Speedometer calibration after lift/tires

[AAOO]

The angle of the strut assemble itself has not changed the overall linear dimension has increased but the angle the strut assembly is installed at has stayed the same.

The angle of the dangle is proportional to the heat of the meat. Furthermore, the heat of the meat is inversely proportional to the angle of the dangle and directly proportional to the mass of the ass.

 

[mrpositraction]

Did anyone ever figure this out? I have a 2019 with the same issue. Anything over 33.00 and it throws a wrench. Resent PCM KAM and TCM KAM with no change. Only way to get the wrench to go away is to set anything less than 33.01"

FYI, I am running a 35" tire

 

[cmurphy2]

Bully Dog BDX tuner will allow you to set tire size over 33 in menu I saw in mine.


Sent from my iPhone using Tapatalk

 

[John Ehrhardt]

I wanted to bump this thread. Seems like a tuner is the only option? Has anyone with larger tires done anything to address gearing, speedometer, or anything else?

I have 285/75R18, 34.8” tires and have the speedometer showing 60 mph when my GPS shows 65. And yes they fit with an ikon lift and so does the spare.

 

[Expedition Dave]

I removed this.

 

[SWTB0BCAT]

I have a 2020 and looking for a solution also.

 

[DWs-TTEB]

ForScan. I did a write up on this recently here:

https://www.expeditionforum.com/threads/what-have-you-done-to-your-4th-gen-this-week.40264/page-102

 

[SWTB0BCAT]

ForScan. I did a write up on this recently here:

https://www.expeditionforum.com/threads/what-have-you-done-to-your-4th-gen-this-week.40264/page-102

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No problems after the TCM relearn? Also, what size tires do you have?

 

[DWs-TTEB]

No problems after the TCM relearn? Also, what size tires do you have?

To date no wrench/DTCs have been thrown.

Tires size LT285/65R18 wheels -12mm offset 18”x9”

 

[John Ehrhardt]

Thanks for the updates, this gives me hope, but I'm still a little confused. It sounds like you added a custom tune and then used forscan to relearn/reset the TCM in order to get rid of the wrench for 35's (I think your tires are 33s though). Is the right? I'm not seeing anyone else w/ success on tires greater than 33's. I have 35's (285/75R18) and have a Hypertech Programmer/Tuner (Part #3050) on order. Should I expect to need to get a forscan as well after updating tire size via the tuner? Or should the tune just work? I assume I'm going to have to deal with an incorrect speedometer and gearing...

I did get the wrench. But using forscan to have the TCM (transmission control module) relearn the vehicle cleared that for me.

However, there is a threshold of how large (in MM) you can input for tire size where the wrench will stay on. A custom tune (ECM/TCM) would fix that.

Also play with the mm tire size there, I found that I only needed to add the size in MM that my new tires added (+12MM for mine) while "under the vehicle's load". My speedometer was spot on with Waze after.

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To date no wrench/DTCs have been thrown.

Tires size LT285/65R18 wheels -12mm offset 18”x9”

 

[DWs-TTEB]

Thanks for the updates, this gives me hope, but I'm still a little confused. It sounds like you added a custom tune and then used forscan to relearn/reset the TCM in order to get rid of the wrench for 35's (I think your tires are 33s though). Is the right? I'm not seeing anyone else w/ success on tires greater than 33's. I have 35's (285/75R18) and have a Hypertech Programmer/Tuner (Part #3050) on order. Should I expect to need to get a forscan as well after updating tire size via the tuner? Or should the tune just work? I assume I'm going to have to deal with an incorrect speedometer and gearing...



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My tires are 33” off the truck & 32” on the truck. Most aftermarket tuners allow you to adjust the tire size. However, I’m not sure about the tuner you bought for this model. I know Forscan will all you to mod the tire size. A custom tune from say 5Star or ZFG etc. will do it as long as you tell them your current mods. ForScan allows you to have the vehicle relearn the tire size axle ratios etc. with the ECM/TCM relearn function. The ForScan OBDII reader cost $15 on Amazon and the ForScan license cost $10. YMMV.

 

[1970Maverick]

here's a good site that can help with choosing a tire size. It lets you compare OEM size to any other size you may be considering.
https://tiresize.com/

 

[Aaadd0826]

I recently installed the Readylift 3/2 lift along with the recommended 285/75r18 tires on factory wheels. Those tires are actually a little too big and were rubbing in the rear before doing some trimming of the liner. The fronts just barely clear, and rub slightly in the right circumstances. I should've went smaller actually, and I wasn't too impressed with the recommendation and instructions from Readylift. I did achieve the clearance I was looking for though.

Now the problem . . .

After installing the tires I planned on adjusting the tire size through Forscan as I successfully did on my F250. I assumed I would be able to go up a little bit on tire size without issues, but I found that any value I put in other than the value for the factory size tires would cause wrench icon to appear in the dash. I went back and forth several times until I found the right value to accurately calibrate my speedometer to the bigger tires, but now even if I change the values back to stock the warning won't go away.

Has anybody found a successful way to calibrate after installing bigger tires without a DTC? And apparently there is not a range of sizes to work within without throwing a code like in the pickups?

Thanks!

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I have 285/75r18 on mine with little trimming

 

[Aaadd0826]

I have 285/75r18 on mine with little trimming

 

[UnrulyBeardsman]

Thts what happens when you mess with stock suspension. Pulls rear wheels forward and both driver and passenger wheels INTO the wheel well

New Rough Country kit fixes that issue with trailing arm hardware!