Speedometer calibration after lift/tires

[leadfarmer]

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!

 

[16plati]

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!

View attachment 30718 View attachment 30719 View attachment 30720 View attachment 30721

Nope, need to either have an offroad shop donut or buy a calibrator and do it yourself. I highly advise going back in to Forscan and putting the stock tire size back in. Then use Forscan to clear your DTCs. If that doesn’t work you’re gonna either need to drive and guess your correct speed or have a shop do it. You’re mpg is gonna be off and you can really mess up your truck if you do it wrong

 

[16plati]

Man that rear tire being pulled forward is really accentuated in these 2018s..

 

[Black]

How far are you off?
I did not go as large as you but according to the tire calculator on tiresize.com when reading 80 mph my actual speed should be 82.7 mph.
I have tried 3 separate gps units set my cruise control at 80 and the GPS reads 80. I don’t have a GPS that breaks it down to the decimal nor does the dash display.
I rarely do highway driving so I have not even messed with it.

 

[leadfarmer]

Nope, need to either have an offroad shop donut or buy a calibrator and do it yourself. I highly advise going back in to Forscan and putting the stock tire size back in. Then use Forscan to clear your DTCs. If that doesn’t work you’re gonna either need to drive and guess your correct speed or have a shop do it. You’re mpg is gonna be off and you can really mess up your truck if you do it wrong

I was wondering if anybody has used an aftermarket calibrator with success? I know they only have a certain range they will work in on the Super Duty without a DTC. These tires are under that threshold though. And I agree, I don't really like how much the rear tire is pulled forward. That is where the rubbing issue was.

How far are you off?
I did not go as large as you but according to the tire calculator on tiresize.com when reading 80 mph my actual speed should be 82.7 mph.
I have tried 3 separate gps units set my cruise control at 80 and the GPS reads 80. I don’t have a GPS that breaks it down to the decimal nor does the dash display.
I rarely do highway driving so I have not even messed with it.

It was off about 5mph at highway/freeway speed, which is 90% of it's driving. With the value I put in, the speedometer is dead on, but I have the warning come on every time it is started. Not the best solution either way.

 

[Black]

Interesting. Guess you may be getting yourself a tune.

 

[Edwin C Aldredge]

I tried 34s and just didn’t have the clearance so I stuck with 33s. For mine, the speedometer difference was negligible so I haven’t worried about it.

If you got a tune and an N gauge would that let you adjust it maybe?

 

[16plati]

I tried 34s and just didn’t have the clearance so I stuck with 33s. For mine, the speedometer difference was negligible so I haven’t worried about it.

If you got a tune and an N gauge would that let you adjust it maybe?

Absolutely they will calibrate your tune strategies to adjust for larger tires too

 

[sanman28]

Man that rear tire being pulled forward is really accentuated in these 2018s..

Seriously. Never noticed it that bad. I guess bc his tires are so tall.

 

[duneslider]

Nothing of real value to add but I think your expedition looks fantastic. Love the color and tire and wheel combo. Makes me want to put a little bit nicer tire on mine now.

 

[16plati]

Nothing of real value to add but I think your expedition looks fantastic. Love the color and tire and wheel combo. Makes me want to put a little bit nicer tire on mine now.

It’s crazy what a tire and wheel package can do to these trucks

 

[Grey ghost]

It looks like that rear tire should be back a couple inches,really odd looking.

 

[16plati]

It looks like that rear tire should be back a couple inches,really odd looking.

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

 

[browning4x4]

There is a forscan fix you can try. I used it on my 15 f150 when i went to 33's same tire actually. I would check out the forum and look over the document and formula. Everything seems to spot on MPH and i don't through any codes. I haven't hooked up forscan to the expy.

 

[Damian Allegree]

Hello all I thought I would share what I could with you all on this subject. I myself am working on a couple 2019 Expeditions with the same result. They are ECO Boost models. I have used Forscan, Ford Performance Programmers and I also have HP Tuners in which I am working with their tech department to find a solution. I have made all other models work from F150 and up and Mustangs as well. Seems to be something different in the Expedition TCM that is causing this. In addition I have a local Ford Tech that he himself is looking for a solution. Even with ford equipment you can not clear and TCM codes with incorrect tire size programmed. I have also tried a full relearn sequence with a Ford system and it also does not fix the issue. Pretty crazy setup for the Expedition alone I think. That Wrench that pops up is not just annoying but it actually limits the transmission in performance. Anyway I logged on to give any info I had as well as once I figure this out I will share on here. If anyone has in other recommendations please advise as between my self and a few others I have access to many tools, Ford and aftermarket. Thanks everyone.

 

[3DogRanch]

Watching this thread... I was planning on putting 295/70R18's (34") on mine at some point, but I'll wait to see how this pans out.

 

[16plati]

Watching this thread... I was planning on putting 295/70R18's (34") on mine at some point, but I'll wait to see how this pans out.

Gonna need to lift the front to clear 34s

 

[3DogRanch]

Gonna need to lift the front to clear 34s

I have a readylift 3/2 kit sitting in a box in the garage. I read the instructions and decided I'd let someone do that for me. Those plastic parts in the vacuum lockers for the front drive wheels have me spooked.

 

[16plati]

I have a readylift 3/2 kit sitting in a box in the garage. I read the instructions and decided I'd let someone do that for me. Those plastic parts in the vacuum lockers for the front drive wheels have me spooked.

You can do it without messing with those.. I bypassed that let if the instructions and was able to keep the IWE and hubs together. Ink suspension components I touched were sway bar, ball joint, spindle, UCA and LCA

 

[3DogRanch]

View media item 6879

You can do it without messing with those.. I bypassed that let if the instructions and was able to keep the IWE and hubs together. Ink suspension components I touched were sway bar, ball joint, spindle, UCA and LCA

Really? That's not much different than the Bilstein 5100 replacement I did on my Tundra. I used the top ring land on the 5100's instead of the ReadyLIFT on my Tundra and that worked out great.

Yeah, I know it's a Ford Forum, but I've done all my own work before and I really liked this truck and kept it for 12 years before buying the Expy.