Hypertech Speedometer Calibration
Senior Member
Joined: Sep 2017
Posts: 152
Likes: 32
Package came in from from Rough Country today. Ordered Thursday, delivered Saturday. Read the instructions and set out to calibrate the speedometer. Found an area that I could set cruise and run 40MPH as required. Only took a couple of miles and Quickcal said it was ready. Found a place to park and applied the changes as per the instructions.
I was off by approximately 10%. I already knew that. After the calibration, I am running approximately +1 MPH vs. the GPS speed between 25MPH and 55MPH. I think that it is a result of rounding up the tenths in the MPH by the truck. I haven't had a chance to run above that yet, but will on Monday and report.
At this point, I am quite pleased. It couldn't have been much simpler as far as the process and seems to be accurate.
I was off by approximately 10%. I already knew that. After the calibration, I am running approximately +1 MPH vs. the GPS speed between 25MPH and 55MPH. I think that it is a result of rounding up the tenths in the MPH by the truck. I haven't had a chance to run above that yet, but will on Monday and report.
At this point, I am quite pleased. It couldn't have been much simpler as far as the process and seems to be accurate.
Senior Member
Joined: Jan 2013
Posts: 257
Likes: 76
From: Concord, NC
Did you run off the digital speedometer or the dial?
Package came in from from Rough Country today. Ordered Thursday, delivered Saturday. Read the instructions and set out to calibrate the speedometer. Found an area that I could set cruise and run 40MPH as required. Only took a couple of miles and Quickcal said it was ready. Found a place to park and applied the changes as per the instructions.
I was off by approximately 10%. I already knew that. After the calibration, I am running approximately +1 MPH vs. the GPS speed between 25MPH and 55MPH. I think that it is a result of rounding up the tenths in the MPH by the truck. I haven't had a chance to run above that yet, but will on Monday and report.
At this point, I am quite pleased. It couldn't have been much simpler as far as the process and seems to be accurate.
I was off by approximately 10%. I already knew that. After the calibration, I am running approximately +1 MPH vs. the GPS speed between 25MPH and 55MPH. I think that it is a result of rounding up the tenths in the MPH by the truck. I haven't had a chance to run above that yet, but will on Monday and report.
At this point, I am quite pleased. It couldn't have been much simpler as far as the process and seems to be accurate.
Senior Member
Joined: Sep 2017
Posts: 152
Likes: 32
My dial and digital match. When referencing the +1 MPH that is digital vs the GPS speed on the quickcal. It shows tenths. So 36.1 on the GPS is 37MPH on the truck speedometer, but it sometimes off a little more than 1 MPH. Still much better.
Senior Member
Joined: Sep 2017
Posts: 152
Likes: 32
I want to make sure that I answered your question. When doing the intial drive for adjustment, the Quickcal displays your trucks's digital speed as well as the GPS speed. When in the range (40MPH or above) it sounds an intermittent tone (beep) to let you know that you in the appropriate range.
If I still didn't answer your question, let me know.
If I still didn't answer your question, let me know.
Member
Joined: Dec 2017
Posts: 49
Likes: 0
From: Michigan, USA
The wrench issue is a non-issue. From the doyen of FORSCAN "Livinitup": After making the change for the tire size, go in to the programming area and choose the "PCM Module Initialization/relearn vehicle data" option and run that. After that look in the programming area for anything with the wording like "TCM relearn" and if you see it, run that too. You may not have TCM relearn if FORScan determines your truck doesn't have a separate TCM module.
I did this on my 2018 and it worked perfectly. It takes literally 10 seconds or less to clear the wrench, and it doesn't come back.
I did this on my 2018 and it worked perfectly. It takes literally 10 seconds or less to clear the wrench, and it doesn't come back.
Did you end up having to use the values of (726-12-01 xxxx 09E7 xxxx) in forscan to adjust to the correct tire or did you end up using a different value?