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So I have a buddy with 2 brand new continental pro contact TX tires but instead of them being 275 40 19s they are 275 35 19s if I get them I will only have to pay 45 bucks for both not each but for both again they are brand new. Is there a big difference with the size?
 

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So I have a buddy with 2 brand new continental pro contact TX tires but instead of them being 275 40 19s they are 275 35 19s if I get them I will only have to pay 45 bucks for both not each but for both again they are brand new. Is there a big difference with the size?
The diameter is 4% smaller. The DSC doesn't like that and will illuminate a warning light.

https://tiresize.com/calculator/
 

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It really effects it that bad?
You said 2 wheels only. That means the wheels on one axle are 4% smaller than on the other axle therefore the smaller wheels will spin faster. The DSC will think that they are spinning out. So first it will reduce engine power and if the condition remains for couple of seconds then it will generate an error message and gets deactivated.

If you replace all 4 wheels then the DSC won't notice it but your speedometer and odometer will be off.
 

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OP,

I don't think you will have any problem. The DSC will be fine.

What you are proposing is a very slight change.

PS Your car was sold with varying tire sizes. It's no big deal.

:)
 

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A few months ago I bought a brand new set of Michelin's for my 750. One of the tires blew prematurely and Big O didn't have a replacement. They loaned me a brand new 35 profile tire which I rode on for a 100 miles, no issue. No warning light, no odometer difference, nothing. My guess you will be fine also. Good luck!
 

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His diameter difference is 4%. The DSC considers >5% speed difference as a spinning wheel so he will run into issues in no time.
 

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You said 2 wheels only. That means the wheels on one axle are 4% smaller than on the other axle therefore the smaller wheels will spin faster. The DSC will think that they are spinning out. So first it will reduce engine power and if the condition remains for couple of seconds then it will generate an error message and gets deactivated.

If you replace all 4 wheels then the DSC won't notice it but your speedometer and odometer will be off.
:thumbup:
 

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tire size diffential

Thanks guys just don't want to do something and run into bigger problems.
That's wise ... but the slight difference in rolling radius isn't likely to cause the electronics in your ride to throw a tantrum.

It's close to what would be similar if you replaced two worn out tires on the same axle and kept the other two until they also worn out. (e.g. a new tire tread depth = ~ 10/32"; worn out tire 4/32"; 6/32" = 1/5")

BUT!! Conti doesn't list that tire model in a 275/35x19 ?? If its a different size e.g. 255/35x19 the load rating would be too low for your car and could be bordering on dangerous! Might be "wiser" to get the opinion from a "qualified" tire professional (IMHO).
 

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His diameter difference is 4%. The DSC considers >5% speed difference as a spinning wheel so he will run into issues in no time.
I did it with no issues if you want, I can find my receipt and post it up or you can call a tire company. As for long term I'm insure. I did a 100 miles with ZERO issues. Good luck to you though.
 

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No reason to lie to you brotha. Once again, I only had it on for 100 miles as I was waiting for my replacement. You can call these guys and ask them yourself. The number is located, top left hand corner.
 

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One shows the original tires that I purchased and the other one shows the loaner tire they gave right after I had a premature blow out. Both the loaner and my original tires were brand new.
 

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