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Old 09-06-2019, 12:36 PM
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Tire Question

Want to replace stock wheels and tires. 2010 Jeep Wrangler Sahara Unlimited with 25570R18. Do not want to lift yet. He is 16. But want to go as tall and wide as I can get WITHOUT modifications for now. I think stock wheel is 9"(?) If I replace wheels and tires what is largest I can go and not modify? Slight extension from wheel well OK but not much. Thanks

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Old 09-06-2019, 01:08 PM   #2
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There are several issues to consider. The first is the gearing in the differentials. Most likely you have 3.21s, possibly 3.73s if you have certain packages. Probably the first thing you want to do is download the build sheet for the Jeep. It can be done here:
https://fcacommunity.force.com/RAM/s/equipment-listing

(I just tried it on my TJ and it works. It says it for the RAM, but works for all CDJRs)

Second keep in mind that increasing the height of the tires will increase the fuel mileage a bit based on the differential gearing. Get to high for the gears and it will go down not up. Increasing the width of a tire will always decrease the fuel mileage because of the additional rolling resistance of the wider tires.

You can probably get by increasing the tire height 1" without a lift or regearing. That will put the top of the tire 1/2" closer to the fender and raise the Jeep 1/2". You can probably get by increasing the width by a bit. For example, the stock tires are P255/70R18s which are 32" tall and 10" wide. Going to LT275/70R18s will give you a 33" tire that is 10.8" wide. They may rub a bit in full lock steering but you can just avoid the full lock turning most of the time.

Part of the issue with the Sahara tires is that they are just plain tires. You might consider going with a more aggressive tire in the stock size. I had the stock Sahara tires on my '15 Sahara and they were just blah. My '17 Chief came with the very aggressive BFG KM tires (no longer made) but you can get the BFG KO2s to fit your 18" wheels for $252 (before mounting, etc) or save $6 a tire by putting on new wheels. You can get the Goodyear Duratracs to fit the 18" wheels for $212 (again before mounting, etc) or get the 17" for $27 less.

If you are not in love with the factory wheels, then you can replace them with 17" and get a much better tire selection. Quadratec has page after page of wheels that will fit the JKU. They are also a Wrangler Forum supporter and offer WF members a discount. If you find a wheel that appeals to you, call them (they actually have customer service that answers the phone) explain you are a WF member and ask for a quote on the wheels.

I have their wheels on my TJ and was very impressed with the quality of the wheel and the packaging of the wheels. I have stored my original silver wheels in those same boxes in case I ever want to go back to silver (instead of the black) wheels.

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Old 09-06-2019, 01:16 PM   #3
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Originally Posted by coachgjohnson View Post
Want to replace stock wheels and tires. 2010 Jeep Wrangler Sahara Unlimited with 25570R18. Do not want to lift yet. He is 16. But want to go as tall and wide as I can get WITHOUT modifications for now. I think stock wheel is 9"(?) If I replace wheels and tires what is largest I can go and not modify? Slight extension from wheel well OK but not much. Thanks
As mentioned, knowing where you are starting from is good advice.
There is a sticky thread that answers this question at great length
https://www.wranglerforum.com/f27/la...er-142837.html
Bigger tires will make your Jeep slower, and your fuel mileage will be worse. It will look better, but performance and fuel mileage will suffer.
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Old 09-06-2019, 01:53 PM   #4
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Quote:
Originally Posted by coachgjohnson View Post
Want to replace stock wheels and tires. 2010 Jeep Wrangler Sahara Unlimited with 25570R18. Do not want to lift yet. He is 16. But want to go as tall and wide as I can get WITHOUT modifications for now. I think stock wheel is 9"(?) If I replace wheels and tires what is largest I can go and not modify? Slight extension from wheel well OK but not much. Thanks
I ran stock tires, rims and gears for 2 years before upgrading to 33's, since then have gone bigger with lift, gears. As you get to know your Jeep your Jeep will grow with you .
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Old 09-06-2019, 02:59 PM   #5
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Most people here run a 2.5 inch lift with 35x12.50 tires on a 17x9 inch wheel with 4.5 inches of backspacing. If you don't want to lift yet, I'd suggest the same wheel with a 33x12.50 tire or a 285/70-17 (33x11.50).
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Old 09-07-2019, 09:52 PM
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So it came with 18". You suggest going 17" with the new wheels?
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Old 09-08-2019, 04:21 PM   #7
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That's what I did. You just have a wider selection of wheels and tires in the 17 and 20 inch size than 18's.
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Old 09-08-2019, 05:31 PM   #8
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I have a 2010 Sahara 2 door. I put on 33x12.5x15s with no lift. The only thing I had to do was trim a small section of the corner off the plastic airdam as it would rub at full lock. I actually ended up just removing the thing.


