Has noting to do with "ford" or "toyota". One is turbo'd and the other is NA. Two totally different technologies pumping/sucking air into a ICE.
Toyota would be dominating in power if they put a Rotrex on the Tundra, or a turbo on tacoma or rav4 4cyl. FA engines don't last as long.

There's little to do to make a NA ICE be more fuel efficient, short of re-engineering the intake and exhaust systems, making the air pump more efficient.

 

The only way I can see the GX gain a few MPGs on the highway is by lowering it (lowering springs or coilovers) and adding air dams where needed undercarriage... but all of these go directly against the reasons why so many buy this SUV. Shedding weight will also help, like leaving the spare at home, etc.

 

I didn't want to go there, but yeah, to buy a GX and worry about MPG's, doesn't make much sense to me.

 

The 470 is considerably more aerodynamic than a 460, especially a 2014+ 460. The problem with the GX isn’t so much aerodynamics it’s lack of forward gears in the transmission, being under powered and weight. An 8spd or 10spd trans would help as would cylinder deactivation. The latter not being something that’s as robust for Toyota’s liking. Too bad because a combo of an 8spd and cylinder deactivation pushed my two HEMI Chargers 35-40 mpg on the highway depending on elevation change frequencies. I can only imagine what shedding a few hundred lbs and adding an 8spd trans would do to the fuel economy. But too little too late. A hybrid is Toyota’s only legit hope to get the GX up in to averaging mpg in the 20’s. In the real world a turbo V6 just won’t cut it.

 

I agree about the 8-10 speed transmission. Spreading out the gears would help tremendously. The drag coefficient is a lost cause for the GX. I've just accepted I was going to pay the "ultimate reliability tax" from day one. Haha.

 

Toyota could blow the doors off of all its competition, if they would import the GX & LX with their bulletproof twin turbo V-6 diesel. I would buy one in a heartbeat! So far, GM’s in-line 6 Duramax diesel is the one to beat. You can get a Suburban, Yukon or even an Escalade that gets mid twenties (mpg)!

 

The cylinder deactivation stuff ruins the motors. At least it did for for the fleet of Tahoes I used to oversee. They were all cop cars that idle a lot and every single one of them had issues. It got so bad that we went in and deactivated the ‘feature’ - solved the problem. Spending extra to save on fuel but ruining the long term reliability of the motor is not a win. Ford ruined the 5.0 with their efficiency stuff too - have 20 or so of them now and they all burn oil. It is a shame.

 

... as is the auto-turn-off feature designed to save fuel at stop lights. Assuming the lingering oil film is exactly the same as having constant oil pressure ... don't think so ... and then there is the additional starter wear-and-tear. Now here's an idea ... let's eliminate the 10% ethanol from gasoline and gain a 3-4% improvement in MPG. Ethanol-Free gasoline is available in select locations ... https://www.pure-gas.org/

 

What about the Chrysler hemi? They had a cylinder deactivation system & I never heard about the same problems as GM vehicles.

 

Hah, reliability tax. That’s a great way to put it.

That’s why I said it isn’t something Toyota would do. I will say the ones I had in my last three HEMI’s were great.

It’s not a common problem. I never had issues in the three vehicles with 5.7’s that had it. I only have good things to say about what it did for my fuel economy.

 

Not sure, never bought them for cruisers. The highway patrols use them because they are inexpensive and run 150 or so. I prefer the Tahoe or F150 because they are large and safe. The deactivation causes issues with the lifters and the cams. You’ll spend far more fixing them than you’ll sped on fuel.

 

So the OP asked about how THE EXISTING can be improved from an MPG standpoint. Don't know how this post spiraled off into alternative engines. How is this information in any way helpful ?

 

We drifted off by discussing how other manufacturers are getting more mpg out of their competing SUVs. It’s all good as I’ve learned a few things.

 

Did stray but still on topic of fuel economy and I learned a few things. Worthy thread

 

And I have added “reliability tax” to the daily vocabulary for the GX world haha!