Planning on Running 255/40/19 on stock rear 19" wheels

agustinjr1243

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Hi Everyone! Im new to this forum and wondering if anyone has ran a 40 sidewall tire on RWD and did you have rubbing issues?
 
You will go from a 0.1" / 0.4% difference in height, to a 0.9" / 3.4% difference. This would not be ideal on an AWD car, but is less of an issue for RWD. They should fit fine, and your speedometer will read a couple mph low, only thing I'm not sure about is if this will confuse the traction/stability control.

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You will go from a 0.1" / 0.4% difference in height, to a 0.9" / 3.4% difference. This would not be ideal on an AWD car, but is less of an issue for RWD. They should fit fine, and your speedometer will read a couple mph low, only thing I'm not sure about is if this will confuse the traction/stability control.
Sorry i should have stated that the stock tire size on the rear is 255/35/19 the only thing that would change would be the sidewall from a 35 to 40.
 
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Sorry i should have stated that the stock tire size on the rear is 255/35/19 the only thing that would change would be the sidewall from a 35 to 40.
That is an OD difference of 26mm, or over an inch difference. It will probably look pretty good if you are still running 225/40 in front. And no trouble at all on RWD operationally - as long as you remember the odometer difference mentioned. At least the discrepancy is on the safe side. I bet you won't rub unless you really pound a bouncy curve. The stock wheel has an offset of 46.5 and the 255/35 has lots of clearance. A half inch of clearance lost on a 255/40 shouldn't matter.
 
Sorry i should have stated that the stock tire size on the rear is 255/35/19 the only thing that would change would be the sidewall from a 35 to 40.
Right, if you look at my screenshots, they compare stock front vs. stock rear, and then stock front vs. your 40 profile rear. The third column in each is the front/rear difference. You could also plug in stock rear (35) vs. proposed rear (40) and see the direct comparison (it will be the same as comparing column 2 from each screenshot above).
 
From interior to exterior to high performance - everything you need for your Stinger awaits you...
I’d go 235/40 front and 265/35 rears. Been running that way for 2 years now and love it.
 
I can speak from experience, if you want to mismatch front and rear from the factory sizes you will need to disable TC everytime you drive the car or else you will have lots of fun negotiating a round about!

Follow THOMBY's chart above ^^^

I went with these and the rolling dia looks absolutely identical and is also much smoother and has better traction than the factory offering. :thumbup:

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I drive a Stinger GT AWD so rolling dia need to be fairly close. Stock 225/40/19 fronts and 255/35/19 rears means a sidewall difference of 0,75mm (89,25mm rear, 90mm fronts) and this small difference seems to be ok with the AWD sysstem.
So, I'm wondering if someone is riding 225/45/19 fronts and 255/40/19 rears?? Would be same sidewall difference (0,75mm) at 101,25mm fronts and 102mm rear sidewalls...
Would love to know if someone is riding w this setup. Should nicely fill up wheel wells and give it a slightly plusher/quieter ride. I drive on gravel roads w pot holes n stuff for a couple weeks every summer and the stock tires are a little gnarly on roads like that.
 
Haven't noticed anyone specifically choosing that sizing. But you are right to maintain equal OD front and rear with AWD. The actual OD change over all shouldn't matter, other than throwing off your indicated speed. I have no idea how much, as that is an equation and I am not friendly with math. But I would guess in the 2 MPH off range at freeway speeds.
 
Haven't noticed anyone specifically choosing that sizing. But you are right to maintain equal OD front and rear with AWD. The actual OD change over all shouldn't matter, other than throwing off your indicated speed. I have no idea how much, as that is an equation and I am not friendly with math. But I would guess in the 2 MPH off range at freeway speeds.
Thx Snicklefritz! Yeah sure a slight change to speed "accuracy" is bound to happen but not a big deal to me. Of course car will sit about 12 mm/0,5 inch higher but even that shouldnt be too visible...
 
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From interior to exterior to high performance - everything you need for your Stinger awaits you...
Thx Snicklefritz! Yeah sure a slight change to speed "accuracy" is bound to happen but not a big deal to me. Of course car will sit about 12 mm/0,5 inch higher but even that shouldnt be too visible...
Or actually car will be closer to just about 10 mm higher, not 12
 
Or actually car will be closer to just about 10 mm higher, not 12
I get 0.9" taller in front, 1.0" taller in rear, and a perfect match (vs. 0.1" stock difference).

The car will sit 0.5" higher (the half diameter from ground to center of wheel), and the gap to the fender will be 0.5" closer (the half diameter from center of wheel to top).

Circumference will be 3.4% higher front, 3.9% higher rear, ie speedometer will read that much lower.

Stock: Tire Size Calculator
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Modified:
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So will this work because I am honestly about to try this on some aftermarket wheels.
225/45/19
255/40/19
 
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