I now have a 2.5" AEV DS lift and when these tires wear out will be going up to a 35x12.5x17
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Old 09-09-2019, 07:26 AM   #9
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I have a 2010 Sahara 2 door. I put on 33x12.5x15s with no lift.

While all 15" 5 on 5 steelies will fit, only a few alloy 15" 5 on 5 wheels will clear the brake calipers. The smallest factory wheels on a JK were 16" steel on the base Sport and 17" alloy on Sport S and Rubicons while the Sahara got 18" wheels (only the designers know why they went 18").
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Old 09-10-2019, 06:30 PM   #10
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While all 15" 5 on 5 steelies will fit, only a few alloy 15" 5 on 5 wheels will clear the brake calipers. The smallest factory wheels on a JK were 16" steel on the base Sport and 17" alloy on Sport S and Rubicons while the Sahara got 18" wheels (only the designers know why they went 18").
Yes, and I do have alloys. https://www.discounttiredirect.com/b...dx4-7s/p/77500


Photo is prior to lift

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Old 09-16-2019, 11:26 AM
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Thanks everyone for the advice. My son selected a 17 x 9 Ultra wheel and Dick Capek LT285/70R -17 tire. (33 inch?) Replacing stock 18 wheel with 265 (32 inch?) Tires. If I read correctly this will add a 1 inch height and they will fit with no modifications needed. On next Tue change he wants to do the lift and get more aggressive but now, just a better look and stance. These will fit with no problem? Thanks!
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Old 09-17-2019, 07:46 AM   #12
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Unless he is going off road with a lot of wheel drop, he shouldn't need a lift. The stock tires for the Sahara were 32", the LT285/70R17 tires are 32.7". That means there is less than 3/8" less clearance between the top of the tire and the fender, and the centers of the wheels are now about 3/8" higher off the pavement. Remember 1/2 of the increase of tire height is below the axle and 1/2 is above the axle.

The LT285s are however 1.2" wider (11.2" wide) than the 255s (10" wide) so the inside of the tire will be a little over 1/2" closer to all the suspension components. He may experience some rubbing in tight turns. If the new wheels have less backspace that the originals, there might not even be any significant rubbing.

That is the same size tire (considered a 33" tire) that comes on the JL/JLU Rubicon which has higher fenders and axles that are 2" wider (1" further out on both sides) than the Sport and Sahara (which still mount 32" class tires).

If that were my Jeep with those tires, I would not bother with a lift, and if the tire rub and resulting reduction in turn radius bothered me, I would just put spacers on all four corners.
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Old 09-18-2019, 10:30 AM
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I really appreciate all this good info. Certainly not a strong suit if mine. I learned nothing like this growing up, but my son sure as hell will even though I am learning as I go.
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Old 09-22-2019, 06:35 PM
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You guys are awesome. The 285s on 17s are PERFECT for what I wanted. Does not extend out past fenders, no scrubbing, no mods needed. What? Leveling? 17 year old drives it, so don't really want to lift it yet. Now she is "starting" to look like a Jeep!
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Old 09-27-2019, 03:04 PM
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One last question. On the LT285 on the 17" wheel what do you run for tire pressure? They shipped at 80psi. (Dick Cepek)

