What’s the Real MPG of Lexus GX470? Our investigation

We've always been wondering why a lot of car manufacturers lie so hard about gas mileage in their cars. This is one of the most important factors for us when we are choosing a car and usually, we get frustrated when we count up how much money we actually spend on fuel each month. Because these figures don't match with what we expect.

The MPG of the Lexus GX470 is not expected to be very low. Actually, we even expect it to be much higher than average.

But what about the official gas mileage? And what about the real figures that people show after they have some experience with this vehicle? We decided to have a close look.

And here's what we are going to tell you:

1. Manufacturer's claimed MPG of the Lexus GX470.
2. Actual gas mileage that you will probably see in the city and on the highway.
3. How to reduce the gas mileage in your Lexus?
4. What can make the Lexus GX470 mileage much better?

Let's get started!

What does Lexus say about the mileage of the GX470?

We wouldn't say that Lexus is or was a company that worried much about fuel consumption and about the economy of its clients. They have always been thinking about luxury vehicles that provide their buyers with wonderful comfort and the freshest technologies. But fuel economy has never been the first priority.

And too bad, because the GX470 was equipped with the only one engine type - the 4.7-liter V8 engine with an archaic 5-speed automatic transmission (now it's archaic, though it was not so bad in 2002). This combination is not about the economy.

So, the gas mileage (official) for the Lexus GX470 is as follows:

• city- 15.4 miles per gallon or 15.3 liter per 100 km;
• highway- 20.6 mpg or 11.4 l/100 km;
• combined- 16.8 mpg or 14 l/100 km.

We wouldn't say it's too bad for the V8 and for the 2002 luxury SUV. But if you compare it with some of its counterparts, you will see that Lexus is just very thirsty for fuel. It drinks up all gas from your tank much sooner than you have a possibility to buy some more gas on the highway. And sometimes it can be a problem.

But let's dig deeper and find some information in different forums and reviews. How much fuel does the Lexus GX470 actually burn? We bet the real consumption is higher than the official figures want us to believe.

Real-life consumption of the Lexus GX470

In the real life, this vehicle will take much more fuel than you expect. Why? Because it has the V8 engine offering you 235 to 263 horsepower depending on the year (pre-facelift and post-facelift). And you are not likely to drive this car like an old granny would drive her Ford Fiesta. You are going to press that pedal harder, right?

And what will you expect to see? Let's look at some reviews:

• people say that active driving in the city will raise the fuel consumption much and it will be around 12 mpg or even worse;
• then, we've read some reviews of people who tried to drive these SUVs really fast - over 120 mph, and they registered 10 mpg gas mileage;
• on average, owners get about 14 mpg in the city and 18 mpg on the highway with relatively calm driving;
• once you start stepping hard on that gas pedal, you just see how the fuel level arrow moves down;
• it's not hard to see that these vehicles are not made for the economy if you read some reviews of people who hate their Lexuses for being so gas-thirsty;
• also, people say that they rarely see on their dashboards figures of consumption that are promised by Lexus.

You can see that the GX470 is the vehicle that is going to take a lot of money out of your pocket. Especially now, when the gas prices are going up. Many Lexus owners say that it's time to buy something not so big and more economical because they have already understood that driving the GX is not that great both in terms of the 'coolness' of the vehicle and in terms of expenses.

So, the GX470 will not be the best vehicle if you want to economize some money on fuel. But thanks to its big-displacement engine, it's actually durable and non-problematic. Here's our article on the longevity of these vehicles.

Why does my Lexus GX470 take so much fuel?

If your Lexus shows poor gas mileage (something like 10 mpg in the city), you should check some things before you actually go to the gas pump. We know some reasons why a Lexus can start drinking up gas like crazy.

First of all, check if you have any "tuning" in your ECU. Only original Lexus settings are OK for the best fuel consumption. You can tune the GX470 engine, but it will only give you more power, not good consumption.

Here are the main things that will also affect gas mileage in your Lexus:

1. Oxygen sensors. Your Lexus GX470 has some catalytic converters and each comes with an oxygen sensor. Once it's broken, it sends mad signals to the ECU and the ECU changes the air-fuel mixture settings. This may lead to a 20-30% deterioration of gas mileage.
2. Injectors. This is a simple engine in terms of technologies and it has relatively simple and also durable injectors. But when the mileage is high, they can clog and affect your gas mileage. Sometimes, the drop in the mileage will be around 10% or even more.
3. Catalytic converters. The converters may clog at 100,000 miles or a little later. You should replace them. Buy a new original converter or a decent aftermarket option and replace the clogged converter to get back your normal gas mileage in a big Lexus vehicle.
4. Malfunctioning spark plugs and ignition coils. These are the parts we would check at first. They are relatively not expensive to replace, so if a bad ignition coil is in charge, it's not a big problem. Better replace old spark plugs every 50-60 thousand miles.
5. One or two cylinders not working. With a V8 engine, you can keep on driving even if 6 cylinders only work. One or two cylinders may have problems with compression. Your engine will lose power in this case, and it will also shake when idling. Unfortunately, if this is the case, you will have to pay a lot for the repair.
6. Transmission problems. The 5-speed automatic transmission in the GX470 is not the best option for fuel economy. And when it malfunctions and shifts at the wrong time, the gas mileage may get 10-15% worse.
7. Dirty air filter. Well, it can only take up to 5% of your gas mileage, but it will create a lot of problems. For example, it may be the main sponsor of your clogged injectors.
8. Bad tires or tire pressure. A GX470 is a big and heavy car. If you have bad wheel alignment in your SUV or your tires have the wrong pressure, the engine will try hard to push the vehicle and will burn much more fuel. Check these factors before you do anything else.

We can keep on telling you about the MAF sensor, throttle body, and all other things that can influence your fuel consumption in the vehicle. But those 8 points are the most popular for the GX470. And we know that if you check all of them, you will definitely find the reason for the very high fuel consumption and poor gas mileage in your vehicle.

How to drive the Lexus GX470 to get better gas mileage?

Are you still not glad about the amount of gas your Lexus burns when you drive it? Let's look at some tips that you can use to reduce fuel consumption without doing anything with your car.

Here are some ideas:

• warm the engine because these engines will work efficiently when they are in an optimal working temperature;
• use premium gas - any other gas will not have optimal octane level and your Lexus will not be as efficient as it can be;
• don't press on the gas pedal with all power you have - be careful and drive like a person who has just got a driving license;
• keep your speed at 55 mph on the highway - this is the most economical way to drive your Lexus.

But if your car shows around 14 mpg in the city and 20 mpg on the highway, you should know that you are a lucky Lexus owner, the engine works properly and you shouldn't even try to make the mileage any better.

Final words

We love the Lexus GX470, but we know that this was a good car from 2002 to 2009. Now, it's quite old and it burns too much fuel. If you have enough money to buy a lot of gas, then why not consider this vehicle as a luxury alternative to a budget car that you can buy for the same money? This is a very reliable and basically problem-free vehicle. You should just put up with these scary consumption figures on your dashboard.