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I have been procrastinating for three years on lifting, because I do not understand much about lifting. [That and I procrastinate a lot anywho]

The big hold up is my wife's ability to get in/out of our stock JK.
The distance from the ground to the seat in a JK is the same as a TJ with a 2 inch lift. Wish I had known that before I bought the JK. Adding height is going to make it more difficult for her.

Today, I saw a YouTube clip by Extreme Terrain that said
Larger tire - more clearance between ground and axle.
Higher body lift - more clearance between ground and the body, skid plates.

Considering that we will not do anything extreme, it seems that 33 tires would add 1.4 inches, given that the OEM 265/70R17 tires are 31.6. That would be adequate for our purposes. Would 33's not only raise the axle but the body and frame the same distance?

Have I got the facts right?

Two questions.

1) If I got 33 tires, say 255/80R17, would that require new rims?
2) What is the purpose of backspacing, positive or negative? Or put another way, would this be a concern to me?

Thanks
 

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Remember that a increase in tire size only gets half that in lift. The tire size increase is split between top and bottom of tire. The increase s overall diameter. Tires are never the size of the sidewall, check the manufactures web site for the true measured diameter of the tires you have and the ones you want. What width of tires do you want?
My wife is short and the best thing I have bought is a set of grabbars, mounted to the a-pillar. The soft handles just don't cut it.
https://grabarsusa.com/
 

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Have I got the facts right?

Two questions.

1) If I got 33 tires, say 255/80R17, would that require new rims?
2) What is the purpose of backspacing, positive or negative? Or put another way, would this be a concern to me?

Thanks
You are almost there... like was said above tires only give you half the change in height , so 33s from 30.5s will get you maybe 3/4" higher from street to seat.

Lift, no matter body or suspension, will change the street to seat height by amount of the lift- so a 2 " spring lift will give you a 2" higher street to seat increase, same for a body lift.

You can add tires and lift to get a total so if you did a 2" lift with 33s then you are looking at a 2 3/4" change in street to seat height(ride height) 2" lift plus 1/2 the delta in height 1.5/2.

You can run the 255.80 on stock rims but check with manufacturer specs, they have approved rim widths for their specific tires. Also measured tire sizes vary quite bit based on MFR and rim width

Backspacing is distance from the inside of the rim to the wheel mounting surface. Do you need to be concerned with it? If you change wheels and tires or just tires or just wheels...yes. Among other things for tire fitment it determines the clearance between the inside edge of the tire sidewall and suspension and body parts.
Practically speaking if you are looking at 255/80-17s on stock wheels you should be good on the street and moderate wheeling
 

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I'm about a month ahead of where you are now. I too debated about how high to make our JK that still allows the Mrs. easy ingress/egress. I put on a set of KM2 255/80/17 on stock wheels recently and got about an inch more ground to third member clearance. Tire measurements need to be clarified as to if the weight of the vehicle is on them or unmounted, so keep that in mind when comparing heights. I haven't wheeled it yet since the new tires, but did a full flex test on a rock at my place and am just starting to make contact with the inner fender well in the rear. The contact is very light and was at full flex so I don't anticipate much of an issue during my normal moderate wheeling, i.e. Fins N Things at Moab for example. Having said that, I just ordered a Rancho 2" lift that I'll be installing this coming weekend so up she goes. Hoping the Mrs. won't notice the extra height!
 
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Discussion Starter #5
OK, there are dozens of lift kits available. Is there any consensus on the brands that are "best". ie your top 3 for 2 or 2.5 inch lift.
 

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I have a jks 2.5" lift on my JKU. I really like the spring rate, fairly stiff but not over the top. I have 35x12.5 tires.
One thing to consider is your alignment. Most companies say you don't need to worry about it with a 2.5 lift. My Jeep drove "okay" even with a wide tire. I bought some control arm drop brackets and it made a significant difference. The brackets were cheap and my plan is adjustable control arms, but that is a decision in itself.
Because I live in Canada there are some brands that don't have a distribution network and prices can be all over the map. JKS has a dealer close by for me.
I am running adjustable track bars front and rear, JKS also. Not needed but my ocd kicks in when I see a axle not centered.
 

