What am I missing about offset?

[ChiTom]

Hi everyone, first post here.

I just got my 2019 Sahara and I'm looking to put some new wheels and tires on it. I've been looking all over this forum and there's a ton of great info posted, but there's still one thing I don't understand. I'm shopping for 20" wheels, and it seems like almost all of them come with negative offsets of around -25 or -18. I've seen a few 0 offsets, but that's pretty rare. The wheel and tire calculators (this one http://www.rimsntires.com/specspro.jsp seems to be the most comprehensive) I've found online seem to suggest that any wheel with about a +25 offset or lower would clear the suspension. If that's the case, why don't any wheels like that seem to exist? I'd prefer for my new wheels/tires to stick out from the jeep a bit more than stock, but not the full 3.5" I'd get on something with a -25 offset. What am I missing?

I've attached an image of the calculator showing that a +25 offset on a 35" tire would have the same clearance as the stock Sahara wheel/tires.

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[Shots]

My stock Sahara tires are 255/70/18. This is with the optional rims, but the tire size should be the same even if the treads not.

So to get the same clearance as the stock tires, you'd need a +10 rim, or a narrower tire.

 

[Arterius2]

My stock Sahara tires are 255/70/18. This is with the optional rims, but the tire size should be the same even if the treads not.

So to get the same clearance as the stock tires, you'd need a +10 rim, or a narrower tire.

Dude, no.

 

[mwilk012]

Just stop shopping for 20" wheels, unless you're putting on 40's.

 

[ChiTom]

My stock Sahara tires are 255/70/18. This is with the optional rims, but the tire size should be the same even if the treads not.

So to get the same clearance as the stock tires, you'd need a +10 rim, or a narrower tire.

Hah I can't believe I made such a simple mistake! This clears up the whole thing - thanks!

 

[mwilk012]

Hah I can't believe I made such a simple mistake! This clears up the whole thing - thanks!

That statement doesn't even make sense. How does that clear anything up?

 

[Dkretden]

OP, you are not missing anything. But, I am utterly confused by why you think that the post you responded to helped you.

If you want to put on a wider tire and you don’t want the wheels to stick out too far, you will need to adjust offset as you said. If you want to be sure that you will clear your suspension, use a tire calculator (I use this one....https://tiresize.com/wheel-offset-calculator/), vary offset and put the inner sidewall in about the same location as your current inner sidewall.

Those “BIG NEGATIVE” offsets are for the guys who want those outer sidewalls to be out 3” from stock.

Finding a rim at a zero offset or a +10 or +20 can be found...... but you also need to like it......

 

[mwilk012]

OP, you are not missing anything. But, I am utterly confused by why you think that the post you responded to helped you.

If you want to put on a wider tire and you don’t want the wheels to stick out too far, you will need to adjust offset as you said. If you want to be sure that you will clear your suspension, use a tire calculator (I use this one....https://tiresize.com/wheel-offset-calculator/), vary offset and put the inner sidewall in about the same location as your current inner sidewall.

Those “BIG NEGATIVE” offsets are for the guys who want those outer sidewalls to be out 3” from stock.

Finding a rim at a zero offset or a +10 or +20 can be found...... but you also need to like it......

I doubt it can be found in a 20” wheel, as those are made for the “Florida Man”.

 

[ChiTom]

OP, you are not missing anything. But, I am utterly confused by why you think that the post you responded to helped you.

If you want to put on a wider tire and you don’t want the wheels to stick out too far, you will need to adjust offset as you said. If you want to be sure that you will clear your suspension, use a tire calculator (I use this one....https://tiresize.com/wheel-offset-calculator/), vary offset and put the inner sidewall in about the same location as your current inner sidewall.

Those “BIG NEGATIVE” offsets are for the guys who want those outer sidewalls to be out 3” from stock.

Finding a rim at a zero offset or a +10 or +20 can be found...... but you also need to like it......

