About LC Gas Efficiency

[Marinna]

We just did an interesting experiment today on my LC FE with KO3 for gas efficiency and it give us a very interesting insight about the car.

First I am a pretty light driver, I would consider myself 3/10 with 10 is the heaviest. On interstate I mostly stay within posted speed about 5 miles (so on a 65 my average would be 60-65) and I use a lot of cruise control. My partner is, however, very heavy and I would describe as 8/10. She usually take 10 over posted speed as minimal and spend around 25% of the miles beyond 80 MPG.

I am the driver most of the time. I average around 20 MPG on the new KO3 with about 45 psi on hot wheels.

Today we are driving on a section of pretty hilly road on I-5 for 150 miles. The elevation on first half mostly is around 4000 ft and the second half would drop from 4000 ft to 500 ft. I had my partner drive this section today. I initially expect about 10-20% less MPG given we are sinking down to the sea level in the last 70 miles.

And what surprised me is that we end up at 14.7 MPG for what I would usually get 21+ MPG coasting down from the mountain. So this is a sharp -30+% efficiency drop just from how you drive.

I hope this experiment can give people some insights. It is not scientific so don’t be overly serious about it

 

[rjmh]

We see a difference in drivers I our household as well. Thankfully not as large, but my wife is consistently about 10mph faster than me on the highway and I get about 10% better economy.

 

[Marinna]

We see a difference in drivers I our household as well. Thankfully not as large, but my wife is consistently about 10mph faster than me on the highway and I get about 10% better economy.

All hybrid power chain and turbo are sensitive to load, speed, and acceleration from the driver.

I remember my partner complained to me that the hybrid battery on my Prius Prime breaks when she drive at 90+ mph. I just told her she is looking a quick way to heaven driving a car made by plastics and carbon fiber at that speed…

So my conclusion now is if you drive LC with an all-terrain at 80-90 mph you get a V8 level gas consumption.

 

[Impatient]

I have noticed a massive difference in fuel efficiency, for the worse, when I get within touching distance of 80. Around 55-60 I’m 25 mpg. Around 78-82, I’m 16 mpg.

 

[Area 51]

We just did an interesting experiment today on my LC FE with KO3 for gas efficiency and it give us a very interesting insight about the car.

First I am a pretty light driver, I would consider myself 3/10 with 10 is the heaviest. On interstate I mostly stay within posted speed about 5 miles (so on a 65 my average would be 60-65) and I use a lot of cruise control. My partner is, however, very heavy and I would describe as 8/10. She usually take 10 over posted speed as minimal and spend around 25% of the miles beyond 80 MPG.

I am the driver most of the time. I average around 20 MPG on the new KO3 with about 45 psi on hot wheels.

Today we are driving on a section of pretty hilly road on I-5 for 150 miles. The elevation on first half mostly is around 4000 ft and the second half would drop from 4000 ft to 500 ft. I had my partner drive this section today. I initially expect about 10-20% less MPG given we are sinking down to the sea level in the last 70 miles.

And what surprised me is that we end up at 14.7 MPG for what I would usually get 21+ MPG coasting down from the mountain. So this is a sharp -30+% efficiency drop just from how you drive.

I hope this experiment can give people some insights. It is not scientific so don’t be overly serious about it

No new news here "And what surprised me is that we end up at 14.7 MPG for what I would usually get 21+ MPG coasting down from the mountain. So this is a sharp -30+% efficiency drop just from how you drive."
I see this sort of response in all my diesel trucks, not the same numbers necessarily but the same delta mileage ranges every time i do the same sort of exercise.

 

[TakaraLC]

This is common with turbo engines. When fully engaged, turbo generates roughly 1 atm pressure. Making the 2.4L displacement volume effectively 4.8L when fully boosted. So depending on how a person drives, a fuel efficiency will similar to an engine with 2.4L to 4.8L displacement volume.

 

[ultane]

All hybrid power chain and turbo are sensitive to load, speed, and acceleration from the driver.

… and wind speed and direction.. especially for our ‘brick shaped’ chariots.

 

[TakaraLC]

… and wind speed and direction.. especially for our ‘brick shaped’ chariots.

Plus full time 4WD.

 

[Marinna]

I have noticed a massive difference in fuel efficiency, for the worse, when I get within touching distance of 80. Around 55-60 I’m 25 mpg. Around 78-82, I’m 16 mpg.

That is my conclusion as well. You get the best efficiency at 55-60 mph, it will start to drop beyond 60 and beyond 65 or 70 you will see the cliff.

 

[DeepDive]

I like going fast as much as the next person, but I don't see this as the one I'm doing 90 in!

