Speedo Recalibration?

[shembree]

Has anyone done a recalibration? I've seen references to an app that can do it, but I'm not sure where to find it.

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[oddlou]

There's a thread on this in another forum: https://www.f150forum.com/f31/correct-your-speedometer-error-no-flash-tune-required-361473/

I don't know whether anyone has actually done it on a '21, though. I'm considering doing it, but would like to know that it works on the 14th gen, first.

 

[Knickell]

Has anyone done a recalibration? I've seen references to an app that can do it, but I'm not sure where to find it.

You might be able to do it via ForScan, an auto shop in your area may also be able to do it. The benefit of having a certified shop do it, is they should give you a certificate of recalibration which may help you if you ever get pulled over for speed.

 

[Sentinel1201]

I went up a few sizes in tire size on my 21 Powerboost and used forscan to recalibrate the speedo. Just a few clicks and you are done, pretty easy to do. Look in the forscan thread.

 

[spacewhite_3.5]

I tried doing this last night but I could get the DTCs to clear so I reverted everything back to stock. I’m kinda new to forscan and I didn’t want to mess things up! Hopefully I’ll be able to figure it out this coming weekend. I’m have 35x11.50r20

 

[Bills]

I tried doing this last night but I could get the DTCs to clear so I reverted everything back to stock. I’m kinda new to forscan and I didn’t want to mess things up! Hopefully I’ll be able to figure it out this coming weekend. I’m have 35x11.50r20

I will be trying to sort this out over the weekend as well. 325x60x20 I am about 5mph over at highway speed so gonna get this done real quick.

 

[spacewhite_3.5]

@Bills If you can get yours to work I might have to pick your brain a little and see what I’m doing or not doing so I can get this done as well! I hate have my speedometer off

 

[Bills]

@Bills If you can get yours to work I might have to pick your brain a little and see what I’m doing or not doing so I can get this done as well! I hate have my speedometer off

like Sentinel said above it was pretty easy.

So first go through and save all of the stock (Asbuilt) settings just so you have them for backup
- there are videos online that show you how, and really that is the same procedure for the settings, so it is good practice before you really touch anything.

Next, once all the backup info is saved I went into the BCM module (Not the asbuilt portion)
- doing this it will allow you to change the tire circumference and it is easy to do.
- my original setting was at ( 2547). Tire size.com says that my 325x60x20 should be (2819) so that was the value I used. (First)…
- I did a test drive and found that I had gone too far.
-before is started at 65 indicated on speedo I was at 69 on gps
- at the new setting I was at 65 on the speedo, and 63 on gps.
- I had a swing from 4 slower than actual to 2-3 under actual
-doing the math (2819 - 2547 = 272). Then (272 / 7 = 38.86), then (38.86*3=117)
-So I took the (117) from the (2819) and entered the new circumference as (2702)
- Next test drive was spot on. Went to 25mph (perfect), (45 perfect), (55 perfect), (65 perfect), then a little faster and all speeds matched.

My truck never showed any DTC’s during this process. I went to the BCM module, changed only my tire circumference measurement, then hit “write”. Next do a relearn and do a test drive. I feel bad that I never did this to my 2017 and ran for a long time with a speedo off.

 

[NoCo150]

how does that size tire look? Where did your mileage go ? I think my tires look too small so I am considering the same. What tire did you get, can you post a picture? Thanks

I will be trying to sort this out over the weekend as well. 325x60x20 I am about 5mph over at highway speed so gonna get this done real quick.

 

[Bills]

how does that size tire look? Where did your mileage go ? I think my tires look too small so I am considering the same. What tire did you get, can you post a picture? Thanks

Here are a couple pics. Mileage took a bit of a hit, but my lead foot doesn’t help. I lost about 3mpg, still get some hybrid miles on electric maybe not quite as much but still gets some benefit from that.

 

[NoCo150]

Here are a couple pics. Mileage took a bit of a hit, but my lead foot doesn’t help. I lost about 3mpg, still get some hybrid miles on electric maybe not quite as much but still gets some benefit from that.

WOW that looks nice, did you put a lift on it too? Will that front tire rub when its flexed? It looks pretty close but could be just the pic angle. Thanks

 

[Seavee33]

like Sentinel said above it was pretty easy.

So first go through and save all of the stock (Asbuilt) settings just so you have them for backup
- there are videos online that show you how, and really that is the same procedure for the settings, so it is good practice before you really touch anything.

Next, once all the backup info is saved I went into the BCM module (Not the asbuilt portion)
- doing this it will allow you to change the tire circumference and it is easy to do.
- my original setting was at ( 2547). Tire size.com says that my 325x60x20 should be (2819) so that was the value I used. (First)…
- I did a test drive and found that I had gone too far.
-before is started at 65 indicated on speedo I was at 69 on gps
- at the new setting I was at 65 on the speedo, and 63 on gps.
- I had a swing from 4 slower than actual to 2-3 under actual
-doing the math (2819 - 2547 = 272). Then (272 / 7 = 38.86), then (38.86*3=117)
-So I took the (117) from the (2819) and entered the new circumference as (2702)
- Next test drive was spot on. Went to 25mph (perfect), (45 perfect), (55 perfect), (65 perfect), then a little faster and all speeds matched.

My truck never showed any DTC’s during this process. I went to the BCM module, changed only my tire circumference measurement, then hit “write”. Next do a relearn and do a test drive. I feel bad that I never did this to my 2017 and ran for a long time with a speedo off.

Nice! Thanks

 

[Bills]

WOW that looks nice, did you put a lift on it too? Will that front tire rub when its flexed? It looks pretty close but could be just the pic angle. Thanks

It is a 6” BDS lift as well. Yeah when loaded down and flexed I do get a small rub on plastic, not enough that I plan to bother with. I’ve only had it happen one time with a heavy load when off road. I think if I would have went with the coil overs up front it would likely not, but I went with the lift that used the stock shocks (for now)

 

[tewest86]

like Sentinel said above it was pretty easy.

So first go through and save all of the stock (Asbuilt) settings just so you have them for backup
- there are videos online that show you how, and really that is the same procedure for the settings, so it is good practice before you really touch anything.

Next, once all the backup info is saved I went into the BCM module (Not the asbuilt portion)
- doing this it will allow you to change the tire circumference and it is easy to do.
- my original setting was at ( 2547). Tire size.com says that my 325x60x20 should be (2819) so that was the value I used. (First)…
- I did a test drive and found that I had gone too far.
-before is started at 65 indicated on speedo I was at 69 on gps
- at the new setting I was at 65 on the speedo, and 63 on gps.
- I had a swing from 4 slower than actual to 2-3 under actual
-doing the math (2819 - 2547 = 272). Then (272 / 7 = 38.86), then (38.86*3=117)
-So I took the (117) from the (2819) and entered the new circumference as (2702)
- Next test drive was spot on. Went to 25mph (perfect), (45 perfect), (55 perfect), (65 perfect), then a little faster and all speeds matched.

My truck never showed any DTC’s during this process. I went to the BCM module, changed only my tire circumference measurement, then hit “write”. Next do a relearn and do a test drive. I feel bad that I never did this to my 2017 and ran for a long time with a speedo off.

This seems a lot easier than the instructions in the Mustang link. Did the instructions change on the 2021+ models? The instructions you wrote seems a lot me straight forward and easier.

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