MPG on your 3rd Gen?

What difference does overdrive and fuel type make?
I’ve heard leaving overdrive off puts less strain on the transmission at lower speeds then switch on at about 50mph is more fuel efficient,
I’ve also heard to leave it on all the time unless towing.
Also will using a higher grade fuel be more efficient or vice versa?
Just wanting to optimise my fuel consumption seeing the dramatic increase in our fuel prices here. This is also my first automatic and I’ve only had it for a short time so not particularly familiar with all the little details.
I have a RZN185 and running 91 I get about 15mpg in a hilly town 30-50mph mostly.
Am a little heavy on the throttle though
 
What difference does overdrive and fuel type make?
I’ve heard leaving overdrive off puts less strain on the transmission at lower speeds then switch on at about 50mph is more fuel efficient,
I’ve also heard to leave it on all the time unless towing.
Also will using a higher grade fuel be more efficient or vice versa?
Just wanting to optimise my fuel consumption seeing the dramatic increase in our fuel prices here. This is also my first automatic and I’ve only had it for a short time so not particularly familiar with all the little details.
I have a RZN185 and running 91 I get about 15mpg in a hilly town 30-50mph mostly.
Am a little heavy on the throttle though
Unless you are supercharged and need to run a higher octane, there really isn’t much of a point in running any higher octane than 87. You might see a slight increase in fuel economy (less than 1 mpg), but your cost per mile for gas will be higher with higher octane. Ethanol free FHA’s will increase your fuel economy, but again your cost per mile will be higher.

Turning overdrive off prevents your transmission from shifting to 4th and allows for torque converter lockup in 3rd which will keep the transmission cooler while driving up inclines. I didn’t notice any increase in fuel economy by using overdrive off until I hit 45-50. Some people have reported getting better fuel economy by leaving it in ect power mode.

Edit: this is my experience with a 5vz/auto/4wd with no armor, no lift, 265/70R17ks, and stock 4.30 gears.
 
I filled up last night and got 22.3mpg for my work commute. It’s 25 miles and 36 red lights at 4:30am and my drive home is 29 miles on rural roads with 12 red lights or stop signs.


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What difference does overdrive and fuel type make?
I’ve heard leaving overdrive off puts less strain on the transmission at lower speeds then switch on at about 50mph is more fuel efficient,
I’ve also heard to leave it on all the time unless towing.
Also will using a higher grade fuel be more efficient or vice versa?
Just wanting to optimise my fuel consumption seeing the dramatic increase in our fuel prices here. This is also my first automatic and I’ve only had it for a short time so not particularly familiar with all the little details.
I have a RZN185 and running 91 I get about 15mpg in a hilly town 30-50mph mostly.
Am a little heavy on the throttle though

O/D will not magically increase your fuel efficiency. At best it will be maintained, but more likely it will drop. If it worked like that then automakers would advise you to turn it on when needed, not turn it off. Literally half the point of overdrive is to provide better fuel economy than the car would've otherwise.
Both the 3RZ and 5VZ were designed to run on 87 octane with 0% ethanol (or whatever 87 is for you guys, I know Europeans measure octane differently) so aside from removing the ethanol content there's not much benefit you'll see; certainly nothing that will offset the cost. Unless you're supercharged there is very little reason to go for 91 octane, one must remember these engines are non-interfering and high compression was never considered in their development.
Still, I've said it once and I'll say it 100 times again: ethanol free makes all the difference if you can find it. EVERY time I fill up with E10 I find myself refueling 1-2, maybe 3 days before I normally would.
Edit: Weird, I could've sworn I read your location as like Iceland or something, not NZ.
 
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Still, I've said it once and I'll say it 100 times again: ethanol free makes all the difference if you can find it. EVERY time I fill up with E10 I find myself refueling 1-2, maybe 3 days before I normally would.

I did the ethanol free test in my little Saturn and had the same mpg and was out an extra dollar per gallon.

I’ve noticed a difference running mid grade. (1 to 2 mpg) but now most places are pricing 89 octane at 10c less than high test. Not worth the 80 cents to get 1 more mpg.


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Unless you are supercharged and need to run a higher octane, there really isn’t much of a point in running any higher octane than 87. You might see a slight increase in fuel economy (less than 1 mpg), but your cost per mile for gas will be higher with higher octane. Ethanol free FHA’s will increase your fuel economy, but again your cost per mile will be higher.

