14.6 MPG - 2014 SR5 - After lift and tires....
- Thread starter tomasallan
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KVA
Member
G8RB8_12SR5
New member
I did lift, wheels and tires this week and still getting close to 18 about 1.5mpg drop. I did keep stock size but went load E and more aggressive than stock, went with lighter wheels but the tires are still way heavy and that was the only impact I saw so far and the ride and look are exceptional.
BlackWorksInc
New member
How many of you guys are compensating for your inaccurate speedometer/odometers due to tire changes?
For example, going from my P265/65R17 factory tires to LT285/70R17's that's a 6.6% reduction in accuracy (my speedometer reads slower than I am actually going) which affects your fuel calculations as well as your mileage on your odometer.
If you don't have a SpeedoHealer installed, you should be compensating for what ever percentage difference your set-up is vs. stock to get the most accurate mileage/calculations. You'll probably find your mileage isn't as bad as you thought.
For example, going from my P265/65R17 factory tires to LT285/70R17's that's a 6.6% reduction in accuracy (my speedometer reads slower than I am actually going) which affects your fuel calculations as well as your mileage on your odometer.
If you don't have a SpeedoHealer installed, you should be compensating for what ever percentage difference your set-up is vs. stock to get the most accurate mileage/calculations. You'll probably find your mileage isn't as bad as you thought.
wfo9
New member
Just another data point and a fact that I found a bit surprising.
My truck currently has 285 17 Goodyear DuraTrac tires on 17x8 Konig wheels, 3" OEM lift, Air dam removed, Full Skids, Baja Rack, Sliders... Like the truck and it seems extremely capable offroad.
I daily drive at sea level and avg ~16.9 taking it easy in 50/50 mix.
I recently took a long road trip to Colorado, NM.... I had the truck and rack loaded up and drove (70-80mph on the way there) MPG dropped to about 14.5 until I got into the mountains. I can usually get 17 doing 100% HWY @70-75.
I was thinking it would really go to crap as I started going over passes... but the mpg started to improve. Once up in the mountains I was getting over 16 again. I was mainly in 4th gear and even held it in 3rd at times. Seemed really counter intuitive that the mpg was improving in those conditions. Even when I was off-road in 4lo for hours at a time, I still had an avg over 16.
It seems the drop in wind resistance at higher altitudes makes a huge difference. As it did loading the rack at sea level. I also expected the truck to struggle more in the mountains, but it actually felt very adequate. The power loss was not near as much as I expected. At 13,600 it was doing better than me ;-)
My truck currently has 285 17 Goodyear DuraTrac tires on 17x8 Konig wheels, 3" OEM lift, Air dam removed, Full Skids, Baja Rack, Sliders... Like the truck and it seems extremely capable offroad.
I daily drive at sea level and avg ~16.9 taking it easy in 50/50 mix.
I recently took a long road trip to Colorado, NM.... I had the truck and rack loaded up and drove (70-80mph on the way there) MPG dropped to about 14.5 until I got into the mountains. I can usually get 17 doing 100% HWY @70-75.
I was thinking it would really go to crap as I started going over passes... but the mpg started to improve. Once up in the mountains I was getting over 16 again. I was mainly in 4th gear and even held it in 3rd at times. Seemed really counter intuitive that the mpg was improving in those conditions. Even when I was off-road in 4lo for hours at a time, I still had an avg over 16.
It seems the drop in wind resistance at higher altitudes makes a huge difference. As it did loading the rack at sea level. I also expected the truck to struggle more in the mountains, but it actually felt very adequate. The power loss was not near as much as I expected. At 13,600 it was doing better than me ;-)
1engineer
Moderator
Here is a post I did awhile back that might explain it: http://www.toyota-4runner.org/5th-gen-t4rs/133786-cold-air-horsepower.html
Miguelon
New member
I have tried my hardest to put extra weight, bigger tires (276/65/20 DuraTracs), decrease air flow with all kinds of stuff like Pelican Boxes and Hi Lift Jacks, Hell I even tried to mount my Hi Lift on the front approach of my bumper....AND I stomp on the gas pedal like I am trying to put my foot through the floor. No matter what I do, the gas reading never drops below 10.9. What am I doing wrong? I thought I could get down below 10 MPG, but nothing has worked. I suspect that Toyota wont let it drop below 10.9. Any suggestions? Has anyone ever seen 10.8?
wfo9
New member
Yea, atmospheric conditions impact HP potential dramatically, but it has much less impact on how much fuel it takes to produce a given amount of work/HP. Better VE would result in less pumping and friction loss, but I think its pretty minimal on a modern fuel injected motor.
My theory is that these trucks (especially after being lifted and modified) suffer from a horrible drag coefficient. Adding to that is the substantial rolling resistance of off-road tires.
I have not done the math, but the air density is directly related to drag. Cut it in half and you cut drag by the same. I think this i why my mpg jumped so much in the mountains.
