My spedometer is lying to me.
Professional
Joined: Aug 2007
Posts: 158
Likes: 1
From: St. Paul, MN
RE: My spedometer is lying to me.
Since even the same size tires vary from brand to brand, go to Tire Rack and look up the specs for your tire. Buy a Superchips and recalibrate or go to the dealer and have them do it. They may not even charge you, as it is just a quick hook-up through the OBD II port.
Champion
Joined: Aug 2005
Posts: 3,313
Likes: 8
RE: My spedometer is lying to me.
When looking at tire specs,
pay attention to the
'revolutions per mile' number that will lie between 600 to 750
this gives more accurate info about how the speedo should be calibrated
that the tire numbers like 235 70 R17, etc
Many Dodge dealerships turn over technicians so rapidly that many don't have the training to correct the speedo:
old post:
---
originally posted by grfraz
Augusta GA
Here is the recipe.
1) Have the tech plug his hand held into the OBD port and turn it on. A menu
screen comes up with a bunch of info. Select YES to go to next screen.
2) On this screen select menu item 1, "DRB III Standalone" to go to next screen.
3) On this screen select menu item 1, "1998-2005" to go to next screen.
4) On this screen select menu item 1, "All" to go to next screen.
5) On this screen select menu item 5, "Antilock Brakes" to go to next screen.
6) On this screen select menu item 9, "Miscellaneous" to go to next screen.
7) On this screen select menu item 2, "Set Pinion Factor" to go to next screen.
8) On this screen there are a several tire sizes and Other. Select menu item 8,
"Other" to go to next screen.
9) On this screen there are two items, an Axle Size, (9.25" on the 1500's and
10.5" on the 25/3500's) and Other. Select menu item 1, "9.25" Axle" (10.5 in
your case) to go to next screen.
10) You have now arrived at the point in this process where you will enter the
revolutions per mile for your tire size. Select the menu box for RPM. It will
indicate 400. Here is where the tech will change the revs per mile with either
the up or down arrow. It will take a while to go from 400 to 604 (for the BFG
315's) so be patient. As you are waiting on him to finish, take this time to let
him know that he shouldn't charge you more than say $20.00, especially since you
trained him on this procedure.
11) The last step is to select "OK" and the changes will be excepted, then the
hand held will display "Reprogramming Successful".
Good luck!
======
There is an online Java calculator to compute revolutions per mile at:
http://pw1.netcom.com/~sgalaba/tiresize.htm
pay attention to the
'revolutions per mile' number that will lie between 600 to 750
this gives more accurate info about how the speedo should be calibrated
that the tire numbers like 235 70 R17, etc
Many Dodge dealerships turn over technicians so rapidly that many don't have the training to correct the speedo:
old post:
---
originally posted by grfraz
Augusta GA
Here is the recipe.
1) Have the tech plug his hand held into the OBD port and turn it on. A menu
screen comes up with a bunch of info. Select YES to go to next screen.
2) On this screen select menu item 1, "DRB III Standalone" to go to next screen.
3) On this screen select menu item 1, "1998-2005" to go to next screen.
4) On this screen select menu item 1, "All" to go to next screen.
5) On this screen select menu item 5, "Antilock Brakes" to go to next screen.
6) On this screen select menu item 9, "Miscellaneous" to go to next screen.
7) On this screen select menu item 2, "Set Pinion Factor" to go to next screen.
8) On this screen there are a several tire sizes and Other. Select menu item 8,
"Other" to go to next screen.
9) On this screen there are two items, an Axle Size, (9.25" on the 1500's and
10.5" on the 25/3500's) and Other. Select menu item 1, "9.25" Axle" (10.5 in
your case) to go to next screen.
10) You have now arrived at the point in this process where you will enter the
revolutions per mile for your tire size. Select the menu box for RPM. It will
indicate 400. Here is where the tech will change the revs per mile with either
the up or down arrow. It will take a while to go from 400 to 604 (for the BFG
315's) so be patient. As you are waiting on him to finish, take this time to let
him know that he shouldn't charge you more than say $20.00, especially since you
trained him on this procedure.
11) The last step is to select "OK" and the changes will be excepted, then the
hand held will display "Reprogramming Successful".
Good luck!
======
There is an online Java calculator to compute revolutions per mile at:
http://pw1.netcom.com/~sgalaba/tiresize.htm