Turning overdrive off prevents your transmission from shifting to 4th and allows for torque converter lockup in 3rd which will keep the transmission cooler while driving up inclines. I didn’t notice any increase in fuel economy by using overdrive off until I hit 45-50. Some people have reported getting better fuel economy by leaving it in ect power mode.

Edit: this is my experience with a 5vz/auto/4wd with no armor, no lift, 265/70R17ks, and stock 4.30 gears.

O/D will not magically increase your fuel efficiency. At best it will be maintained, but more likely it will drop. If it worked like that then automakers would advise you to turn it on when needed, not turn it off. Literally half the point of overdrive is to provide better fuel economy than the car would've otherwise.
Both the 3RZ and 5VZ were designed to run on 87 octane with 0% ethanol (or whatever 87 is for you guys, I know Europeans measure octane differently) so aside from removing the ethanol content there's not much benefit you'll see; certainly nothing that will offset the cost. Unless you're supercharged there is very little reason to go for 91 octane, one must remember these engines are non-interfering and high compression was never considered in their development.
Still, I've said it once and I'll say it 100 times again: ethanol free makes all the difference if you can find it. EVERY time I fill up with E10 I find myself refueling 1-2, maybe 3 days before I normally would.

So leave overdrive on unless it’s struggles up a hill and towing?
91 is the lowest octane we can run in NZ, but it is ethanol free.
I’ll have to try with ect on then, normally I only switch it on before overtaking.
Thanks for the help guys
 
So leave overdrive on unless it’s struggles up a hill and towing?
91 is the lowest octane we can run in NZ, but it is ethanol free.
I’ll have to try with ect on then, normally I only switch it on before overtaking.
Thanks for the help guys


That’s what I do in the states. I tried locking out overdrive and noticed nothing.

Achieving the speed to get the torque converter to lock up is the best method to get better mpg. For my 97 with 4.10 gears it’s 48mph with overdrive enabled or 40-42mph if it’s disabled.


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That’s what I do in the states. I tried locking out overdrive and noticed nothing.

Achieving the speed to get the torque converter to lock up is the best method to get better mpg. For my 97 with 4.10 gears it’s 48mph with overdrive enabled or 40-42mph if it’s disabled.


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Ok, as I say this is my first automatic so how do I know if the torque converter is locked up?
 
Ok, as I say this is my first automatic so how do I know if the torque converter is locked up?
When the torque converter locks up it will have an rpm drop similar to another shift. With the torque converter locked when you increase throttle you shouldn’t see a jump in rpm like you would if you were in 1/2/3 gear.
 
This old girl can only muster 16 yet I do drive it pretty hard and turn off OD a lot on hill climbs, 3400 rpm is not near as efficient as 2100 at 70mph...
 
Ok, as I say this is my first automatic so how do I know if the torque converter is locked up?

If you have a 5VZ-FE engine with an A340 4-speed automatic transmission (this may differ as you name is 'hiluxsurf' after all) it will lock up under normal driving at 50 MPH under light cruising speed. If you go heavy on the throttle it will unlock.

Count the number of shifts when driving from a full stop. The first shift is 1-2, the second is 2-3, the third is 3-4 and the fourth shift is not a shift at all but the torque converter locking up to lower RPM when cruising.

To continue the conversation on ethanol free, a few years back there was a noticeable 1 MPG drop in my fuel charting when California added ethanol. It most definitely decreases mileage as there's less energy in a gallon of ethanol than in a gallon of gasoline so the more ethanol in the fuel, the lower the gas mileage.

To add to the high octane debate, it might actually be economical now to run 91 octane if you can acheive better gas mileage. I did this on my old 91 and gained just a hair over 1 MPG more over 87 octane. It was not economical however as the price of gas was around $3 and was $3.40 for 91 octane, or an increase in 13% in price. Now with 87 octane at $6 and 91 octane at $6.40, that's only a 7% increase in price. Gaining 1 MPG from say, 16 to 17 is also about a 7% increase in mileage. Make cents?
 
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Today I got 23.7 MPG (3rz 5 spd) on the highway. I was carrying a bunch of stuff too, cruise control set to 73. Stock tires, no important mods. The only other time I got 23 was on the highway, and I was going 80 a lot of the time. Maybe I got ethanol free gas, but the pump didn't mention anything.

Normally I get 18 city, 22 highway. I rarely get over 300 miles on a tank, but that is more because I don't like having the needle that close to empty.
 
