Speedometer and Odometer

carogers86 · 11-21-2010, 09:09 PM

Hi all,

I've been a "lurker" on this forum for some time now, and can attest to staying up late with the glowing screen of my iPad as my gateway to information (against the wishes of a sleeping wifey). I have read older posts acknowledging that the BMW speedometer is off ~ 5mph.

While my designated driver was doing her job late the other night, I sat shotgun staring at the speedometer's display of 75mph. At the same time, I knew to subtract 5mph.

This got me thinking. What if I were to drive the car for an hour, uninterrupted at what the speedometer calls 75mph, would the odometer roll over another 75 miles or 70miles? Or is the odometer calibrated differently and work independent of the speedometer? We are all pretty busy, and I don't think there are too many people out there who could dedicate any time to doing this, but just pondering...

Also, I am new here as I am sure many can tell. Please excuse me if I did not follow protocol correctly. This is a great forum.

arctic330i · 11-21-2010, 09:10 PM

Nice first post! lol Welcome!

Dr. G · 11-21-2010, 09:16 PM

The odometer would roll over 70 miles and not 75 as far as I know.

jonni44 · 11-21-2010, 09:16 PM

haha wow i cant believe i didnt put 2 and 2 together when my gps always read that i was going slower than my speedometer said i was. as for your question, sorry bro i have no idea lol. Although i know my buddies speedometer/odometer are off because of his tire size and his odometer read 240k when he actually has 280k.

jopa489 · 11-21-2010, 09:23 PM

The offset is programmed into the speedometer, and does not effect the trip computer or odometer. Those are 100% accurate.

chromisdesigns · 11-21-2010, 09:41 PM

Odo is correct, speedo error is programmed in, and cannot be corrected in more recent models. You used to be able to enter a "speedometer correction" factor back in E36 days, and the speedo would be right, but then the odo was off! They removed that "feature" in subsequent years. It was originally intended to correct for tire size changes, not to fix the speedo error, but that's how everybody used it.

11-21-2010, 09:09 PM	#1
carogers86 Private First Class 72 Rep 155 Posts Drives: BMW 335i Coupe Join Date: Jul 2010 Location: San Francisco iTrader: (0)	Speedometer and Odometer Hi all, I've been a "lurker" on this forum for some time now, and can attest to staying up late with the glowing screen of my iPad as my gateway to information (against the wishes of a sleeping wifey). I have read older posts acknowledging that the BMW speedometer is off ~ 5mph. While my designated driver was doing her job late the other night, I sat shotgun staring at the speedometer's display of 75mph. At the same time, I knew to subtract 5mph. This got me thinking. What if I were to drive the car for an hour, uninterrupted at what the speedometer calls 75mph, would the odometer roll over another 75 miles or 70miles? Or is the odometer calibrated differently and work independent of the speedometer? We are all pretty busy, and I don't think there are too many people out there who could dedicate any time to doing this, but just pondering... Also, I am new here as I am sure many can tell. Please excuse me if I did not follow protocol correctly. This is a great forum.
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11-21-2010, 09:10 PM	#2
arctic330i Lieutenant Colonel 126 Rep 1,984 Posts Drives: F15 35i Join Date: Aug 2010 Location: Gainesville, Fl iTrader: (8) Garage List 2014 BMW X5 [0.00] 2006 BMW 330i E90 [8.08] 2013 BMW 335is [10.00]	Nice first post! lol Welcome! __________________ See my full mod list in my garage
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11-21-2010, 09:16 PM	#3
Dr. G Major General 278 Rep 5,062 Posts Drives: Black e92 335i Join Date: Apr 2010 Location: Brampton, Ontario iTrader: (32) Garage List e92 BMW 335i [8.84]	The odometer would roll over 70 miles and not 75 as far as I know.
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11-21-2010, 09:16 PM	#4
jonni44 Second Lieutenant 7 Rep 275 Posts Drives: i8 Join Date: Feb 2009 Location: Chestermere, AB iTrader: (4)	haha wow i cant believe i didnt put 2 and 2 together when my gps always read that i was going slower than my speedometer said i was. as for your question, sorry bro i have no idea lol. Although i know my buddies speedometer/odometer are off because of his tire size and his odometer read 240k when he actually has 280k.
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11-21-2010, 09:23 PM	#5
jopa489 Major General 122 Rep 6,594 Posts Drives: Anything with Wheels Join Date: Mar 2009 Location: USA iTrader: (9)	The offset is programmed into the speedometer, and does not effect the trip computer or odometer. Those are 100% accurate. __________________ X7 LCI // Incoming C7 ZR1 ZTK // Sebring + TRX // Hydro + Raptor Gen1 Roush // Tuxedo
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11-21-2010, 09:41 PM	#6
chromisdesigns Lieutenant Colonel 45 Rep 1,754 Posts Drives: 2008 BMW 335i sedan Join Date: Jan 2010 Location: San Francisco iTrader: (0)	Odo is correct, speedo error is programmed in, and cannot be corrected in more recent models. You used to be able to enter a "speedometer correction" factor back in E36 days, and the speedo would be right, but then the odo was off! They removed that "feature" in subsequent years. It was originally intended to correct for tire size changes, not to fix the speedo error, but that's how everybody used it.
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