OEM 18inch 265 tires call for 35 psi. Don't mind rugged ride but keeping my teeth when hitting a bump is preferable 🙂
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Old 09-27-2019, 03:07 PM
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One last question. On the LT285 on the 17" wheel what do you run for tire pressure? They shipped at 80psi. (Dick Cepek)
OEM 18inch 265 tires call for 35 psi. Don't mind rugged ride but keeping my teeth when hitting a bump is preferable 🙂
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Old 09-27-2019, 04:01 PM   #17
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One last question. On the LT285 on the 17" wheel what do you run for tire pressure? They shipped at 80psi. (Dick Cepek)
OEM 18inch 265 tires call for 35 psi. Don't mind rugged ride but keeping my teeth when hitting a bump is preferable 🙂
Usually between 28 and 32 psi.
Lower pressures will ride better. Higher pressures will help with mileage and wear, but at the expense of ride quality.
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Old 10-19-2019, 10:43 PM   #18
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We need some advice please.
Our 2000 Wrangler Sport
has 33x12.50x15 tires on Mickey Thompson wheels which are 10" wide.
We want to downsize.
Will appreciate any suggestions .
Thanks
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Old 10-20-2019, 07:58 AM   #19
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You are mixing Wranger types. This discussion area is about the JK (2007-2018) but you are asking a question about a 2000 which is a TJ (1997-2006). You would be better off asking your question in the TJ General area.

Your 33x12.50R15 tires are actually about 32.5" tall. You can go down one size to 31x10.50R15 tires which are about 30.8" tall but you will have to go to new wheels as well or 30x9.50R15 tires which are about 29.5" tall (with again new wheels).

The reason you have to replace the wheels is the simple fact that you have 10" wide wheels and the smaller two tires will not safely mount in wheels that wide. Most likely you have a lift to acommodate the 33" tires, and the smaller tires won't look good with the lift.

Why do you want to change?
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Old 10-21-2019, 12:25 AM   #20
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You are mixing Wranger types. This discussion area is about the JK (2007-2018) but you are asking a question about a 2000 which is a TJ (1997-2006). You would be better off asking your question in the TJ General area.

Why do you want to change?
Thanks for your reply...didn't mean to poach on the JK forum. I thought I was in the TJ section.

We are seniors...we bought the TJ (which I knew what we have)…in June...to use as a toad. We like the TJ ..it needs tires, which we knew when we bought it and are simply thinking of going down a bit for convenience sake. Even tho we do not have any problems getting in and out of it.
The TJ has a 3" lift.

We spoke to a Tire fellow who we have done business with for many years...he recommended BF Goodrich 32x11.50R15 KO2
and said it would fit our wheel.

We are exploring our options and appreciate the knowledge this forum offers.

Thanks
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Old 11-11-2019, 04:36 PM   #21
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I have 2017 JK unlimited with 225/75R16 on standard steel rims. Can I upgrade to 245/75/R16 without any mods or worries?
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Old 11-11-2019, 09:31 PM   #22
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I just mounted 285/70R17 Duratracs to my '17 75th Anniversary model. I had to mount 1.5" spacers due to rubbing but have no problem with clearance without a lift. Around town it's fine but when I took it on the highway today it seemed like there was a lot of vibration. The tires were balanced and a 4 wheel alignment was done. Anyone know why it would be riding rough at highway speeds?
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Old 11-12-2019, 09:49 AM   #23
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Is it constant vibration or does it appear at a speed and then disappear. The larger a tire the harder they are to get balanced properly. Did they balance the tires with road force? The 31" (245/75R16 Duratracs on my TJ are fine all the way up to 75mph). If it is speed sensitive, it is definitely the tire/wheel, especially since it just appeared with new tires. Most of the time speed sensitive vibrations are in a 10mph range, typically 45-55, 50-60 are typical. If you have stick on weights, it could have had one come off, or even if you have clamp on weights they can come of. My tire dealer offers free balancing of tires they install for the life of the tires. They don't even bother to look mine up as they know they are the only place that I will let touch my tires (other than me as I do my own rotating). They also rotate for free, but in the time it takes me to drive there and back, I can have it done myself.

