2" vs 3" Lift MPG

[dheeter]

With gas at $4 a gallon and not looking like it is going down, I cannot decide what size lift and tires I want. This will be a hard question to answer, but I am hoping to get as many responses as possible, with as much info as possible.

What is the difference in gas milage between a 2" spacer lift with 32" tires and a 3" spacer lift with 33" tires?

Additional Info: The tires are Toyo Mud Terrains, the 32's are 63 lb. and the 33's are 66 lb. With the 2" lift I will get 17" wheels and with the 3" lift I will get 18" wheels. So I figure about 5-10 lb. more per tire/wheel. For consistancy purposes please just give the MPG reading from the 4runner's computer. Also MPG before and after the lift would be very helpful.

Thank you very much in advance, I'm hoping this will turn up some good results to help myself as well as other T4R owners in deciding which lift is the most practical.

 

[03_4x4Runner]

I lost 2 MPG going to a 2.5" Daystar lift and BFG all terrain 265/70/17 tires. This mileage was figures with a GPS as the odometer to eliminate the speedometer error with larger tires(2.5 mph at 70 mph difference with taller tires). I never pay to much attention the the computer mpg as it is usually optomistic 2 mpg unless recently resett. Mine is a 2003 V8 and i used to be able to get almost 20 mpg on the highway. I am lucky to get 18 now on the highway. Also a slight power lose and longer braking distances. i would imagine 33" tires would be even worse.

 

[T?@\7]

with 3" ome and 33" tires my little MPG computer reads on average 18.3-18.5 (which I know isnt exactly correct.)

 

[boston_kevin]

Don't forget the difference between your current tires and the new ones you are considering. You are looking at closer to 15+ lbs difference per tire than your current setup.

The higher you go, the more air you have to push as you go down the highway. This affects the MPG as much or more than then weight of the tires.

I am running BFG 265/70 17" wheels with no lift and I have not seen any appreciable difference in my MPG's in 6000 miles.

 

[jeremysoca]

with 3" ome and 33" tires my little MPG computer reads on average 18.3-18.5 (which I know isnt exactly correct.)

wow, how can that be. My computer is is pegged at 14.4. How much highway vs street?

 

[teampwr2]

If you plan on doing alot of 4 wheeling stay with a smaller rim 16" or 17" and use a taller profile tire ..reason being you want more rubber between the rocks and your rims ,if you use a larger rim size you lose the valuable rim clearance especially if you ever need to air down .
I have a 3" lift and use 265/75/16 BFg all terrain ko Just my 2 cents worth

As for milage it all depends on how you drive ....I drive like a granny and only go 60 -65 on the hiway and putt around town I always get 20 + mpg city or hiway and thats on the odometer not the toyota computer thing

 

[webe363]

i have a 3/2 lift with 265/70r17s. per the computer i get about 21-22 hwy, 19-21 city. so, no real loss in mpgs..which i am very happy about.

 

[Wolf]

I've got a body lift, a 3" spacer lift and 285s. I drove all over L.A. today and the guage only moved about 1/8th a tank. I'll try some accurate calculations this weekend and get back to you.

 

[T?@\7]

wow, how can that be. My computer is is pegged at 14.4. How much highway vs street?

im gonna say that is nearly all in town driving.

 

[boston_kevin]

T?@\7 - what have you calculated for the speedo/odom being off due to the tire size difference? I know the trip computers are normally 10% off, I would think with 33" tires you'd be looking at another 5-6% minimum.

 

[4Runnin_ToyBoy]

Just for my curiousity, can you just take your 4R into a dealer and have them reset the computer to accurately reflect the speed of the vehicle with the altered wheels/tires?

 

[AmbideXtrous]

Just for my curiousity, can you just take your 4R into a dealer and have them reset the computer to accurately reflect the speed of the vehicle with the altered wheels/tires?

I don't think it's that easy. Even though many things in the 4R are now computerized, the basic mechanism for reading the speed of the wheels is still mechanical. If it is all calibrated to a particular size tire/rim combo then when you change to significantly larger or smaller tires you throw off the whole geometry of the system.

 

[T?@\7]

T?@\7 - what have you calculated for the speedo/odom being off due to the tire size difference? I know the trip computers are normally 10% off, I would think with 33" tires you'd be looking at another 5-6% minimum.

