so how do I calculate my gas mileage now that im lifted?

[yellowssm]

i know i could just divide my miles on a tank but doesnt the mileage im putting on my car read a little off now? The tires I upgraded to are 265/70/18 vs the stock 265/60/18 which are over 2" taller.

 

[Dkon82]

I believe the those types of readings are measured through your transmission, so no matter what type of lift or tire size you go with, all readings remain accurate. Not 100% sure though.

 

[MikeInNH]

Adding larger or smaller tires WILL effect how to calculate the gas mileage.

Years ago to compensate for this you'd replace the gear where the OD cable connected to the tranny. But it's a completely different setup now.

Your speedometer will also be effected. You'll actually be traveling faster then what the reading is. It's dependent on how much larger the tires are.

 

[ClockWork]

I believe the those types of readings are measured through your transmission, so no matter what type of lift or tire size you go with, all readings remain accurate. Not 100% sure though.

Nope - wrong. You must take the new tire circumference into account.

 

[yellowssm]

ok so how do we calculate it? I used to get around 300-315 on a tank and it looks like Im gonna get around 280ish (still on the original tank after the lift and tires)

 

[ClockWork]

ok so how do we calculate it? I used to get around 300-315 on a tank and it looks like Im gonna get around 280ish (still on the original tank after the lift and tires)

C'mon let's think about it here. You need to find the % difference in circumference between your old and new tires.

It isn't brain surgery.

 

[yellowssm]

C'mon let's think about it here. You need to find the % difference in circumference between your old and new tires.

It isn't brain surgery.

How does the circumference help you figure it out? Wouldnt the speedometer % be the difference? Doesnt the speedo calculate the miles?

Either way here are the circumferences, speedo %, diameter differences

265/60/18 vs 265/70/18

circumference
95.84 - 102.4

diameter
30.51 - 32.60

speedometer difference
6.849%

 

[MikeInNH]

How tall were the OEM tires you replaced...And how tall are the new tires.

If the old tires were 30" tall...and the new tires are now 33" tall..that's an increase of 10%...

So you'll be traveling 10% faster then what's actually being displayed..and you'll have traveled 10% farther then the OD reading.

If you're traveling at 40mph...you're actually traveling at 44mph.

If you OD says you traveled 300 miles...you actually traveled 330 miles.

What size tires did you original have???

 

[yellowssm]

How tall were the OEM tires you replaced...And how tall are the new tires.

If the old tires were 30" tall...and the new tires are now 33" tall..that's an increase of 10%...

So you'll be traveling 10% faster then what's actually being displayed..and you'll have traveled 10% farther then the OD reading.

If you're traveling at 40mph...you're actually traveling at 44mph.

If you OD says you traveled 300 miles...you actually traveled 330 miles.

What size tires did you original have???

265/60/18 vs 265/70/18

circumference
95.84 - 102.4

diameter
30.51 - 32.60

speedometer difference
6.849%

ok I got it. easy to calculate now. just add the 6.849% thanks