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I installed the old man emu medium duty kit , rocky road 1/4 in front spacers, and toyo open country 265/70/17 tires.

Jeep Commander Old Man Emu lifts are about 1.5-2" in lift height. How much lift do my tires give me?

I'm loving the setup so far, but I have one problem.

I forgot to measure the height before all my modifications and i want to know exactly how much height i gained.Can someone out there with an 07 5.7 hemi limited edition commander tell me their stock height? I'm measuring from the ground to the lip of the fender flare.
 

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From my observation, it seems as the front strut/shock, strut mounts and spring pads wear, the front suspension lowers or drops a bit. I did NOT measure before replacing those things, and perhaps its the Blistien 4600. But my Commander (V6) seem to have a bit more forward rake with the front suspension "appearing" to be lower after 100k miles from new. New Strut/Shock, Strut Mounts and Spring Pads and the front was raised right up after the job to be level, but over a few days it settled out to the forward rake again, but NOT as bad as before, it seems to be holding at my impression of what it was when it was new.

The lift the bigger tires add is simply 1/2 the difference of the diameter between old and new tires.

OEM Tires were P245/65-R17 which should be 29.54" in diameter. (I think all Commanders came with this tire size OEM, I might be wrong)

Your tires are P265/70-R17 should be 31.61" in diameter.

(29.54"-31.61")/2=1.04" increase in ground clearance by the tire alone.

Keep in mind, the tire sizes are for the carcass/structure/frame of the tire, deriving the overall dimensions from those sizes will just produce approximate numbers that vary slightly from brand to brand and even model to model within a brand. But it should be close. The tire pressure will effect its overall height as well for obvious reasons.

Safe to say, unless you're running your tires "aired" down, you got 1" of lift in the ground clearance.
 

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For those that don't know:
P245/65-R17

P=Passenger
LT=Light Truck
245 is the cross section width of the tire in millimeters (the cross section is the tire at its widest point, somewhere up the side wall, NOT the tread width).
You can convert MM to Inches by dividing by 25.4
65 is the Aspect Ratio in %, meaning the sidewall is this % of the cross section width.
R=Radial Tire
17 equal the rim width in inches, yep its mixed metric and standard in the tire size.

How wide are the tires (remember at its widest point, likely on the sidewall NOT the tread):
245mm wide tire/25.4=9.65"
265mm wide tire/25.4=10.43"

How tall are the tires sidewalls
9.65"*65%=6.27"
10.43"*70%=7.30"

The overall diameter of the tire (multiply the sidewall height by 2, since there is a sidewall on either side of the tire)
(6.27"*2)+17=29.54"
(7.30"*2)+17=31.60"

BUT, since only difference you care about, since the wheels are the same diameter, is the height of the sidewall under the wheel.
7.30"-6.27"=1.03"

Ideally, meaning actual tires will vary slightly, the difference between the OEM tire and your bigger tire is the height of the sidewall under the wheel, which the bigger tire has approximately 1" higher sidewall.

**Any difference between these figures and above, would be rounding errors as I go through the steps.
 

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The easiest way to determine what the lift has added to the height is to measure from the center of the wheel to the fender flare lip. That way you know what the lift added without having to worry about tire sizes and differences in tire makes etc. I don't know what the measurement is for a stock Commander but I think I read it somewhere on a post on this site.

Dan
 

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The easiest way to determine what the lift has added to the height is to measure from the center of the wheel to the fender flare lip. That way you know what the lift added without having to worry about tire sizes and differences in tire makes etc. I don't know what the measurement is for a stock Commander but I think I read it somewhere on a post on this site.

Dan
Yep, you can swap out any size wheel/tire, and that distance between lip and center of the wheel will NOT change. So its a good measurement for comparison, since it removes any difference bigger tires will make.
 
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