BK- I havent personally calculated the difference due to the 285s, but im pretty sure ive read the info before over on toyota120.com , maybe ill go see if i can find it..... I seem to remember something like 3%. (**edit** "I have 285/70-R17 (33") MT/Rs the correction was +8%" this is from Alexjet on toy120, he has a v6 which I dont think matters)

And as far as the mileage, before the tires I averaged 23-24 (on the computer)

Im also pretty sure that the only way to have your speedo read correctly is to re-gear.

 

[dheeter]

Thanks for all the input. It looks like you gas milage depends mostly on how and where you drive. I know the smaller wheels are better for off roading, but I wont be doing anything to serious with my 4runner (I can just take my little brothers tacoma for that ). I will still take it in the mud, but for the most part its just for looks. As far as tire weight goes it has a much larger impact on gas milage for city driving, while the height of the car impacts freeway driving. My mpg computer says I get 21, and my calculations usually come out around 19 or 20. I just want to stay above 15 mpg (actual, not on the computer) which seems pretty likely. I am going to go with the 3/2 with 18" wheels and 33" tires, probably within a month. I will post some pics when its done. Thanks again.

 

[OneEyedHito]

Daystar 2.5 Kit

have about 300 miles or so on my Daystar 2.5 and I am showing 20.3 on the Console MPG Calculator......That has been mostly highway miles though in the last day. I was running consistently at 17.4 on the Comp through a few tanks before that so I am sure it will drop some.

BTW, tires are 70 Series.

Also, the kit looks great and I think the ride is excellent also, can't really say if I notice a difference with it at all, and didn't notice a wind difference on the highway.

Good Luck
1IH

 

[OneEyedHito]

I don't think it's that easy. Even though many things in the 4R are now computerized, the basic mechanism for reading the speed of the wheels is still mechanical. If it is all calibrated to a particular size tire/rim combo then when you change to significantly larger or smaller tires you throw off the whole geometry of the system. [/QUOT

FYI - The local Toyota Dealership referred me to a local Speedo Shop (Russ's Speedometer Shop - Sharonville OH) to have the calibration done.

long story short they can do it but it requires a "Converter" and Calibration that will run me $286.00 US!!!!

I am going to live with the 1-2mph at 55MPH difference and Dear Old Dad told me that the odometer issue is decimal points so............

 

[Wolf]

Thanks for all the input. It looks like you gas milage depends mostly on how and where you drive. I know the smaller wheels are better for off roading, but I wont be doing anything to serious with my 4runner (I can just take my little brothers tacoma for that ). I will still take it in the mud, but for the most part its just for looks. As far as tire weight goes it has a much larger impact on gas milage for city driving, while the height of the car impacts freeway driving. My mpg computer says I get 21, and my calculations usually come out around 19 or 20. I just want to stay above 15 mpg (actual, not on the computer) which seems pretty likely. I am going to go with the 3/2 with 18" wheels and 33" tires, probably within a month. I will post some pics when its done. Thanks again.

looking for 18" black wheels? pm me or search the posts for Procomps. Thanks

 

[ProMed]

The higher you go, the more air you have to push as you go down the highway. This affects the MPG as much or more than then weight of the tires.

I drove with the 3" OME lift and the stock tires for several months and had no change at all in the mpg during that time. However as soon as I put the 275 Cooper STTs on it dropped a consistent 20-30 miles less per tank corrected.

 

[boston_kevin]

I drove with the 3" OME lift and the stock tires for several months and had no change at all in the mpg during that time. However as soon as I put the 275 Cooper STTs on it dropped a consistent 20-30 miles less per tank corrected.

With the Jeeps, the higher you go, the more air you have to push... I haven't lifted mine 4runner yet, but I figured the aerodynamics were about the same. That's awesome that the lift didn't affect gas mileage. I would think on the highway the higher profile would be pushing more air (like having a cargo basket on the roof).

 

[Wolf]

My computer says I'm getting 17 mpg highway. Just drove it on a trip with a light load and 1 other passenger. I've got a body lift and spacer lift (around 4") and 285/65/18 Nitto T/Gs. It's probably getting a little better than that and was trying to remember the formula for figuring it out- something by setting the trip odometer between fill ups and change in revolutions/correction for larger tires....?