Upgraded from 265s to 275s. lost acceleration and mpg
- Thread starter Johncmng
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What tire and size? 275/70 r17, 285/75 r17? LT or P? Brand and model?
How are you measuring/ calculating mpg?
Gear swap is fed and rear differentials.
Good luck
rightyouareken
New member
Weight might be playing a factor too. What specific tires/size/load rating did you get?
Jetboy
New member
Typical gear swaps means removing both front and rear axle differentials and changing the gear ratios so that a revolution of the drive shaft to each differential results in less rotation of the wheels.
The only gear ratios available are what you have now - 3.73. And then there exists 3.91 from the Lexus GX and then the gears available jumps to 4.56. 4.56 gears would match with 39" tires. You've gone from 31.6" tires to about 32.1" tires. It's unlikely that gearing for about 39" tires would help your mileage.
I would start by making sure your tire pressures are correct. With LT rated tires - you should be running around 40-45psi. That may help some. But also they are heavier and higher rolling resistance.
The only gear ratios available are what you have now - 3.73. And then there exists 3.91 from the Lexus GX and then the gears available jumps to 4.56. 4.56 gears would match with 39" tires. You've gone from 31.6" tires to about 32.1" tires. It's unlikely that gearing for about 39" tires would help your mileage.
I would start by making sure your tire pressures are correct. With LT rated tires - you should be running around 40-45psi. That may help some. But also they are heavier and higher rolling resistance.
I'm assuming this is going to be a stock road oriented tire (like the Dunlops) over to something much more aggressive and heavy (maybe C-rated Falken AT3Ws)?
Some of the MPG loss is almost certainly related to weight and tread pattern, not the tire size alone. Even if you swap from the stock OEM highway tires over to a more aggressive C or E load 265/70R17, you're probably going to see your MPG go down by around 1 at minimum.
Some of the MPG loss is almost certainly related to weight and tread pattern, not the tire size alone. Even if you swap from the stock OEM highway tires over to a more aggressive C or E load 265/70R17, you're probably going to see your MPG go down by around 1 at minimum.
delloro
New member
Nope. That's why new cars usually come with lame tires. Long wear, low rolling resistance.
blackened_offroad
New member
now you need a supercharger and a gearing change. the cycle continues.
patkelly4370
New member
I run 285s and avg mid 17 mpg.
I have a 12 mile, 6% grade to go up and down to get to work.
Sent from my SM-G955U using Tapatalk
I have a 12 mile, 6% grade to go up and down to get to work.
Sent from my SM-G955U using Tapatalk
DallasTRDPro
Member
Get a Pedal Commander. Sprint Booster. HikeIt.
mcat707
Member
This right here ^^^
Gotta pay to play.
Re gearing is a costly upgrade. Be prepared to put out some coin.
I run 285/70/17 Falken Wildpeak MT’s. Heavy ass tires. I average 15mpg
16 on a good day.
Jono.ful
New member
So you added 15lbs or so to each corner, and increased the surface area and rolling resistance, but you're surprised that the engine needs to burn more dino juice to do the same speed on the highway than it did before the new rubber?
Takes all sorts I suppose...
Re-gear will cost you about $3 - 4k in parts and labour
btw, the sun is bright. Don't stare at it too long....
Takes all sorts I suppose...
Re-gear will cost you about $3 - 4k in parts and labour
btw, the sun is bright. Don't stare at it too long....
TRD PANTHER
New member
When I went from the factory 265's to 275 KO2's in a E load I lost about 1.5 to 2 miles per gallon. The E load 275 weighs a hefty 58 lbs. as I recall, and that is the major reason for the loss of acceleration and gas mileage. I went to 285/70-17 Falken AT3W's in a Standard Load (SL) with a weight of 51 lbs. each. My gas mileage improved by .5 to 1mpg over the 275's.
Acceleration seems to fine in all conditions with the 285's. I drive 5 miles to work by street and go through an elevation change of 1400 feet up and down. I consistently get 15-15.5 mpg doing this. I use to get 14.5-15mpg with the 275's. I would not waste money on a gear change. The 275's actually put the speedometer right on the money and the 285's are only 1mph off.
michalik.piotr6837
New member
Jono..... lmfao. No shit.
Dinosaur Overland
New member
anomalous
New member
Lost 1MPG going from Nitto Terra Grappler 265\70\17 SL load @ 40lbs each to Toyo Open Country RT in 285\70\17 E load @ 60lbs each. Definitely can feel the sluggishness of the bigger\heavier tires even with the supercharger, but all this was to be expected. The supercharger definitely helps, and it can still go if I need it to. I feel like it's not that I can't get the lost mpg back with the bigger tires, but that it's more sensitive. I have to drive really conservatively to gain back the lost in efficiency, easier on highway\freeway speeds. Once I hit city traffic, the MPG drops quick. All in all, I think for me the benefits of going to larger tires out weigh the negatives
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Finslayer83
New member
3" toytec alumas
285's - e load
sliders - 100lbs
LFD "wide" skid - 75lbs
Warn bumper/winch - 144lbs
Average 17.3 mpg via trip and 17.1 via fuelly/manual calc.
TN hills and 50/50 driving.
285's - e load
sliders - 100lbs
LFD "wide" skid - 75lbs
Warn bumper/winch - 144lbs
Average 17.3 mpg via trip and 17.1 via fuelly/manual calc.
TN hills and 50/50 driving.