I do think that if Toyota was going hybrid on these, they could have found a way to boost fuel economy, but they clearly were going for some increase in economy, but a greater focus on torque. I swapped out the Michelin 265/70/R18's for Nitto Terra Grappler 275/70/R18's. Went from an average 21mpg down to 19mpg. Not horrible, but since the Nitto's aren't much heavier and are still SL rated tires, they aren't that far off the OEM's. Doesn't feel like I should see that much of a decrease, but that's where it currently stands. I'm running them at 40psi and will be trying 35psi this week. Don't think going down will improve mpg though.

Selling the Michelins on another thread if anyone is interested.

 

[jayce]

Wind resistance increases with the square of the speed FWIW.

So 60 mph ^2 =3600 units
80 mph ^2 =6400 units

Bound to have a pretty significant effect on mpg.

 

[J44]

So just did a trip first half of drive my speed was between 53mph -60mph, for about 70 miles, snow on roads, second half trip 70mph-74mph, highway drive, clear roads for about 70 miles as well. KO3’s running about 44-46 psi. Whole trip 20.63mpg. I don’t think that’s to bad. I did stop to car wash and get salt and sand off but left LC running. Tires 265/70/18, and trip was on pretty flat roads, minor up and down. Gas 91 octane, not sure that makes any difference.

 

[edecurtis]

I’m running 275/65/18 @ 35psi and I’m lucky to get 17MPG and 277 MTE should I increase the psi to 45? I feel like I’m driving an EV with this range.

 

[Marinna]

I’m running 275/65/18 @ 35psi and I’m lucky to get 17MPG and 277 MTE should I increase the psi to 45? I feel like I’m driving an EV with this range.

40+ psi is specific to e-rated tire (I am using KO3). Although I admit I don’t know what is the correct pressure for KO3 and on the manufacturer’s website they did not provide any instruction neither.

I think your problem is probably caused by the size. I never do that, never know any benefit doing that. My original sharing was more about the effect of driving behavior to gas mileage not the effect of tire size. Perhaps you can do a similar report on the effect of tire pressure on your 275.

 

[jnsplace]

If I do my driving on mostly flat land, i'm in 19ish. If I do my driving home/work which has a lot of hills; I'm down to about 17 - 18. Heavy brick indeed!

 

[edecurtis]

40+ psi is specific to e-rated tire (I am using KO3). Although I admit I don’t know what is the correct pressure for KO3 and on the manufacturer’s website they did not provide any instruction neither.

I think your problem is probably caused by the size. I never do that, never know any benefit doing that. My original sharing was more about the effect of driving behavior to gas mileage not the effect of tire size. Perhaps you can do a similar report on the effect of tire pressure on your 275.

Yeah I have KO3 too. My LC came with 245/60/18 and it looked stupid. I have been looking for the correct PSI settings see if I can get better MPG. Also, there is no way to recalibrate the speedometer either.

 

[misnMy4runner]

Rolling on 275/60r20 AT3s and can’t get past 17mpg. Only other modification so far are the 2 factory skid plates that replaced the tin underbody protection. I am a bit worried that with the additional CBI rock sliders on the way it’ll only get worse. It’s one of the disappointments I have with the LC thus far.

 

[StickerFab]

We see a difference in drivers I our household as well. Thankfully not as large, but my wife is consistently about 10mph faster than me on the highway and I get about 10% better economy.

My wife will always be the largest (not physical size also) variable when it comes to fuel economy. She seems to have a heavy foot that she abruptly drops on the skinny pedal. Also seems to believe the brake and throttle are on off switches. Doesn't coast very much. She'd fight me if she saw this though.

 

[Greasecar1]

1958 with 265/70/R18 KO3s. I get 19 to 19.5 usually, in eco, on pavement. Got about 22.5 with the Yokohamas (although I only did one tank with those). I'm no expert, but is it possible that we might see a slight improvement in the summer, due to hybrid battery temps? I'm wondering. I ran that first tank with the Yokos, and then it got cold about the time I put on the KO3s.

 

[Bigfoot]

Driving style and speed absolutely affect fuel economy, along with a score of other factors including how it is calculated. in general the turbo boost gauge is a good indication of real-time economy. I try to keep off of boost as much as possible but still only get 19+ mpg on most tanks. (Heavy LT265/70R18 KO3 tires on stock 1958 rims at 36 psi.)

I have seen a drop of roughly one mpg with colder temperatures. A unique feature of the LC is how the engine shuts down when load is low and it switches to the electric motor. I have coasted down highways for miles with engine rpm at zero which produces crazy high mpg readings. Then up the other side economy drops like a rock. Don't ask about towing.