DP tuner speedometer ?
Lead Driver
Joined: Jun 2003
Posts: 8,298
Likes: 24
From: Damon (South East Texas)
The speedometer is now reading correctly. I compared the readings of my truck and my wife's '07 Escape, that still has the original tires and is all stock, while we traveled down the road. We exchanged readings by phone and our speedometers were showing similar mph. The tire size is operator set, in the calibrator, by 1/4" increments and is compared to the stock size by VIN. The calculations are made electronicly. Then, the ABS module is reflashed thru the diagnostic port. My speedometer used to be 3-4 mph off.
Senior User
Joined: Feb 2006
Posts: 396
Likes: 2
The speedometer is now reading correctly. I compared the readings of my truck and my wife's '07 Escape, that still has the original tires and is all stock, while we traveled down the road. We exchanged readings by phone and our speedometers were showing similar mph. The tire size is operator set, in the calibrator, by 1/4" increments and is compared to the stock size by VIN. The calculations are made electronicly. Then, the ABS module is reflashed thru the diagnostic port. My speedometer used to be 3-4 mph off.
the best way i have found is the GPS, if you dont have one the next best way is to use the odometer over a 10 mile span on the highway and use mile markers.
its interesting that it used to be off 3-4mph, 3-4mph at what speed? 3-4 mph off at 20mph is lots worse then 3-4 mph off at 100
in other words, what percentage was it off?
Mine is within 2% no matter what the speed. But I have found I am even closer then that - more like 1% - not that the speedometer needs to even be that accurate, to me its more about the scheduled maintenance based on milege then anything else.
interesting topic here...
oh so once you are done using that device, you can unplug it, leave it home and drive around with everything being corrected??
Kenny
Lead Driver
Joined: Jun 2003
Posts: 8,298
Likes: 24
From: Damon (South East Texas)
Based on OE and "After" tire size, there was about a 3.5-3.75% difference in the speedometer reading. This is also based on 60-65 mph. This is the speed I run most of the time, to and from work. I used to allow for the percentage difference when calculating my mileage, but now the odometer reads more in line, with the calculations, without adding the difference.
Yes, once done, the device is removed and the speedometer in now reading the "adjusted" mileage.
I purchased mine on a rebate/ promotion deal for $207. More than some of the in-line devces, but no wiring needed and the device makes the calculations for you, based on the numbers that you input. It is supposed to be able to make adjustments up to a 54" tire diameter. You can also make allowances for gear ratio differences, too.
Yes, once done, the device is removed and the speedometer in now reading the "adjusted" mileage.
I purchased mine on a rebate/ promotion deal for $207. More than some of the in-line devces, but no wiring needed and the device makes the calculations for you, based on the numbers that you input. It is supposed to be able to make adjustments up to a 54" tire diameter. You can also make allowances for gear ratio differences, too.
Senior User
Joined: Feb 2006
Posts: 396
Likes: 2
Based on OE and "After" tire size, there was about a 3.5-3.75% difference in the speedometer reading. This is also based on 60-65 mph. This is the speed I run most of the time, to and from work. I used to allow for the percentage difference when calculating my mileage, but now the odometer reads more in line, with the calculations, without adding the difference.
Yes, once done, the device is removed and the speedometer in now reading the "adjusted" mileage.
I purchased mine on a rebate/ promotion deal for $207. More than some of the in-line devces, but no wiring needed and the device makes the calculations for you, based on the numbers that you input. It is supposed to be able to make adjustments up to a 54" tire diameter. You can also make allowances for gear ratio differences, too.
Yes, once done, the device is removed and the speedometer in now reading the "adjusted" mileage.
I purchased mine on a rebate/ promotion deal for $207. More than some of the in-line devces, but no wiring needed and the device makes the calculations for you, based on the numbers that you input. It is supposed to be able to make adjustments up to a 54" tire diameter. You can also make allowances for gear ratio differences, too.
sorry to raise the dead - is it locked to the one truck or can you program many trucks with the same device?
kenny
Elder User
Joined: Sep 2003
Posts: 582
Likes: 0
From: New Baden IL
just recalibraiting the speedo made that much of a difference,I have a 02 with 37 inch tires and need to get something to get more power out of it ( DP TUNER ) but you say recalibrating your speedo actually made a diiference,asplain yourself,and only 30.00 bucks!!!!!!!!
Sorry I didn't catch the question I think you were asking me. ABJ Ford in Trenton IL only charged me $30.00 to recal my ABS for my tire size. Then the technician kept the laptop hooked up while we went for a test drive.
The biggest reason for the increased SOTP feel is the shift points are now back to normal. Bigger tires makes your truck think it's going slower than it really is. Les
Post Fiend
Joined: Jun 2006
Posts: 9,714
Likes: 2
From: White Mnt's,New Hampshire
a lot of us have AE and can now adjust for tire size..
AutoEnginuity PC Scan Tool (USB)
i see you are in NJ?? maybe another member with AE lives close by and could help you out..
AutoEnginuity PC Scan Tool (USB)
i see you are in NJ?? maybe another member with AE lives close by and could help you out..
Lead Driver
Joined: Jun 2003
Posts: 8,298
Likes: 24
From: Damon (South East Texas)
Yes, it is VIN locked. The Calibrator can also be updated, online, to a PCM reprogrammer.
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1999, accuspeed, autoenginuity, calibrator, correction, dp, early, f350, forum, larger, merlin, recalibrate, speed, speedometer, tires, truspeed, tuner, wizard
