FORScan Speedo Calibration for larger tires

[DanaBovender]

I believe the secret is to buy a $130 tire calibration tool from Rough Country or HyperTech....I picked up a used one for $100 off eBay.

Sponsored

 

[charwest]

Guys, need some help here.
OBD2 scanner should arrive today.
What is the verdict on the way of calibrating speedometer: BCM 726-12-01 code change or circumference change? Or it does not matter...

I went from stock 255/65R17 Bridgestone Duelers to 265/70R17 General Grabber ATX.
Is this a correct code I calculated? xxxx 0987 xxxx
Also where can I find circumference for my new tires?

Is it correct that 265/70R17 is kind of not "standard" size for Ranger and I will get U0422 code?

Thanks in advance.

1) does not matter. forscan with mm entry is easier.
2) can use various calcs for new tire circ. tiresize.com/calculator gives 2520 for your new tire

not sure what the actual mm you should put in, but it will be smaller than 2520. (0.967*2520)=2437mm may be a good starting point per prior threads, and then fine tune if not correlating with GPS speed while on cruise control.

most people posting seem to get the UO422 code, but no one has posted that there is any apparent problem associated with this. nor any way to get rid of it without a third party product.

 

[Igor]

Did anyone try to fine-tune the speedo with section 2 of the spreadsheet "Program with GPS tuning", instead of playing with millimeters?

 

[Igor]

Guys, any advise on why I don’t have write button against 726-12-01 entry?
Latest Forscan with extended trial license.

 

[Big Blue]

Guys, any advise on why I don’t have write button against 726-12-01 entry?
Latest Forscan with extended trial license.

Notice only the lower entry in each section has a write button? It writes both entry in the section.

 

[HarryD]

My 2020 with Sport Package came with Hankook AT M 255/65R17 and I swapped to Yokohama Geolandar AT G015 265/65R17. I assumed that my speedometer would run a bit slower with the change, so I used the code for OEM 265/65R17, 726-12-01 xxxx 0938 xxxx. After awhile I realized that my speedometer was actually running around 1 MPH fast.
I just changed it back to the original 0175 0910 9160, and my speedometer is now running true. Evidently, it must have been running 1 MPH fast with the original tires.

 

[Igor]

Notice only the lower entry in each section has a write button? It writes both entry in the section.

It worked. Thank you. Will check differences later.

 

[Commander Shepard]

I believe the secret is to buy a $130 tire calibration tool from Rough Country or HyperTech....I picked up a used one for $100 off eBay.

Any interest in loaning it out for a returnable deposit and fee? Say 30 bucks plus a 100$ refundable deposit? And s&h of course. Seems a shame to have to buy one to use once.

 

[DanaBovender]

Any interest in loaning it out for a returnable deposit and fee? Say 30 bucks plus a 100$ refundable deposit? And s&h of course. Seems a shame to have to buy one to use once.

once I get my wheels in and tires mounted and my calibration done I would use good faith and simply say you can use it for the cost of shipping to you and return to me., or we can all share the thing...so inexpensive and all the data and info I get from this forum it's not an issue for me. One less thing to keep track of anyway
I still have faith in society so we could actually do a pay it forward....

 

[Steven Gagliardi]

This is frustrating. I upsized my tires only slightly (3.6%) but I'd still like my speedometer and odometer to be accurate so I fooled around with it in ForScan but there's more work that needs to be done I think.

When I change 726-12-01 from its default xxxx 0934 xxxx (my stock tires were 265/60R18) to xxxx 0984 xxxx (new tires are 265/65R18) I get a persistent PCM DTC (U0422:00-2F) indicating "Invalid Data Received from Body Control Module"

It doesn't throw a CEL but it does make me wary of how the BCM change affects adaptive cruise control or other modules like ABS (though they're not reporting errors). There also seems to be an intermittent PSCM DTC (U0140:00-08) indicating "Lost Communication with Body ControL Module" that I don't understand since it only pops up every once in awhile.

I've tried it set to everything between 0984 and 0995 (since various decimal to hex calculators and methods give result in slightly different millimeter circumference values to convert) there ought to be a Ford blessed value in there somewhere since a 265/65R18 is the same outer diameter as the 265/70R17 Ford is saying is acceptable in the Fox kit press stuff. I guess I'll try a HyperTech and see if it works.

Hello.
So you had the 265/60/18s...I’m changing mine from 255/65/17 to the stock 265/60/18s tomorrow. So I should be able to use your stock code right? I’m new to forscan and still learning. But I assume this would work just fine. I don’t see a reason it would throw a code or CEL since it is a stock size. Am I wrong? Or should I be good to go once I change it?

 

[tng]

I came here to research this... then I realized if my odometer thinks I've gone less miles than I have, I'm okay with that. The engine and tranny will have spun as many times as my odometer thinks it did.

 

[Fawnbuster]

I used forscan and my Garmin GPS to get my speedometer to within less than a half a mile.per hour. Was off by 5 mph after getting the bigger tires.

$50 for the forscan cable and $10 for the one year license is much cheaper and more handy than a hundred bucks just for a speedometer tool.

 

[Msfitoy]

I used forscan and my Garmin GPS to get my speedometer to within less than a half a mile.per hour. Was off by 5 mph after getting the bigger tires.

$50 for the forscan cable and $10 for the one year license is much cheaper and more handy than a hundred bucks just for a speedometer tool.

Exactly same process for me...I did a bunch of other mods while I had the Forscan going...?

 

[Fawnbuster]

Exactly same process for me...I did a bunch of other mods while I had the Forscan going...?

Me too brother! Bambi mode, fake engine noise, parking lights, dingers and honks


Couldn't really notice a difference with the fake noise delete, I think my tinnitus canceled out the fake engine noise already! If I could only use forscan to disable the ringing in my ears from sirens I would have a peace and quite.

 

[kieefer]

You're welcome! Using the same formula, for your tire size I come up with 2519.

My new tire size 265/70R18 appears to be nearly identical, so I’m going to try your number of 2526 first.

thank you

THANK YOU BOTH!!!

Exactly what I was looking for!

My stock size 265/60/18 (2356) was recently upgraded to 265/70/18 and I changed my diameter in the BdyCM module to 2519.
I didn’t check prior to this change with my GPS but I’m dead-on now.
?

I’m going to bet that the fuel mileage calculator might have to be changed too? Anyone noticed a difference big enough to re-calculate?

Sponsored