setting larger tire size

WranglerMan

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Not sure what choices are available in the latest firmware but I’m running 11.08 and I have mine set to 34.49 for 315 KO2’s and it’s spot on from 75 mpg and down





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Not sure what choices are available in the latest firmware but I’m running 11.08 and I have mine set to 34.49 for 315 KO2’s and it’s spot on from 75 mpg and down
this shows how inaccurate this process really is. I'm running the latest firmware and as stated before my tires measured out to 33-7/8" with the weight of the jeep on them. Right now I have the tire size set to whatever was closesest to 34.25 and i'm still right about 1.2 or 1.3 mph off.

Not complaining because the process of changing it and checking is rather simple. Hopefully this thread makes it easier for someone in the future.
 

WranglerMan

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this shows how inaccurate this process really is. I'm running the latest firmware and as stated before my tires measured out to 33-7/8" with the weight of the jeep on them. Right now I have the tire size set to whatever was closesest to 34.25 and i'm still right about 1.2 or 1.3 mph off.

Not complaining because the process of changing it and checking is rather simple. Hopefully this thread makes it easier for someone in the future.
Yes it’s a tad bit inaccurate but who knows how far the speedo was off before hand form the factory
 

Uhdinator

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Had to set mine @ 31.75" for 32" measurement to get within 1 MPH difference from the speedo. It's likely the speedo was not exact from the factory. 32" as measured resulted in 2-3 mph off depending on speed.
 

Motoristx

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I'm having some issues getting the Speedo to match the GPS on the phone, with my Taser JL Mini.

First off, I want to say I love this product. I use the Lightshow at work as I'm a firefighter captain and EMT at a chemical plant, and people recognize the the lightshow as an emergency vehicle. I love all the features it offers.

We just put some 38's on the JLUR EcoDiesel. When measured they are about 36.5 inches, so I chose the closest setting to that. I did't check it with the stock setting, though now I wish I did. The Speedo is about 2 mph off. That's not bad, at 60 on the speedo it shows 62 on the GPS, and when I drive by those radar things on the side of the road they show 62 as well.

I would prefer it to be spot on, or at the least showing faster on the speedo than I'm actually driving. See I have a habit of speeding, and the cops seem to only pull over people going 10+ over the speed limit. I have a theory, that I can always drive 8 mph over, and only get warnings, if pulled over at all (unless in a school zone, then you better be spot on!).

With all this being said, I changed the setting to 40 inches, even though I have 38's, just to start to narrow down the perfect setting for me and my driving style. Unfortunately, it still showed 2 mph off. I understand doing the sleep cycles to allow things to save properly, and after several cycles it still the same.

I use Apple computer to upgrade the firmware (11.2.1 4.23.20) and I understand that using the Apple to upgrade firmware sometimes deletes the upgrade key, so I put my key back in, even though other features have been working. After a few more sleep cycles, if this problem persists, I may need some help!

Does it seem like I may be missing anything here? I have been doing full reboots after each of the setting changes as well.
 

Arctric

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I'm having some issues getting the Speedo to match the GPS on the phone, with my Taser JL Mini.

First off, I want to say I love this product. I use the Lightshow at work as I'm a firefighter captain and EMT at a chemical plant, and people recognize the the lightshow as an emergency vehicle. I love all the features it offers.

We just put some 38's on the JLUR EcoDiesel. When measured they are about 36.5 inches, so I chose the closest setting to that. I did't check it with the stock setting, though now I wish I did. The Speedo is about 2 mph off. That's not bad, at 60 on the speedo it shows 62 on the GPS, and when I drive by those radar things on the side of the road they show 62 as well.

I would prefer it to be spot on, or at the least showing faster on the speedo than I'm actually driving. See I have a habit of speeding, and the cops seem to only pull over people going 10+ over the speed limit. I have a theory, that I can always drive 8 mph over, and only get warnings, if pulled over at all (unless in a school zone, then you better be spot on!).

With all this being said, I changed the setting to 40 inches, even though I have 38's, just to start to narrow down the perfect setting for me and my driving style. Unfortunately, it still showed 2 mph off. I understand doing the sleep cycles to allow things to save properly, and after several cycles it still the same.

I use Apple computer to upgrade the firmware (11.2.1 4.23.20) and I understand that using the Apple to upgrade firmware sometimes deletes the upgrade key, so I put my key back in, even though other features have been working. After a few more sleep cycles, if this problem persists, I may need some help!

Does it seem like I may be missing anything here? I have been doing full reboots after each of the setting changes as well.
Wondering if you ever sorted this problem out? Having the exact same issue here.
 

Motoristx

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Wondering if you ever sorted this problem out? Having the exact same issue here.
Solved! It's a bit of a slow process. First off I have an EcoDiesel, it has a pump that runs a few mins after its shut down. This possibly requires a longer shutdown... So the Jeep needs 2 long shutdowns after a change in tire size. For me that meant changing the setting, doing a full reboot, starting it up letting it run for a min, then shutting it down and waiting 10 mins. I waited 10 mins because that pump runs for like 6 mins on shutdown. Then I started it up and let it run for a min, then again, shut it down and let it set for 10 mins. After the 2 shutdowns for 10 mins each, the tire size stuck and the speedo had changed as compared to my GPS.

The issue is, this has to be done for every change, so if you're fine tuning the speedo to match a GPS, every little change needs to go through this same process. I ended up just driving it around like normal and every 3rd or 4th start, I just pulled up the GPS to compare and see what the latest setting did. I ended up taking 2 days with my GPS on the dash making fine tune adjustments till i was happy with it.

Hope this helps.
 

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