Manual retrain

Some Random Guy

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How critical is the 6th gear retrain? I won’t be able to use 6th until I regear in 2 weeks. I’d like to fix my TPMS and speedometer until then.
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Some Random Guy

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Ok, looks like it won’t be happy if I change the tire size and don’t retrain (ess errors?). I’ll see if I can do it on I5 tomorrow. I think I can make due at just under 80, and maybe the cop will believe me if I do get pulled over.
I did get the TPMS done. I accidentally pulled the wrong plugs when trying to install, but got it figured out.
 

EJWF11

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… ya know, the amount of attention thats given to adjusting the speedometer is beyond me. Why is it so apparently critical? Are folks really haulin’ ass with big’ass tires to the point where they fret the po-po is gonna nip’m?? Just slow the roll and be mindful that the speedometer is off by a bit.

now adjusting the shift points on the automagic trans, that makes sense because of efficiency considerations.
 
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Some Random Guy

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It isn’t just the speedo, it’s the odometer and the miles to empty calculator too.
In my case I’m off by just under 20% (32.6 to 38.5). If it was just 35’s I might ignore it, but this is a jump to 39’s.
I also pass through 4 school zones on my way to work. I would’t want to accidentally be speeding with the poor stopping distance of a Wrangler pushing big tires and the children of the people that live here with no situational awareness.
 

EJWF11

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It isn’t just the speedo, it’s the odometer and the miles to empty calculator too.
In my case I’m off by just under 20% (32.6 to 38.5). If it was just 35’s I might ignore it, but this is a jump to 39’s.
I also pass through 4 school zones on my way to work. I would’t want to accidentally be speeding with the poor stopping distance of a Wrangler pushing big tires and the children of the people that live here with no situational awareness.
Okay, i see where youre coming from. Thanks for the explanation. 👍🏼

but you shouldnt worry about the children, after, theyll be easier to clear with the big ass tires 🤣
 

jeepoch

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Still fundamentally, bigger tires mean larger circumference which translates to less wheel revolutions per unit distance. This results in the speedometer reflecting a lower indicated vs true travelling speed. The difference is the percentage of the change in tire diameter. Worse yet, the higher the velocity the larger the error.

Telling a traffic officer that you willingly modified your vehicle's configuration, from factory specification, will only hurt (not help) your cause. Any tampering, even unintentional, may even yield you other maintenance related citations.

If your willing to go above the speed limit in general, running on larger rubber than stock will make it appear that your velocity is lower than it really is. So if you are thinking that the 10 to 15 over threshold is acceptable risk, you may in reality be facing a 20 over or more ticket. Maybe even a mandated court appearance, especially if out of state.

Running your rig with an inaccurate speedometer is like a pilot flying with a broken altimeter. It's just a matter of time until you find yourself in an unpleasant predicament.

Some things just require adjustment. Unless you are comfortable with performing all this velocity error math in your head (in real-time), don't trivialize your speedometer, odometer and distance-to-empty (DTE) guages. Life is too complicated enough already without more points on your driving record. I'm certain your insurance premium may seem way too expensive as it is.

On the bright side however, you'll retain a better trade-in value since the odometer will be clocking less miles travelled per true unit distance.

Then of course running out of fuel by relying on the distance-to-empty indication, whether accurate or not, just means you're either stupid, ignorant, poor (or more likely some combination of all three). Performing any kind of math is not likely in your vocabulary. The DTE is nothing more than an estimate and a crappy one at that. Way too many subtle variables such as quality of gas, tire pressure, wind speed even the Coriolis Effect of the Earth's rotation under your spinning tires.

Good luck. Happy Jeeping.
Avoid those school zones at all cost...
 
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Some Random Guy

Some Random Guy

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Still fundamentally, bigger tires mean larger circumference which translates to less wheel revolutions per unit distance. This results in the speedometer reflecting a lower indicated vs true travelling speed. The difference is the percentage of the change in tire diameter. Worse yet, the higher the velocity the larger the error.

Telling a traffic officer that you willingly modified your vehicle's configuration, from factory specification, will only hurt (not help) your cause. Any tampering, even unintentional, may even yield you other maintenance related citations.

If your willing to go above the speed limit in general, running on larger rubber than stock will make it appear that your velocity is lower than it really is. So if you are thinking that the 10 to 15 over threshold is acceptable risk, you may in reality be facing a 20 over or more ticket. Maybe even a mandated court appearance, especially if out of state.

Running your rig with an inaccurate speedometer is like a pilot flying with a broken altimeter. It's just a matter of time until you find yourself in an unpleasant predicament.

Some things just require adjustment. Unless you are comfortable with performing all this velocity error math in your head (in real-time), don't trivialize your speedometer, odometer and distance-to-empty (DTE) guages. Life is too complicated enough already without more points on your driving record. I'm certain your insurance premium may seem way too expensive as it is.

On the bright side however, you'll retain a better trade-in value since the odometer will be clocking less miles travelled per true unit distance.

Then of course running out of fuel by relying on the distance-to-empty indication, whether accurate or not, just means you're either stupid, ignorant, poor (or more likely some combination of all three). Performing any kind of math is not likely in your vocabulary. The DTE is nothing more than an estimate and a crappy one at that. Way too many subtle variables such as quality of gas, tire pressure, wind speed even the Coriolis Effect of the Earth's rotation under your spinning tires.

Good luck. Happy Jeeping.
Avoid those school zones at all cost...
Just to be clear I meant I might get pulled over only while doing the retrain because I have to hold 6th with pressure for 30 seconds.

For DTE I have no clue what my new gas mileage is, so if I have to drive any long distance I’d be guessing.

Does anyone know for the retrain if I go through the 2 sleep cycles first, then retrain or do I change tire size, retrain, then do 2 sleep cycles?
Edit: should have re-read instructions. It is spelled out pretty clear, 2 sleep cycles are after the special manual instructions are complete. Full reboot, start, stop, start, 6th for 30 seconds, then 2 sleep cycles.
 
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