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2015 mkc reserve, 2.0 fwd
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Discussion Starter · #1 ·
Greetings all,
My 2015 MKC has the 19" rims with 235/45/19 tires on it. I for one, don't like low profile tires, and prefer to have more rubber between the rim and the road. Anyone have any experience going to a 235/50/19 tire which will give 5% more height. If I'm not mistaken, a 20" wheel is an option on the older MKCs and therefore the clearances should be already built in to allow for this, but I'm finding no google searches that are definitive. Even most of the tire local Belle tire and Discount tire boys have misleading answers on this issue. I understand that the new tire size should be programmed into the vehicle to assure mileage and speedo accuracy, and I can do that, but still want to be sure I'm not creating any other problems by going with a slightly higher profile tire. Michigan potholes eat up low profile tire rims.
Thanks for any input.
 

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So what I have noticed is you will get a recurring error code if you recode the BCM/PCM for the tire size changes, so I reverted back to factory coded size. I have run successfully with a 29" tire with no (maybe just a little) tire rub. This was a 255/45/20

In your case on 19" wheels a 235/55/19 would be 29.2 in
and 230/55/19 would be 29


I don't know if a 230 would mount okay or not! Maybe someone else can answer that part of the question.
 

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2015 mkc reserve, 2.0 fwd
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Discussion Starter · #3 ·
Hey CB,,,,, 235 is 235mm or 9.25 inches of tread width. 45 is 45% of that or 4.16 inches of tire height. A 19 inch wheel with 2 x 4.16 inch of tire comes out to 27.32 overall height. Staying with 235 or 9.25 inches of tread with and going to a 50 or 50% tire height (ground to rim) is 19 inches plus 9.25 or total of 28.25 inches overall height. I think I'm calculating it right,,,,gaining just under a full inch of height on each tire or added less than 1/2 inch of potential interference from wheel center . I'm thinking it should work out fine and not cause any driving problems. The BCM issue you talk about, is that an error when you plug into your obd or showing an error on your dash display when you start the car?
 

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This is what I use. Tire Size Calculator
Nice job on the math though, I didn't know how to do that!! When I try math, I make simple errors 馃槖

The error shows up within the obd scan. It did not ever show an error light on the dash.

One benefit I noticed though was I am pretty sure the extra 1" of tire increased my fuel mileage. Could be wrong... as I said before. I make simple errors!
 

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2015 mkc reserve, 2.0 fwd
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Discussion Starter · #5 ·
Don't we all on the math errors, but I'm pretty sure that by keeping the same 235mm tires and 19" rims, I will gain only 1/2 inch per side (slightly less actually, from the center of the wheel) and that should not give me any interference problems given that some mkcs use 20 inch wheels with no rubbing reported. Most tire retailers say shouldn't do that though, because the factory doesn't recommend it. Well, there's a lotta things as you know, the factory frowns on. Thanks for the input and look forward to trying your latest mod to hopefully eliminated my collision warning. I road trip the mkc much more now that I've got manual cruise working like it should thanks to you.
 

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Have you had any alignment troubles?

I went bigger side walls from 235 50 18 to 235 55 18 and the dealer is blaming my tires .. my car ia pulling to the right.
 

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Have you had any alignment troubles?

I went bigger side walls from 235 50 18 to 235 55 18 and the dealer is blaming my tires .. my car ia pulling to the right.
No it鈥檚 physically impossible for a tire to change the alignment. Alignment consists of caster which is where the top strut mounts to lower ball joints if you looked across the vehicle from left to right, camber is the same strut mount to lower ball joint if you looked front to back down the vehicle, and toe is your wheel turning in relation to the opposite wheel and to straight in line with the car. All those points of alignment have nothing to do with what tire you have on your car. There are also other alignment values which also do not have anything to do with the tires, the only thing tires will do is either raise or lower your ride height and change your rotations per mile which changes your speedometer
 
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