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Yes, the needle is 1-2 mph higher than digital. The digital is about 1 mph higher than my GPS speed readout.
 

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Yes, the needle is 1-2 mph higher than digital. The digital is about 1 mph higher than my GPS speed readout.
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Hmmm. I just got rid of a car that had a 3 mph inaccuracy..... my hyundai Elantra...... that ultimately led to a class action lawsuit that resulted in a whole lot of people getting rebates back due to inaccurate mpg. Hyundai had to restate their mpg due to that inaccuracy in their onboard computers. I hope I do not go down that path again due to inaccurate speedo. I suspect the difference in GPS May be built in % of error. Also I assume any difference in tire size is calibrated somewhere along the way between models with different tire sizes. Next time I am out, I will have to see if there is a difference in mine....I have not noticed but I have only had for about a week.
 

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Yes, the analog speedometer reads higher than the digital speedometer. The digital version reads at least 1 mph higher than roadside radar signs show. This lead me to think that the odometer might be off too, but a trip that Google shows at 201 miles came out to 200.6 on my odometer...pretty much spot on.
 

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2021 Sienna LE AWD "Mr. Sparkollz"
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Yes; the analog 70 mph (corroborated by 70 mph setting on the cruise control) corresponds to 68 mph on GPS, which is 3% difference. Not my favorite feature, but I'll let it slide :)
 
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Yup have noticed this too. But I don't mind because when I set cruise to 80 analog on the highway in a 65 I'm really only going 78-79, which is OK with me because I get to feel like I'm going 80 without jumping into the 15+ over category should I get lit up.
 

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Yup have noticed this too. But I don't mind because when I set cruise to 80 analog on the highway in a 65 I'm really only going 78-79, which is OK with me because I get to feel like I'm going 80 without jumping into the 15+ over category should I get lit up.
There is always a rebel in the group. ;)
 

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I seriously doubt this, but would be happy to be corrected
According to the Navigation and Multimedia Owners Manual (pg. 117), the navigation system uses tire turning data and is designed to work with the factory-specified tires for the vehicle. Installing tires larger or smaller than the original may cause inaccurate display of the current position.
 

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I noticed it too. I thought minivan and hybrid drives want to drive slow? You will always be below the speed limit. LOL!

I forget which car had the 1st digital speedometer but I prefer it to the gauge. Plus I'm old and have had so many inaccurate and not functional speedometer, gas & temp gauges this doesn't bother me. Plus my Garmin Dash GPS tells me the speed I'm going. Then again I think the military builds inaccuracy into the GPS system on purpose.

The worst for my OCD was a Chrysler that had a traditional clock in the dash right above the digital one on the electronic display. They were never on the same time GRRRR!
 

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According to the Navigation and Multimedia Owners Manual (pg. 117), the navigation system uses tire turning data and is designed to work with the factory-specified tires for the vehicle. Installing tires larger or smaller than the original may cause inaccurate display of the current position.
Correct, but last I checked the Navigation System is separate from the speedo
 

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Tire diameter varies with wear and that in turn affects speedo accuracy. A new tires has tread depth of about 9 mm and worn out it is 1.6mm. That's a total variation in diameter of 14.8 mm. For P235/65R17 which have a diameter of 737 mm nominal, that is 2% variation over the life of the tire. On top of that diameters vary from brand to brand for the same size so the total accuracy just based on tire size alone is likely to be no better than 5%.

My understanding was the Hyundai class action lawsuit was that Hyundai misrepresented the fuel economy of certain Hyundai vehicles. It didn't have anything to do with speedo error. But maybe I have the wrong law suit.
 

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Tire diameter varies with wear and that in turn affects speedo accuracy. A new tires has tread depth of about 9 mm and worn out it is 1.6mm. That's a total variation in diameter of 14.8 mm. For P235/65R17 which have a diameter of 737 mm nominal, that is 2% variation over the life of the tire. On top of that diameters vary from brand to brand for the same size so the total accuracy just based on tire size alone is likely to be no better than 5%.

My understanding was the Hyundai class action lawsuit was that Hyundai misrepresented the fuel economy of certain Hyundai vehicles. It didn't have anything to do with speedo error. But maybe I have the wrong law suit.
 

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Yes, the needle is 1-2 mph higher than digital. The digital is about 1 mph higher than my GPS speed readout.
Same. I just noticed it on my first relatively long road trip last weekend (about 250 miles round trip). Was using the GPS on my phone, which displays my speed next to the speed limit in the area I'm driving through - and I noticed the GPS was showing me going 72-73mph when my speedometer needle was right on 75. It's a little annoying, but at the very least, I count myself lucky that it's not erring in the other direction - higher.
 
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2021 Sienna LE AWD "Mr. Sparkollz"
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The worst for my OCD was a Chrysler that had a traditional clock in the dash right above the digital one on the electronic display. They were never on the same time GRRRR!
Those clocks may have been in different time zones (Chrysler Digital and Chrysler Analog zones)
 

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Then again I think the military builds inaccuracy into the GPS system on purpose.
When GPS was first allowed for civilian use, there was an inaccuracy added in. That inaccuracy has since been removed(about 15-20 years ago)and everyone has access to the same accuracy as the military.
 
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