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I’m very pleased with the Rancho 2” Sport lift. No drama, just shocks, springs and if needed, bump stops. I netted 2.5” front & 2.25” rear, with very little caster change and it drives great. There are multiple options out there regarding geo brackets or LCA, but I’m glad I took many folks advice to drive it first, then decide what, if any additional parts are needed. In my case, nothing else was needed and I left the bump stops off (but did drill the coil perch for in the future) which let the 255/80/17 M/T flex nicely without contact. I looked real close at the Teraflex 2.5, but it required new rims and might have lifted it a tad bit too high for the Mrs., so I went with the Rancho.
 

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My wife is also "height challenged" so she really liked it when I installed Poison Spyder Ricochet Rockers on our 4" lifted TJ in place of the plain tube rockers that were on it. The grab bars on the down tubes of our full cage also helped her.
 

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The big hold up is my wife's ability to get in/out of our stock JK.
The distance from the ground to the seat in a JK is the same as a TJ with a 2 inch lift. Wish I had known that before I bought the JK. Adding height is going to make it more difficult for her.
This is true, but on a TJ what I call the side board (the side on the Jeep under the door) is much taller so you have to really swing your leg up higher to get in on a TJ. The JK is much more car like as far as the side board goes. I'm 6'4" and an old fat man with bad back problems which really screw up my mobility. So getting in and out of normal human vehicles has always been a problem.

TJ side view



JK side view



I found those hand holds that attach to the windshield frame to be life savers both getting in and out. They should of put these in all Jeeps as standard equipment. You want these. Very rugged and easy to install.



I have seen these in action. A member here has them on his JK. RSE builds them. I can't speak of reliability on them so maybe if he sees this he'll speak up. They are no good for me as I'm so tall I'd have to really duck down to get my head in.

 

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And all that business of not having a real Jeep unless you have a huge lift is nonsense. You can get that aluminum armor for the underside and run some clearance fenders like Metal Cloak sells and run 35" tires on your stock suspension through some pretty good trails with no issues. IMHO the stock JK suspension is a lot nicer than the stock TJ suspension. I always worried about my stock control arms getting bent up on the LJ but not so much on the JK.
 

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Today, I saw a YouTube clip by Extreme Terrain that said
Larger tire - more clearance between ground and axle.
Higher body lift - more clearance between ground and the body, skid plates.

Considering that we will not do anything extreme, it seems that 33 tires would add 1.4 inches, given that the OEM 265/70R17 tires are 31.6. That would be adequate for our purposes. Would 33's not only raise the axle but the body and frame the same distance?

Have I got the facts right?

Two questions.

1) If I got 33 tires, say 255/80R17, would that require new rims?
2) What is the purpose of backspacing, positive or negative? Or put another way, would this be a concern to me?

Thanks
The 255/80 is a narrow tire but I'd think you could run them on stock wheels. I like wide off road tires myself like the 12:50/33 or 305. But they would just about surely require either new wheels with less back space or wheel spacers. I think the stock wheels are 5" back space wheels. For a 12:50 or 305 33" tall tire you'll want 3.5"-4" back spacing.

The stock Rubicon tire is about 32" tall so a 33" tall tire will only add 1/2" to the height of the Jeep. The height of the Jeep goes up by the difference in radius of the tire not the diameter.

Another tire option you may want to investigate is the BFG KO2 10:50/34/17 This is a nice riding tire that I believe fits on a stock JK.
 

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I have the AEV DualSport suspension and enjoy how it rides. They offer 2.5", 3.5", and 4.5" lifts.
 

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Hey John, it took me a while to see the irregularity, but in another post you were quoted and a link was added to your quote. Took care of it. That action cut ties to your above interaction.
 

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They are persistent
 

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Thanks Norm. Yes they are Don - I had a feeling that guy was a spammer. I looked at his IPs and there were six or eight different ones, usually a clear sign. Lately they put up an image of a head shot of a person.
 
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