Recalibrating speedometer / sensors after lift and bigger tires

[alzev]

@Al or Bill, just looking to know if this calibration worked out well after a few weeks of driving? Also, did either one of you have your truck equipped with Active Assist 2.0 prep (aka BlueCruise prep) package? I'm hearing from local tuner shops they are concerned or had issue with messing with any speedo settings on a truck with this package. thanks for any help/updates!

Yes my truck has the active 2.0 package no issues at all my Speedo is still probably 2 mph at 70 off which I’ll tweak eventually but it is super easy. I don’t remember the thread but after you get your diameter in mm you want to multiply that by a number and it puts you pretty close. If I go over the standard math times pi Speedo was still pretty off so I don’t know if it’s just the with forscan or the way Ford is converting the numbers in the system.
All in all it’s super simple and shouldn’t take you more than 5 min to get it setup and then go take a couple passes to get it really dialed.
I have driven a good couple thousand miles and used the active cruise on long trips with no issues.

Sponsored

 

[cowboytk]

So I have a set of 285/65r20’s coming in tomorrow. I have called a couple dealers getting the it’s not lawful to change Speedo etc. (like the roush lifted trucks or Shelby doesn’t have a corrected Speedo) I am afraid of the Forscan tool cause it’s completely new to me and all I have is iOS products (MacBook-iPad etc) and there is a bit of confusion as to whether I can use my MacBook to correct the tire size. If anyone can guide me to the right area I would be grateful. This is the first vehicle I have ever owned where I cannot get a hand held programmer. Little lost. Thanks in advance

 

[flynavy]

So I have a set of 285/65r20’s coming in tomorrow. I have called a couple dealers getting the it’s not lawful to change Speedo etc. (like the roush lifted trucks or Shelby doesn’t have a corrected Speedo) I am afraid of the Forscan tool cause it’s completely new to me and all I have is iOS products (MacBook-iPad etc) and there is a bit of confusion as to whether I can use my MacBook to correct the tire size. If anyone can guide me to the right area I would be grateful. This is the first vehicle I have ever owned where I cannot get a hand held programmer. Little lost. Thanks in advance

There is a tool specific to speedo for around 150-200 bucks if you don’t want to mess with forscan. Can’t remember the name but it will probably pop up on Google.

 

[cowboytk]

There is a tool specific to speedo for around 150-200 bucks if you don’t want to mess with forscan. Can’t remember the name but it will probably pop up on Google.

I have looked at the hypertech and the rough country and they seem nice but wanted to get perspective from those who have products already.

 

[flynavy]

I have looked at the hypertech and the rough country and they seem nice but wanted to get perspective from those who have products already.

Gotcha, I did forscan on my last truck and it wasn’t too bad. Cheap OBD reader from Amazon and the free software. I might have paid 5.00 or something for a year because I’m impatient but I think it’s free. There’s a ton of tire data already out there so you can plug and play. Ie: someone had 285/65/20 BFG tires so the value was something like G24X… so I tried that and tested speed and it worked fine.

 

[alzev]

It’s very simple with the new version of forscan if you follow the directions it will take you 5 min. You will have to play the formula alittle to get the speedo accurate but it is super easy to do. I use my MacBook but I have boot camp running windows as well.

 

[egap69]

My dealer is using forescan to program speedo for larger tires. Their Ford software they use for earlier models won’t work on the 21s.

 

[AutonomousHybridF150]

Too funny that they refuse to do things that Ford won’t allow us to do through the menus.

 

[sswalters]

Thanks for replying bill. Yeah I basically just went back last night and rather than using the number that the calculator and wheel MFG kicked out changed tire size to 34” from 34.6 did the math and kept dropping down the circumference until I got goose to gps. I’m now within 1-2mph @70 mph of what gps is reading and probably close enough.

Interesting. I went from the stock tires, to a 2" level and 295/60/20 tires, and my GPS and speedo are almost identical. I'd see they are perfect. Are we sure we need the speedo calibrated? I hear there is a device mounted begins the panel since the software is not yet available. Does it serve any other function? I'm tempted to leave things alone since the speedo is correct.

 

[Littlefield82]

Has anyone successfully recalibrated their Speedo that doesn’t have any coding experience? I’d like to tackle it but the jargon used in the instructions is like a foreign language to me.

 

[Littlefield82]

Has anyone successfully recalibrated their Speedo that doesn’t have any coding experience? I’d like to tackle it but the jargon used in the instructions is like a foreign language to me.

I did this yesterday and it worked fine but I didn't get any errors as described in the writeup so maybe that's only for the Mustangs.

 

[TrevTitan45]

Interesting. I went from the stock tires, to a 2" level and 295/60/20 tires, and my GPS and speedo are almost identical. I'd see they are perfect. Are we sure we need the speedo calibrated? I hear there is a device mounted begins the panel since the software is not yet available. Does it serve any other function? I'm tempted to leave things alone since the speedo is correct.

Hi, I just purchased 295/65r20 Nitto Ridge Grapplers and have the same concern regarding speedo. Are you still not having any issues without recalibration?

 

[Bignemo]

Gotcha, I did forscan on my last truck and it wasn’t too bad. Cheap OBD reader from Amazon and the free software. I might have paid 5.00 or something for a year because I’m impatient but I think it’s free. There’s a ton of tire data already out there so you can plug and play. Ie: someone had 285/65/20 BFG tires so the value was something like G24X… so I tried that and tested speed and it worked fine.

Hi, I just purchased 295/65r20 Nitto Ridge Grapplers and have the same concern regarding speedo. Are you still not having any issues without recalibration?

I have the same tire and am wondering tge same

 

[SanJuanTech]

I will be re-calibrating mine either later today or tomorrow after a 4" BDS lift with 35x12.5 Tires using FORscan. Looks like I am off 2.5 MPH at 70MPH using a GPS. I will use this calculator see how accurate it is.

 

[gspete]

Interesting. I went from the stock tires, to a 2" level and 295/60/20 tires, and my GPS and speedo are almost identical. I'd see they are perfect. Are we sure we need the speedo calibrated? I hear there is a device mounted begins the panel since the software is not yet available. Does it serve any other function? I'm tempted to leave things alone since the speedo is correct.

So, the re-calibration process, is it for speed and/or is it for transmission shift points?

Sponsored