It could also be runout on tire. Not common but happens to all the manufacturers. That is when the tire is not perfectly round. Years ago I put LT 305/70R16 tires on a pickup. The truck was only a few days old (120 actual miles) and on the way back to work (it was done over lunch) at 35mph I could feel the vibration. Looking in the rear view mirror I could see the right rear corner of the truck going up and down.

I called back to the tire dealer and went back after work for them to re balance the tire. They then sent me to their main store the next day at lunch to road force balance the tire to no avail. When the tech manually rotated the tire on the balance machine you could see the wobble in the tire. They dismounted the tire and checked the runout on wheel - it was fine. They had to order me replacement tire which came in the next day.
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Old 11-12-2019, 08:06 PM   #24
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Admins please delete double post

You sure can. I ran 265/75R16 0n my '09 for 7 years with no issues at all.
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Old 11-12-2019, 08:09 PM   #25
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I have 2017 JK unlimited with 225/75R16 on standard steel rims. Can I upgrade to 245/75/R16 without any mods or worries?
Yes, you sure can I had 265/75R16 on mine with no issues.
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Old 11-13-2019, 03:15 AM   #26
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I have 2017 JK unlimited with 225/75R16 on standard steel rims. Can I upgrade to 245/75/R16 without any mods or worries?

The 225/75R16 tires are 30" tires (actually about 29.5" tall). The 245/75R16 tires are 31" tires (largest installed on a TJ) are are the stock tire for my TJ Rubicon. They are 30.5" tall and are still smaller than the stock tires on the Sahara and Rubicon JKs (32" tires).

The 265/75R16 tires are 31.6" tall, just a fraction shorter than the 32" tires. They are a bit wider and you may experience some rubbing at full lock. However, if this bothers your, you can adjust the max the wheels will turn.

If I had a JK/JKU with 16" wheels that is what I would consider. However, if you look in the local Craigs List, you may find some JK/JKU take offs that you can get for less than the cost of new tires, and they will come with the aluminum wheels. A set on 17" Rubicon wheels would be preferred, but a set on 18" Sahara wheels may be easier to find. The height of both those stock tires is right at 32" and will fit your Sport without mechanical modification. You will have to have the tire size in the computer flashed so your speedometer and odometer are more accurate what ever you do.

Note: Just a quick look at my local CL and found JL Sahara 18" wheels and tires (32") for $700 for 5 and a set of JL Sport S 17" wheels and tires (LT245/75R17 - 31.5") tires and wheels for $450. I doubt you can get 5 tires for that. Even if you don't really like the tires, the JL Sport S 17" wheels have a decent appearance.
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Old 11-15-2019, 08:22 AM   #27
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Yes, you sure can I had 265/75R16 on mine with no issues.
Thanks
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Old 11-15-2019, 08:26 AM   #28
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The 225/75R16 tires are 30" tires (actually about 29.5" tall). The 245/75R16 tires are 31" tires (largest installed on a TJ) are are the stock tire for my TJ Rubicon. They are 30.5" tall and are still smaller than the stock tires on the Sahara and Rubicon JKs (32" tires).

The 265/75R16 tires are 31.6" tall, just a fraction shorter than the 32" tires. They are a bit wider and you may experience some rubbing at full lock. However, if this bothers your, you can adjust the max the wheels will turn.

If I had a JK/JKU with 16" wheels that is what I would consider. However, if you look in the local Craigs List, you may find some JK/JKU take offs that you can get for less than the cost of new tires, and they will come with the aluminum wheels. A set on 17" Rubicon wheels would be preferred, but a set on 18" Sahara wheels may be easier to find. The height of both those stock tires is right at 32" and will fit your Sport without mechanical modification. You will have to have the tire size in the computer flashed so your speedometer and odometer are more accurate what ever you do.

