exhaust what about a mix or new fuel that can be direct inject run less compression than diesel to stay away from soot ? or something like that
 

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There are many engines that are direct gasoline injection. Volkswagen, Audi, chevy, and Jaguar use DI, to name a few. Biggest issue with DI is that the intake valves build A LOT of carbon which can cause misfires and performance issues in as little as 15000 miles. Fords ecoboost is a prime example of carbon related issues. Google VW carbon buildup if you want to throw up. The reason for the carbon deposits is simple. The breather pcv system takes oil vapor from the crankcase and directs it into the intake manifold to be reburned. Normally fuel sprays onto the back of the intake valve and this fuel actually cleans the oily residue from the pcv. On a direct injection engine the oil deposits build up quickly and form a large blockage because the fuel is being sprayed into the cylinder instead of behind the valve.
 

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Personally I like having a V8 under the hood. Better more powerful motor that will last longer than a suffering six. That being said, the millage could certainly improve. Could Toyota not introduce some rear end gear ratio options? The trucks are geared ridiculously low for the average guy that doesn't tow often. I'd rather have a 3:10 rear end so I could get 800kms out of a tank on the highway. Not that far fetched for a modern truck. My 2008 Ford E 350 extended van full of tools gets better highway mileage than my Tundra. Fact. I also had a 2011 Chev with an extended cab and 8 foot box,( same as my Tundra) that also did much better on fuel. It was a 5.3 with a 3:10 rear end.
 

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Personally I like having a V8 under the hood. Better more powerful motor that will last longer than a suffering six. That being said, the millage could certainly improve. Could Toyota not introduce some rear end gear ratio options? The trucks are geared ridiculously low for the average guy that doesn't tow often. I'd rather have a 3:10 rear end so I could get 800kms out of a tank on the highway. Not that far fetched for a modern truck. My 2008 Ford E 350 extended van full of tools gets better highway mileage than my Tundra. Fact. I also had a 2011 Chev with an extended cab and 8 foot box,( same as my Tundra) that also did much better on fuel. It was a 5.3 with a 3:10 rear end.
you can't compare the other trucks and the tundra by the rear end ratio only, there is a trans in front of it and that's where toyota is taller than the others. If they put a 3.10 or 3.21 with the current trans it would be stupid tall and be a dog loaded or towing and everyone would wonder what happened to the bad ass yota I force 350..

Top gear over-all ratio is about the same as the others, you can't get much lower than that with a gasser. The tundra rear end with the 10.5 ring and basically HD axle is just stout and loses efficiency due to the HD nature of it, although still not full floating. I think with only 6 gears, they got it the best it can be right now for ratios.

you can't have both, you either have a really stout rear end for a 1/2 ton and less MPG or lighter and smaller rear and better MPG.

toyota could gain some MPG by adding more gears though, not at the top gear overall ratio but by a new more efficiency and lighter trans with closer ratios in the mid gears and shorter up front to get the truck moving easier (for example, 1st gear in my truck is 4.71 (trans) x 3.92 (rear). They can also pick up some more efficiency in the motor with DI or the same treatment they gave the tacoma with the difference engine cycles.

Honestly, I drove a 3.21 Ram Hemi when I was shopping, and a 3.21 doesn't even belong in a truck, all it did was cuase them a nightmare when production got mess up and they had the wrong rear in trucks compared to the stickers, this is exactly why the toyota production system is the way it is, to avoid crap like that.

I grew up with toyotas and the old man was a national parts distribution manager and pretty much built the warehouse in aurora, il. He then specialized in lean manufacturing and distribution as a consultant when he retired from toyota. There is a reason toyotas are more reliable on the average, not having multiple rear ends and single option choices are all part of the toyota production system. You can't have your cake and eat it too I guess.

I would say, they need by 2017

projector headlights (the current ones suck and everyone on this site will attest to that).
push-button start on the plat and 1794
apple play on the top trims
8 speed trans like was just put on the lexus SUV
more HP and lbs with a tweak to the 5.7
storage of some sort
better drive info options (digital speed, and actual temps of trans and engine, etc). not just ave MPG, who cares...
LED turn signals and brake lights like everyone else has at least on the plat and 1794.

That would be a nice mid cycle refresh and I would ditch this Ram and have my 50K check waiting.....hear me toyota?
 

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Wait a minute!!!!!

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I would suggest Toyota engineers respond to fuel economy requests the same way I have. Ignore them and increase horsepower instead. :D

Individuals wanting fuel economy from full sized trucks are best deferred to Prius or Corolla websites...or better yet, get yourself a "Big Wheel".
S

You forgot the hand spin out brake!!!!!
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whats a km?
 

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I would suggest Toyota engineers respond to fuel economy requests the same way I have. Ignore them and increase horsepower instead. :D

Individuals wanting fuel economy from full sized trucks are best deferred to Prius or Corolla websites...or better yet, get yourself a "Big Wheel".


But my Uncle's Ram 1500 4x4 gets 26mpg on the highway....nevermind it has an 8 speed automatic and I believe a 3.21 axle ratio LOL.

In the right conditions the Tundra will get 20mpg easily on the highway, but throw in a crosswind or headwind and forget it LOL. Economy varies so much due to driving conditions I gave up trying to figure out the actual fuel economy...too bad it has taken Toyota 10 years to put a real fuel tank in these trucks though....they learn slow obviously.
 
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