It's not really worth worrying about. These things are barn doors going down the road no matter how you slice it. Motor changes or gearing won't help that much. Some type of dynamic lowering suspension would do wonders, but totally not worth even wasting time thinking much about it.
It is what it is. Not much for fuel economy.
eddie333
New member
MPG increased AFTER lift?
I am really enjoying this thread, and cannot figure out my own MPG confusion:
***Disclaimer on figures: I don't live near or rarely drive in city traffic. I also accelerate slowly and never accelerate hard to compensate for speed decrease when going up hills. I am by all accounts a hyper-miler (our other cars are a hybrid Camry and Plug-in Prius, where I average 48 and 56 mpg, respectively)
So,
I've had 265/70/17 Duratracs on for 20,000 miles now and on similar drives I average around 19.1.
I do a particular 400 mile drive every few weeks and took the 4Runner, and averaged 19.2 last week.
I just installed the Toytec Ultimate lift set to 3/2. I did the same 400 mile trip and averaged 21.6?!? All conditions/speeds were the same. I was amazed and blown away at this increase.
I heard everyone's MPG dropped after a lift, and I am confused why mine went up?
I am really enjoying this thread, and cannot figure out my own MPG confusion:
***Disclaimer on figures: I don't live near or rarely drive in city traffic. I also accelerate slowly and never accelerate hard to compensate for speed decrease when going up hills. I am by all accounts a hyper-miler (our other cars are a hybrid Camry and Plug-in Prius, where I average 48 and 56 mpg, respectively)
So,
I've had 265/70/17 Duratracs on for 20,000 miles now and on similar drives I average around 19.1.
I do a particular 400 mile drive every few weeks and took the 4Runner, and averaged 19.2 last week.
I just installed the Toytec Ultimate lift set to 3/2. I did the same 400 mile trip and averaged 21.6?!? All conditions/speeds were the same. I was amazed and blown away at this increase.
I heard everyone's MPG dropped after a lift, and I am confused why mine went up?
Jeremy556
New member
You probably had a tailwind.
tamerunner
New member
I have. Is pulling a 6x12 utility trailer on the highway and in a hurry to get home. I saw 9.8.
2014 Warthog
New member
Did you measure it using the tank as well? Would be interesting to see what the real MPG was.
I think it gets wildly inaccurate when it gets that low.I was on a weekend off-roading trip recently and took my mileage reading for JUST the trail running. Measured by tank I got about 9.5 MPG but the dash said 13.5. Under normal circumstances the dash on mine is about 0.5 lower than actual.
tamerunner
New member
Did you measure it using the tank as well? Would be interesting to see what the real MPG was.
I was on a weekend off-roading trip recently and took my mileage reading for JUST the trail running. Measured by tank I got about 9.5 MPG but the dash said 13.5. Under normal circumstances the dash on mine is about 0.5 lower than actual.
My dash reading has been like yours the whole time I have owned it, it's usually only about .5 off. I didn't check it manually. I didn't by the runner for towing so it doesn't matter to me how bad it gets.
Did you measure it using the tank as well? Would be interesting to see what the real MPG was.
I was on a weekend off-roading trip recently and took my mileage reading for JUST the trail running. Measured by tank I got about 9.5 MPG but the dash said 13.5. Under normal circumstances the dash on mine is about 0.5 lower than actual.
Interesting. I'm going to have to start measuring manually as my dash so far after two fill ups is saying 14mpg.
budsrunner
New member
I have the same truck, but with icons and full Budbuilt skids. I drive mostly freeway and a lot of trails in the vegas desert. on highway at 75-80 im getting 16mpg. around town its 15. I also checked my speedo and its off by 2mph. not a big deal to me.
Hippestguyever
New member
Entertaining
After reading this very entertaining thread I did have a question, is there a way to reset the car computer or adjust it to account for the 285s vs doing the calculations manually? After getting 285s, is there anything else besides the speedometer you need to recalibrate? [MENTION=66316]1engineer[/MENTION]?
After reading this very entertaining thread I did have a question, is there a way to reset the car computer or adjust it to account for the 285s vs doing the calculations manually? After getting 285s, is there anything else besides the speedometer you need to recalibrate? [MENTION=66316]1engineer[/MENTION]?
1engineer
Moderator
If you check right now with stock size you will probably find you are going a few mph slow at 70 mph. The 285's should put you just about equal with speedometer reading versus actual speed.
gerfunken
New member
The other thing to think about is that your speedometer & odometer are now roughly 5% off with the larger tires. Larger tires = larger circumference, which means that they travel further on a single rotation.
The fuel economy (based on the digital readout) shows that you travelled 100 miles (when you actually drove 105) and your fuel economy would show that you got 14.6MPG, based off the 100 mile reading on the odometer, not the 105 actual miles... but if you add that extra 5%, you're getting 15.3 MPG
The fuel economy (based on the digital readout) shows that you travelled 100 miles (when you actually drove 105) and your fuel economy would show that you got 14.6MPG, based off the 100 mile reading on the odometer, not the 105 actual miles... but if you add that extra 5%, you're getting 15.3 MPG
