Taller Tires & Cruise Control

[MidwayJ]

I'm aware some here have had issues with cruise control not working when running on taller than stock tires. Some have suggested staying as close to stock diameters as possible, and no more than 3% more.

Questions: Is it the diameter of the front tires or the rear that impacts cruise control? Could moving to a smaller diameter tire vs. stock cause the same problem?

The reason I ask is my PP car came with 255/40r19 front (27.0" diameter) and 275/40r19 rear (27.7" diameter). If I get a square setup of 20x10 wheels with 285/35r20 tires (27.9" diameter), the front diameter goes up by 3.3% but the rear diameter only increases by 0.7%. If it's the rear that matters I wouldn't be concerned but I'd be hesitant to go that route if it's the front that matters.

If I go with 19x10 square with 285/35r19 tires (26.9" diameter), the front diameter goes down by only 0.4% but the rear decreases by 2.9%. Not sure if smaller diameter than stock can cause issues as well.

My understanding is the rear tire size is what impacts the speedometer, so it would be nice if that's what impacts the cruise control as well.

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[Andy Feuer]

I'm aware some here have had issues with cruise control not working when running on taller than stock tires. Some have suggested staying as close to stock diameters as possible, and no more than 3% more.

Questions: Is it the diameter of the front tires or the rear that impacts cruise control? Could moving to a smaller diameter tire vs. stock cause the same problem?

The reason I ask is my PP car came with 255/40r19 front (27.0" diameter) and 275/40r19 rear (27.7" diameter). If I get a square setup of 20x10 wheels with 285/35r20 tires (27.9" diameter), the front diameter goes up by 3.3% but the rear diameter only increases by 0.7%. If it's the rear that matters I wouldn't be concerned but I'd be hesitant to go that route if it's the front that matters.

If I go with 19x10 square with 285/35r19 tires (26.9" diameter), the front diameter goes down by only 0.4% but the rear decreases by 2.9%. Not sure if smaller diameter than stock can cause issues as well.

My understanding is the rear tire size is what impacts the speedometer, so it would be nice if that's what impacts the cruise control as well.

I have the EXACT same question, and have asked as well but most just reply that "they don't use cruise". I just bought 20" rims, but I'm waiting to hear what I can run and not have a problem. I was hoping to go 285/35 Fr, and 305/35 in the rear.

 

[DevilDog]

Same here. It would be nice if the sponsors on this site who sell wheel/tire combinations would chime in with their expertise. You'd think they might receive feedback from customers who've had issues.

 

[robvas]

Who's actually having this issue?

 

[Andy Feuer]

Who's actually having this issue?

There's a whole thread about it.

 

[Dark Sprite]

Are you able to edit wheel diameter in FORScan to eradicate the issue?

How does Ford configure it between non-PP, PP and DH HP?

 

[Andy Feuer]

Are you able to edit wheel diameter in FORScan to eradicate the issue?

How does Ford configure it between non-PP, PP and DH HP?

From what I got from the other thread, that can't fix it. Evidentially there could be 1 of 2 problems, or both.
1. The regular cruise wont work due to the RPMs being different from stock.
2. The adaptive wont work because the camera height is taller (higher).

So if anyone with 20's can try their regular cruise, and adaptive cruise we will know. It would also help to state your tire size.

 

[Ken H.]

I’m having this issue. Posted multiple times times. DH with HP. Switched to 285/35/20 (27.9”) Front & 305/35/20 (28.4”) rear. Lost Cruise control & pre-collision assist. Dealer couldn’t fix it. Ford said it was the tires affecting the windshield camera view of road. Went back stock (305/30/19 26.6” Front, 315/30/19 26.5”Rear). Problem solved. Went back to 20s with 285/30/20 (26.8) front & same 305/35/20 (28.4”) Rear. Problem back. I haven’t taken it back to dealer yet due to salted roads. Not sure if it’s the rear tires causing the problem. They are 1.9” taller than stock. Ford Customer Service said to take it back to dealer then contact them to get technical assistance. If I have to change rears, will go with 295/35/30 (0.5” taller than stock) or maybe 285/30/20 (26.8”) rear (0.3” taller).

Very confused & frustrated. No definitive expert guidance. As stated above, where are the Ford & Aftermarket engineers on this forum? Why can’t they give me a definitive answer on what we need to use to avoid this problem?
In hindsight, I wish I had stayed with th stock 19” wheels & gone with closest tire diameter match. Recent post mentioned Goodyear All Seasons in 305/30/19 & 315/30/19 that sound like the true solution. They weren’t out when I made my move and I wanted black rims instead of the Tarnished Gray stock color and Michelin All Seasons. Should have had them painted!

 

[Ken H.]