Note: Just a quick look at my local CL and found JL Sahara 18" wheels and tires (32") for $700 for 5 and a set of JL Sport S 17" wheels and tires (LT245/75R17 - 31.5") tires and wheels for $450. I doubt you can get 5 tires for that. Even if you don't really like the tires, the JL Sport S 17" wheels have a decent appearance.
Thanks. I did buy a set of JK 17” for $200 of CL. But the dealer was giving me a hard time about using them on my sport since it had been configured for 16”. They were giving me the song and dance about TPS replacement and reprogramming the speedometer with $400 add on. So I stayed with the 16” and the 245s. Even then they weren’t happy about doing it. I just wanted to get 31” on the JK for the limited off road I do for fishing and hunting nothing extreme.
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Old 11-15-2019, 10:23 AM   #29
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Thanks. I did buy a set of JK 17” for $200 of CL. But the dealer was giving me a hard time about using them on my sport since it had been configured for 16”. They were giving me the song and dance about TPS replacement and reprogramming the speedometer with $400 add on. So I stayed with the 16” and the 245s. Even then they weren’t happy about doing it. I just wanted to get 31” on the JK for the limited off road I do for fishing and hunting nothing extreme.
There are two different TPMS sensors used in JK / JKUs. The older ones (pre-2012 as I recall) and the newer ones. It doesn't matter if it is a Sport, Sahara, or Rubicon. It is going to be one of two frequencies. If the tires you have are the newer frequency and your JK / JKU uses the older frequency you can either replace the TPMS sensors for $100 or so or you can get a ProCal widget or the like and disable the system. Or you can ignore the warning light. I would just buy a set of the right sensors off the internet and have them installed. Amazon, if you use them, or a vendor like Northridge or Quadratec (either typically price matches or offers forum discounts).
The ProCal will also let you adjust for the larger tire size, especially important if you have an automatic. But there are also apps that will let you do all that if you are an app type person.
It sounds like you need a better shop.
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Old 11-15-2019, 10:53 AM   #30
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Thanks. I did buy a set of JK 17” for $200 of CL. But the dealer was giving me a hard time about using them on my sport since it had been configured for 16”. They were giving me the song and dance about TPS replacement and reprogramming the speedometer with $400 add on. So I stayed with the 16” and the 245s. Even then they weren’t happy about doing it. I just wanted to get 31” on the JK for the limited off road I do for fishing and hunting nothing extreme.

Hang onto the 17" wheels if you like them and have the storage capacity. When it comes time to replace the tires, find another tire dealer as that one doesn't know his Jeeps. The TPMS pressure sensors are part of the valve stem and send a signal to the receiver mounted under the Jeep. It does not matter whether you have 16", 17", 18" or 20" wheels, the TPMS (if the right frequency) will send the signals. Many when changing wheels simply move the TPMS valve stems from the old wheels to the new wheels.

If you change the height of the tire (which you did) depending on how much you changed it, yes, you will have to get the Jeeps computer updated for the taller/shorter tires. Going up one size generally does not make a big difference in speedometer and odometer. In your case, going from 225/74R16 to 245/75R16 there is a 4% difference in the height and revolutions per mile (which is what the Jeeps systems and speedometer/odometer are based on. If your speedometer says 60, most likely you were actually going 57 since most are a bit optomistic. Now when you are going 60 you may be actually going 59.


Going from the 29" tire (225/75R16) to a 32" tire (255/75R17) which are the stock tire on Sport S and Rubicon JKs and come on some Sahara special edition (like my Chief with Recon wheels (silver) and BFG MTs), gives you a 9% change and at that point you might want to change the setting for your tires in the computer. While you can mentally change what speed you seeing (drive 55 in a 60 instead of driving 60) the setting for the Jeeps performance may be off enough to see a difference.

You can have the setting changed at a dealer - for a fee. You can purchase a dedicated calibration tool such as this:
https://www.quadratec.com/products/17609_5131.htm


They are now developing apps for smart phones to do this, and when paired with a OBDII reader, you can do a lot. I have not tried one of these, but I am tempted as it is only a $30 investment:


Both calibration systems do a lot more than just tire size. Before I would let a dealer do the change, I would buy one of these.

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