If you have a 5VZ-FE engine with an A340 4-speed automatic transmission (this may differ as you name is 'hiluxsurf' after all) it will lock up under normal driving at 50 MPH under light cruising speed. If you go heavy on the throttle it will unlock.

Count the number of shifts when driving from a full stop. The first shift is 1-2, the second is 2-3, the third is 3-4 and the fourth shift is not a shift at all but the torque converter locking up to lower RPM when cruising.

To continue the conversation on ethanol free, a few years back there was a noticeable 1 MPG drop in my fuel charting when California added ethanol. It most definitely decreases mileage as there's less energy in a gallon of ethanol than in a gallon of gasoline so the more ethanol in the fuel, the lower the gas mileage.

To add to the high octane debate, it might actually be economical now to run 91 octane if you can acheive better gas mileage. I did this on my old 91 and gained just a hair over 1 MPG more over 87 octane. It was not economical however as the price of gas was around $3 and was $3.40 for 91 octane, or an increase in 13% in price. Now with 87 octane at $6 and 91 octane at $6.40, that's only a 7% increase in price. Gaining 1 MPG from say, 16 to 17 is also about a 7% increase in mileage. Make cents?


It’s interesting you only have a 40 cent spread between 87 and 91-94 octane. In my area is around a dollar and some places have the mid grade 10-20cents lower than high test.


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I average 19-20 total. V6 5-speed, 1.5" lift with mild AT tires that are slightly bigger than stock. The best I got was 20.8 mostly on the highway, after I cut a 3" hole in the airbox. Still need to run through a few tanks to see if that made a difference in fuel economy, or if I just had good luck driving with the wind.
 
If you have a 5VZ-FE engine with an A340 4-speed automatic transmission (this may differ as you name is 'hiluxsurf' after all) it will lock up under normal driving at 50 MPH under light cruising speed. If you go heavy on the throttle it will unlock.

Count the number of shifts when driving from a full stop. The first shift is 1-2, the second is 2-3, the third is 3-4 and the fourth shift is not a shift at all but the torque converter locking up to lower RPM when cruising.

To continue the conversation on ethanol free, a few years back there was a noticeable 1 MPG drop in my fuel charting when California added ethanol. It most definitely decreases mileage as there's less energy in a gallon of ethanol than in a gallon of gasoline so the more ethanol in the fuel, the lower the gas mileage.

To add to the high octane debate, it might actually be economical now to run 91 octane if you can acheive better gas mileage. I did this on my old 91 and gained just a hair over 1 MPG more over 87 octane. It was not economical however as the price of gas was around $3 and was $3.40 for 91 octane, or an increase in 13% in price. Now with 87 octane at $6 and 91 octane at $6.40, that's only a 7% increase in price. Gaining 1 MPG from say, 16 to 17 is also about a 7% increase in mileage. Make cents?

That explanation is great thank you.
The only fuel here that has ethanol I believe is 98, but our lowest octane is 91 about $2.99 and 95 is about $3.13 I’m not sure on the exact difference in mileage seeing I only tried 95 once so far but there definitely wasn’t a noticeable change. Which I didn’t think was worth the extra cost.
Although I may try it again and try working it out properly like you have.
But wow I thought our fuel prices were bad with the exchange rate our 91 is equivalent to $1.87 usd.
Your paying equivalent to my $10 a litre.

Edit, apparently USA and Canada 91 are not the same as everywhere else 91 and also you guys use gallons not litres so the maths is wrong. Your fuel is 2/3rds the price of ours
 
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That explanation is great thank you.
The only fuel here that has ethanol I believe is 98, but our lowest octane is 91 about $2.99 and 95 is about $3.13 I’m not sure on the exact difference in mileage seeing I only tried 95 once so far but there definitely wasn’t a noticeable change. Which I didn’t think was worth the extra cost.
Although I may try it again and try working it out properly like you have.
But wow I thought our fuel prices were bad with the exchange rate our 91 is equivalent to $1.87 usd.
Your paying equivalent to my $10 a litre.
The US and Canada rate octane differently than the rest of the world - keep that in mind. Whenever a North American person is talking about (R+M)/2, not RON.

American vs European fuels – Octane rating – eTuners

-Charlie
 
-

The 4th gen 4runner V8 was designed to tow 7000 lbs with a hitch that attaches to the chassis and can support a weight distribution hitch system. You could see if that hitch will bolt up to the 5th gen chassis, supposedly the chassis was similar.
 

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