Thanks that's helpful too, I'll definitely keep shopping and hopefully I can find one. The other post was helpful though because it made me realize I was using the wrong stock tire size in the calculator - so pretty much everything I was plugging in looked like it was sticking out 4" farther!

 

[mwilk012]

Thanks that's helpful too, I'll definitely keep shopping and hopefully I can find one. The other post was helpful though because it made me realize I was using the wrong stock tire size in the calculator - so pretty much everything I was plugging in looked like it was sticking out 4" farther!

What size were you using before?

Edit: I see now, yes, that will make it quite a bit wider.

 

[lightsout]

The Stock is +44, on my Sahara I installed 18" x 9.5" wheels with 35"x12.5" KO2's, The 1st set of wheels I had were +10 offsett which is a 5.75" backspace, that was with a 2" spacer lift. I was not happy with the spacer lift so I installed the Rancho 3.5" spring and shock lift, however when you go to the higher lifts with more flexing they recommend you have a -18 offset (4.5" backspace). It worked out for me as the original +10 XD wheels had a warranty issue so I was able to swap out to Fuel Assault wheels at 4.75" backspace to accommodate the lift. My point is keep the future in mind especially if you plan to lift and go 12.5" tires. I know some will say just use spacers, the problem with that is many tire shops will NOT work on rigs that use spacers.

Below is with 4.75 backspace

Here is a 5.71 backspace

 

[Shots]

EDITED 4/14/19 at 1944 hrs to remove unnecessary response


To clarify my initial post.

I corrected the stock tire size, and then adjusted the new rim offset to make the suspension clearance "the same" while leaving everything else unchanged.
Here's an image of the same calculator used by the OP, with the numbers I replied with.

I'm not saying it's a look I would like or recommend. All I was saying was that to keep the suspension clearance "the same" (per the calculator) while using the desired tire size posted by the OP, it would need to be +10 offset rim to match that of the stock configuration.

 

[Dkretden]

For starters the OP did use a calculator, and posted an image of it. The concern posted was about keeping suspension clearance the same (as circled by the OP).
I corrected the stock tire size, and then adjusted the new rim offset to make the suspension clearance "the same" while leaving everything else unchanged.
So tell me exactly where I went wrong? Here's an image of the exact same calculator used by the OP, with the numbers I replied with.

I'm not saying it's a look I would like or recommend. All I was saying was that to keep the suspension clearance "the same" (per the calculator) while using the desired tire size posted, it would need to be +10 offset rim to match that of the stock configuration.
So you guys can say "dud no" or that it was unhelpful all you want, but the math works.

No need to get all defensive. I, and others, read your post and given how you wrote it, did not understand it. Apparently the OP did understand, so, great. Perhaps I have reading comprehension issues. Perhaps the other two people commenting on your post also don’t comprehend well either. I don’t know. It could also be that you didn’t write the 1st post well. I didn’t understand until the OP explained to me what your post was saying.

Doesn’t matter, the OP has been helped. And, helping the OP was the important thing.

G’day.

 

[FedeF]

I am a Floridian Man myself and got me 20”x9” with 275/60R20. Rim’s offset is +30 and the inside face of the tire is pretty much where the stock was. A lot of people put wider tires on stock rims (+44 offset) and go up to 295 tires with no problem. If you play with the tire size calculator, you will see that with a +30 you can go to 305 with no problem and possibly 315 before you have issues.
Off course the tire diameter also plays its part that needs to be considered!

 

[Shots]

No need to get all defensive. I, and others, read your post and given how you wrote it, did not understand it. Apparently the OP did understand, so, great. Perhaps I have reading comprehension issues. Perhaps the other two people commenting on your post also don’t comprehend well either. I don’t know. It could also be that you didn’t write the 1st post well. I didn’t understand until the OP explained to me what your post was saying.

Doesn’t matter, the OP has been helped. And, helping the OP was the important thing.

G’day.

Agreed. Maybe I could have articulated it better, maybe not. Doesn't matter, you're right. The important part is the OP got the help they were looking for. I edited my last response to remove the unnecessary defensive reply.

Cheers.

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