Tyre Size Calculator

Sat Jan 22, 2022 12:47 pm

: 2020-12-12 17_06_12-tyre .png (41.2 KiB) Viewed 1829 times

: 2020-12-12 17_06_12-tyre .png (41.2 KiB) Viewed 1829 times

WattoZ · Wed Feb 16, 2022 4:37 pm

Hey Stewart I’m trying to change my tyre size with the dongle I bought from you and forscan program.

Am I right in saying that I only change the 9034 to 9077 if I’m going to 33inch tyres.
I don’t change the numbers either side do I?

Wed Feb 16, 2022 8:05 pm

Correct, change those 4 numbers and leave the rest alone.
Do a backup before a change.

Wed Feb 16, 2022 8:15 pm

Yes and 0977 not 9077.

Richards935 · Tue Mar 22, 2022 5:01 pm

Hi

This might be a silly question

I have a 6 speed manual, and I have 285 65R18 tyres, using the calculator tells me the 09D2 is the number I need to enter.

is 09D2 higher than 0984, the max value i can enter?

Cheers

Tue Mar 22, 2022 5:49 pm

Richards935 wrote: ↑Tue Mar 22, 2022 5:01 pm Hi

This might be a silly question

I have a 6 speed manual, and I have 285 65R18 tyres, using the calculator tells me the 09D2 is the number I need to enter.

is 09D2 higher than 0984, the max value i can enter?

Cheers

0984 is the max you can enter which is lower than. 09D2.

Chowder · Fri Apr 08, 2022 11:14 am

Hi Stewart,

I've tried updating the tyre size in BdyCM AS built using both 09DC and 0977 and receive the same error prompt. Even after backing up and accepting the caution prompt the transmission is interrupted and no change registered. Have you seen this problem before?
Paul.

726-12-01 is xxxx-09DC-xxxx
726-12-01 is xxxx-0977-xxxx

Tyre size 285/70r17

Fri Apr 08, 2022 12:47 pm

Normal.

Press yes.

raptorx_ranger · Wed May 11, 2022 4:12 pm

Hey Guys,

Noob question warning: I am VERY new to FORScan. I've got a 2022 Ford Ranger Raptor X and I've tried to change the tyre size to compensate for the 35x12.5 I have.

I've inputted xxxx-0A8D-xxxx on line 726-12-01 and now I need to do a TCM re-learn but I'm not sure how or where to do that.

Would someone be able to post a screen shot of where I go to do it?

Cheers

Ben

Sat May 14, 2022 5:00 pm

raptorx_ranger wrote: ↑Wed May 11, 2022 4:12 pm Hey Guys,

Noob question warning: I am VERY new to FORScan. I've got a 2022 Ford Ranger Raptor X and I've tried to change the tyre size to compensate for the 35x12.5 I have.

I've inputted xxxx-0A8D-xxxx on line 726-12-01 and now I need to do a TCM re-learn but I'm not sure how or where to do that.

Would someone be able to post a screen shot of where I go to do it?

Cheers

Ben

dbmgreen · Thu May 26, 2022 10:55 am

Hi team,

I have a had a decent look around the forum, and just want to confirm, a couple of things before I buy.

For background I would consider myself reasonably IT savvy.

My daughter has a Ranger XLS and has put Raptor rims and Tyres on it. If anyone is wondering they fit** without mods to suspension IF you get a wheel alignment. She did add 2" level kit to the car at the same time.

**fit = they are very close to the steering knuckle. Tyre fitters said many cars come standard nearly as close. At full lock, they do just graze the steering knuckle. When I say full lock, I mean steering wheel hard against the stopper, if you go to full lock and then back off imperceptibly it doesn't touch, so I am thinking its actually the tyre squashing against it from the turn.

OK that's the background, now to my question.

The stock tyres are 265/65/17
The Raptor rims tyres are 285/70/17

The calculator gives me this for the Raptor rims/tyres
True Circumference mm: 2610
Ford Corrected Circumference mm: 2524
Required BCM value at 726-12-01 is xxxx-09DC-xxxx

6 speed automatic. Your max value is 0977 unless you have my custom TCM calibration installed. Anything over this value will cause a DTC.

The speedo reads about
4km under at 110kmhr
3km under at 90/100kmhr
2km under at 80kmhr

I don't want to make a change that throws and error, but would like to get the speedo largely correct.
I don't understand what "ford corrected" circumference is? VS max value.

If I input the "ford corrected" value, is this a value that will not error, but will get the speedo mostly correct?

Thanks in advance, sorry if I have not searched enough for the answer.

Thu May 26, 2022 12:44 pm

dbmgreen wrote: ↑Thu May 26, 2022 10:55 am Hi team,

I have a had a decent look around the forum, and just want to confirm, a couple of things before I buy.
For background I would consider myself reasonably IT savvy.

My daughter has a Ranger XLS and has put Raptor rims and Tyres on it. If anyone is wondering they fit** without mods to suspension IF you get a wheel alignment. She did add 2" level kit to the car at the same time.

**fit = they are very close to the steering knuckle. Tyre fitters said many cars come standard nearly as close. At full lock, they do just graze the steering knuckle. When I say full lock, I mean steering wheel hard against the stopper, if you go to full lock and then back off imperceptibly it doesn't touch, so I am thinking its actually the tyre squashing against it from the turn.

OK that's the background, now to my question.

