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Discussion Starter #1
Looking to pick up some new tires for the sts-v. I have 20 inch rims and I'm wondering what the widest tire size is I could go with for the back. Would 305's fit? I'm currently running 285s

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Was thinking some 305 35 20s or 305 30 20s? Thoughts?
 

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Width of the wheel will dictate the width of the tire. 305/30R20 need a 10.5" wide wheel . .

A 305/35R20 is too tall
 

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2006 STS-V and 2007 STS-V The Murdalac
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275/35 and 305/35 front and rear works. The rears are pretty tall and you have to have perfect offset and 10.5" width to the wheels for it to fit. Mine are flush with the fender and extremely close to the frame on the inside.

265/35 and 295/35 will also work if you have 10" rear wheels.
 

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To me it's worthwhile asking tirerack and Michelin the question.I was thinking 305. on my new Shelby but both places said I'd run the Risk of breaking the bead at speed and lose the car. The next thing you'd know is the insure r finds out and you wont get coverage if you blow a tire out and wreck because you had an unsafe tire/wheel combo
 

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Discussion Starter #8
Ended up going with a 295 30 20 general uhp exclaims. Got them for a great price so I couldn't pass it up. $300 canadian and they are brand new.
 

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Are your front tires 265/35 or 265/30? You will have trouble with the traction control if your front tires are the same diameter or taller than the rear.
 

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Too WIDE, you mean...
No, I do mean too tall . . a 305/35R20 I feel it is too tall at 28.3" tall . . compared to the proper overall tire height of 27.7"


Now granted 305/30R20 is only 27.2" tall, thus a little too short . . . the trick is to get over all tire heights FRONT and REAR as close to complimentary to OEM so as not to disrupt the traction control and stabilitac computer,
 

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No, I do mean too tall . . a 305/35R20 I feel it is too tall at 28.3" tall . . compared to the proper overall tire height of 27.7"


Now granted 305/30R20 is only 27.2" tall, thus a little too short . . . the trick is to get over all tire heights FRONT and REAR as close to complimentary to OEM so as not to disrupt the traction control and stabilitac computer,
305/35s work with 275/35, that's what I run. They are taller than I would like and I'll probably do a 275/30 and 305/30 next time but they maintain the correct diameter differential to allow the traction and stability control to work properly.

If you are going with the same size rim on all four corners you need to use the same aspect ratio tires with the rears being wider and thus taller than the fronts. 265/35 and 295/30 are not going to work together. The TC will kick on constantly and you'll have to shut it off every time you drive the car.
 

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Discussion Starter #12
305/35s work with 275/35, that's what I run. They are taller than I would like and I'll probably do a 275/30 and 305/30 next time but they maintain the correct diameter differential to allow the traction and stability control to work properly.

If you are going with the same size rim on all four corners you need to use the same aspect ratio tires with the rears being wider and thus taller than the fronts. 265/35 and 295/30 are not going to work together. The TC will kick on constantly and you'll have to shut it off every time you drive the car.
Funny you say that because I have that issue now lol. When I bought the car the guy told me with the summer rims I have to turn off traction control at anything over 100. Whenever I get on the hwy I shut it off or it will keep engaging. I figured it had to do with tire dimensions being off with the 20's all around. I need new front tires as well so what size should I go with?
 
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