From what I got from the other thread, that can't fix it. Evidentially there could be 1 of 2 problems, or both.
1. The regular cruise wont work due to the RPMs being different from stock.
2. The adaptive wont work because the camera height is taller (higher).

So if anyone with 20's can try their regular cruise, and adaptive cruise we will know. It would also help to state your tire size.

Dealer told me that if you have the adaptive cruise option, still can’t just switch to standard cruise in settings because that is dependent on camera input also. Not sure if problem exists in cars that have only Standard Cruise.

 

[Sofa King]

I guess I need to try mine... stock F & R were 27", now have 27.3 in front and 28.1 in rear... though I did actually change my tire size using a Procal 4 tool. My theory is, if the tire size is set correctly it should all just work... we will see.

 

[Andy Feuer]

I’m having this issue. Posted multiple times times. DH with HP. Switched to 285/35/20 (27.9”) Front & 305/35/20 (28.4”) rear. Lost Cruise control & pre-collision assist. Dealer couldn’t fix it. Ford said it was the tires affecting the windshield camera view of road. Went back stock (305/30/19 26.6” Front, 315/30/19 26.5”Rear). Problem solved. Went back to 20s with 285/30/20 (26.8) front & same 305/35/20 (28.4”) Rear. Problem back. I haven’t taken it back to dealer yet due to salted roads. Not sure if it’s the rear tires causing the problem. They are 1.9” taller than stock. Ford Customer Service said to take it back to dealer then contact them to get technical assistance. If I have to change rears, will go with 295/35/30 (0.5” taller than stock) or maybe 285/30/20 (26.8”) rear (0.3” taller).

Very confused & frustrated. No definitive expert guidance. As stated above, where are the Ford & Aftermarket engineers on this forum? Why can’t they give me a definitive answer on what we need to use to avoid this problem?
In hindsight, I wish I had stayed with th stock 19” wheels & gone with closest tire diameter match. Recent post mentioned Goodyear All Seasons in 305/30/19 & 315/30/19 that sound like the true solution. They weren’t out when I made my move and I wanted black rims instead of the Tarnished Gray stock color and Michelin All Seasons. Should have had them painted!

Yeah Ken. I believe you were one of the guys from the last post. I already bought expensive 20" rims but haven't opened them yet. When I bought them from Vibe (who's a sponsor here), he didn't say anything about a potential problem.

 

[Ken H.]

I didn’t see any posts before I made my move. But, I was new to the Forum & admit I hadn’t read everything. Then after I had my problem & posted, I’ve seen others say they are having problems. Surely there are many others who have changed wheels & tires but I’m perplexed why it’s not a universal problem.
I need to drive to Florida & wanted to take the DH but can’t see 14 hrs without cruise control. Bummer.

 

[Ken H.]

Forescan is probably the ultimate fix, but I’m just a little intimidated to change things in the computer & my Windows laptop sucks.

 

[Dark Sprite]

I’m having this issue. Posted multiple times times. DH with HP. Switched to 285/35/20 (27.9”) Front & 305/35/20 (28.4”) rear. Lost Cruise control & pre-collision assist. Dealer couldn’t fix it. Ford said it was the tires affecting the windshield camera view of road. Went back stock (305/30/19 26.6” Front, 315/30/19 26.5”Rear). Problem solved. Went back to 20s with 285/30/20 (26.8) front & same 305/35/20 (28.4”) Rear. Problem back. I haven’t taken it back to dealer yet due to salted roads. Not sure if it’s the rear tires causing the problem. They are 1.9” taller than stock. Ford Customer Service said to take it back to dealer then contact them to get technical assistance. If I have to change rears, will go with 295/35/30 (0.5” taller than stock) or maybe 285/30/20 (26.8”) rear (0.3” taller).

Very confused & frustrated. No definitive expert guidance. As stated above, where are the Ford & Aftermarket engineers on this forum? Why can’t they give me a definitive answer on what we need to use to avoid this problem?
In hindsight, I wish I had stayed with th stock 19” wheels & gone with closest tire diameter match. Recent post mentioned Goodyear All Seasons in 305/30/19 & 315/30/19 that sound like the true solution. They weren’t out when I made my move and I wanted black rims instead of the Tarnished Gray stock color and Michelin All Seasons. Should have had them painted!

If you wouldn’t mind the hassle… perhaps you could try mixing the stock fronts and aftermarket rears and see if the problem exists? Not as a permanent solution obviously but just to see whether it is the fronts or rears that cause the issue.

 

[Aggie1999]

I have the EXACT same question, and have asked as well but most just reply that "they don't use cruise". I just bought 20" rims, but I'm waiting to hear what I can run and not have a problem. I was hoping to go 285/35 Fr, and 305/35 in the rear.

That is my exact setup and I don't have any issues using my Cruise Control, not that I use it much.

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