The stock tyres are 265/65/17
The Raptor rims tyres are 285/70/17

The calculator gives me this for the Raptor rims/tyres
True Circumference mm: 2610
Ford Corrected Circumference mm: 2524
Required BCM value at 726-12-01 is xxxx-09DC-xxxx

6 speed automatic. Your max value is 0977 unless you have my custom TCM calibration installed. Anything over this value will cause a DTC.

The speedo reads about
4km under at 110kmhr
3km under at 90/100kmhr
2km under at 80kmhr

I don't want to make a change that throws and error, but would like to get the speedo largely correct.
I don't understand what "ford corrected" circumference is? VS max value.

If I input the "ford corrected" value, is this a value that will not error, but will get the speedo mostly correct?

Thanks in advance, sorry if I have not searched enough for the answer.

You have listed your vehicle as a PX Ranger XLS in your profile so I will assume it is PX1 and Pre MY15. If this is the case then the above does not apply to you and you cannot make any tyre size adjustment on that vehicle.

If it is a PX2 with 6 speed automatic. "Your max value is 0977 unless you have my custom TCM calibration installed".

dbmgreen · Thu May 26, 2022 1:04 pm

Ahh profile now amended... its a 2021 PX3

Thu May 26, 2022 6:06 pm

6 speed or 10 speed?

dbmgreen · Fri May 27, 2022 11:27 am

6 speed

I did purchase an SAEB ELM module as well, and downloaded / registered the software no problem

Fri May 27, 2022 12:39 pm

No problems.

6 speed so this applies.

If it is a PX2/PX3 with 6 speed automatic. "Your max value is 0977 unless you have my custom TCM calibration installed".

dbmgreen · Mon May 30, 2022 5:30 pm

So I reset the tyre size, initially to 285/70/17 09DC and this was too much compensation, went to 275/70/17 09B1, and the speedo looks good, BUT

Have the following error codes

PCM
Code: P0700 - Transmission Control System (MIL Request)
Status:
- DTC Maturing - Intermittent at Time of Request
- Malfunction Indicator Lamp is Off for this DTC
- Test not complete
Module: Powertrain Control Module

TCM
Code: P1635 - Tyre/Axle Out of Acceptable Range
Status:
- DTC Present at Time of Request
- Malfunction Indicator Lamp is On for this DTC
Module: Transmission Control Module

I tried to get PCM to relearn, but error is still there.
TCM relearn results in a "Service procedure interrupted" error.

What would be my next steps?
What am I doing wrong?

Mon May 30, 2022 6:03 pm

Sorry to sound like a pain in the arse but ...

It is becoming all to common question lately to a answer I have clearly put in the instructions.

Please re read and read posts above your post.

My main issue being the thread and other threads fill up with me repeating myself over and over then spending time clearing posts to a question that has been asked numerous times.

dbmgreen · Mon May 30, 2022 7:19 pm

For completeness

"If it is a PX2 with 6 speed automatic. "Your max value is 0977 unless you have my custom TCM calibration installed".

It's actually a PX3 but I have a feeling that's immaterial.

As a side note: 0977 is bang on for the 285s also cant thank you enough for this wonderful resource!

Cheers,
Dave

Mon May 30, 2022 7:23 pm

dbmgreen wrote: ↑Mon May 30, 2022 7:19 pm For completeness

"If it is a PX2 with 6 speed automatic. "Your max value is 0977 unless you have my custom TCM calibration installed".

It's actually a PX3 but I have a feeling that's immaterial.

As a side note: 0977 is bang on for the 285s also cant thank you enough for this wonderful resource!

Cheers,
Dave

Good call Dave, I will amend to say PX2/PX3.

Cheers for the pickup.

Marcus B · Sat Jun 04, 2022 6:38 pm

Hi , I'm new to the forum.
Im getting some new wheels n tyres for my 2021.75 ford ranger PX3 with 6 speed Auto.

Im going to run 285 65 18 Maxxis razor MT

When I put in the tyre size info into the tyre size calculator it says:

Required BCM value 09D2

6 speed Automatic - your Max value is 0977
Unless you have my custom TCM calibration installed.

Which value is the one I would enter on forscan?
09D2 or 0977

Also what is the custom TCM calibration?

I asked the ford dealership if they can adjust for larger tyres using forscan and they had no idea what I was talking about and said it couldn't be done.
You would think the ford dealership would be up with technology.
Do you know of any workshops gold coast or Brisbane that do these forscan re-calibrations ?

Thanks

Sat Jun 04, 2022 6:43 pm

Marcus B · Tue Jun 07, 2022 9:30 pm

If you have a custom tune done on a dyno does that overwrite the 0977 changes made for larger wheels that were done using via Forscan?

Am I best to get the dyno tune first then make the change 0977 for the larger wheels myself using Forscan?

Tue Jun 07, 2022 9:37 pm

Marcus B wrote: ↑Tue Jun 07, 2022 9:30 pm If you have a custom tune done on a dyno does that overwrite the 0977 changes made for larger wheels that were done using via Forscan?

Am I best to get the dyno tune first then make the change 0977 for the larger wheels myself using Forscan?

No tune will not be affected, which is basically firmware. You will only be change config data/as-built data.

Michael.james · Sat Jun 18, 2022 1:12 pm

Hey just a quick question, when changing the tyre circumference do we input the Ford corrected circumference or the true circumference figure??

Iv input the true circumference "2698" figure and my speed is now 7-8 km/h out??