2025 Lariat, 33” Tires and Forscan Tire Circumference

[mrjofus]

I got my new 275/70R18 Nitto tires and Eibach coilover level kit last week, and finally tried to update my tire circumference to match the new tires. My original circumference was 2409 and I needed to enter 2571. After multiple writes and relearns it seems that the 2025 Lariat maxes out at 2480. I saw another post in this forum from a user that was able to enter larger values on their 2024 Lariat and not get the errors I see on any value above 2480.

Are there any other 2025 Lariat owners that have 33” tires and have somehow managed to get a correct value programmed in? Thanks!

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[Alaska Steve]

Well, when I put 32’s on the day after I bought the truck, Forscan didn’t recognize my 2.7L engine so I couldn’t set the calibration for the 1” larger tires. Since then, I’ve noted that Google Maps, my GPS enabled dash cam, and the highway radar signs all match my indicated speed, even at 75mph. At this point, I‘m going to leave well enough alone.

 

[superj]

thats true, you might be good if you check it on gps. stock, the speedo seemed to read about 3mph faster then the truck was actually doing so you might be close to indicated speed now. or at least closer than before

 

[scubajosh77]

So I did the manual math when I put mine on and the speedo and gps were not the same. I used ChatGPt to calculate the error and provide an updated value for tire circumference. My speedo and GPS are identical now. 2537 was my final value. Entered with no issues

 

[stemplar]

What error(s) are you getting when you input your new number for the 33's?

I put 32" tires on my lariat fx4 and used forscan to adjust the tire circumference. I don't remember any details now, but I do recall getting an error that had to be cleared elsewhere in forscan, but my number stuck, the error went away after I figured out how to clear it, and my gps and radar detector (also with gps) agree exactly with what my dash says.

FWIW, the error I got was mentioned in a number of other threads and forums, and some people just ignore it while others clear it.

 

[mrjofus]

So I did the manual math when I put mine on and the speedo and gps were not the same. I used ChatGPt to calculate the error and provide an updated value for tire circumference. My speedo and GPS are identical now. 2537 was my final value. Entered with no issues

It would appear that Ford changed some limits for the 2025 such that the circumference can't be larger than 2480. I also looked into changing axle ratio to 3.50 with the original circumference value of 2409 in my truck. The truck won't accept anything besides a 3.73 ration it appears.

 

[mrjofus]

What error(s) are you getting when you input your new number for the 33's?

I put 32" tires on my lariat fx4 and used forscan to adjust the tire circumference. I don't remember any details now, but I do recall getting an error that had to be cleared elsewhere in forscan, but my number stuck, the error went away after I figured out how to clear it, and my gps and radar detector (also with gps) agree exactly with what my dash says.

FWIW, the error I got was mentioned in a number of other threads and forums, and some people just ignore it while others clear it.

If I entered anything larger than 2480 for circumference I get an error/warning from the BCM about the value being outside the range allowed. I can go through the PCM/TCM and AWD relearn, but I still wind up with a U0422 error from the PCM.

 

[scubajosh77]

It would appear that Ford changed some limits for the 2025 such that the circumference can't be larger than 2480. I also looked into changing axle ratio to 3.50 with the original circumference value of 2409 in my truck. The truck won't accept anything besides a 3.73 ration it appears.

That stinks.

 

[stemplar]

That stinks.

…except I don’t think that’s the case at all.

my Ranger is a 2025, and when I got these errors I found a ton of posts about them on f150 forums, ranger5g, bronco forums, etc. and thanks to them I was able to get the errors cleared and my tire size set correctly.

I didn’t take good notes about it because I remember flailing a bit and not seeing g success right away. I’m not sure when I’ll get a chance, but when I do I’ll connect FORScan again to check my settings.

 

[mrjofus]

…except I don’t think that’s the case at all.

my Ranger is a 2025, and when I got these errors I found a ton of posts about them on f150 forums, ranger5g, bronco forums, etc. and thanks to them I was able to get the errors cleared and my tire size set correctly.

I didn’t take good notes about it because I remember flailing a bit and not seeing g success right away. I’m not sure when I’ll get a chance, but when I do I’ll connect FORScan again to check my settings.

Thanks. I tried everything I could find but always got a warning about being outside the range, and the U0422 stuck.

 

[SEV3N8T1]

2025 Lariat, I also tried and got the same out of range messages. Spent a lot of time clearing errors as well. From searching all I found was the same posts about it being changed on the 2025’s.

 

[mrjofus]

2025 Lariat, I also tried and got the same out of range messages. Spent a lot of time clearing errors as well. From searching all I found was the same posts about it being changed on the 2025’s.

Good to know I'm not the only one!

I just ordered the Ford Performance Tune, so I'm anxious to see if that will allow me to update the PCM for tire size.

 

[SEV3N8T1]

Good to know I'm not the only one!

I just ordered the Ford Performance Tune, so I'm anxious to see if that will allow me to update the PCM for tire size.
[/

I don’t think the 2025 tunes were out yet, at least not the last I checked. 2025 Raptor is the only one available.

 

[mrjofus]

I don’t think the 2025 tunes were out yet, at least not the last I checked. 2025 Raptor is the only one available.

https://www.ford.com/product/ranger...0uzqt5yWikdQ8FWbaSzISNOzgiyQkg58aAlMaEALw_wcB

 

[mrjofus]

There’s never been a 2.7L Ranger before, so not sure why the Ford site says it doesn’t fit the 24/25. I bought it from Stage 3

https://www.stage3motorsports.com/m...er-27l-ford-performance-calibration-pack.html

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