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2008 STS 1-SG, traded in 2005 STS4 1-SG
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Discussion Starter #1
I have a 2005 STS4 1-SG that I bought in November 2005 and it now has approximately 25,000 miles. I have experienced what I consider to be premature front tire wear and the fronts are just about done, but the rears still look good. The original tires are Michelin P235/50R18 front & P255/45R18 rear.
When I first noticed the tread wear (which is edge wear, both inner and outer) I bumped the standard tire pressure (30 psi F&R) to 32 psi front and 30 psi rear. This helped some, but it was too late.
I notice that the 2006 STS-V has P255/45R18 Pirellis on the front and that the 2006 STS 1-SG (from the Cadillac website) has P255/45R18 Michelins all around (I think).
I assume that tire clearance is not a problem with the larger tires on the front, although the larger contact patch could increase hydroplaning.
Here's the questions...
Does anyone know of any clearance issues with the larger tire size mounted on the front?
Since my car is AWD, is the rolling circumference equal between the P235/50R18 & P255/45R18 or is there a gear ratio in the transfer case on the AWD? I don't want to compound the problem if there is a gear ratio between FWD & RWD.
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