which rear tires should i get?

JARblue

Saying you will have problems is a bit extreme. Depending on the tires and their condition, you may or may not have stability issues. In general, this is not recommended, but it's not necessarily unsafe. I changed out my rears from OEM to Nitto Invo after <10K miles. I got over 20K on the front tires before switching all four tires to Nitto Invo the next change. They did absolutely fine, even in the rain. The biggest concern is the tread patterns cause havoc with the way that the tires shed water. The front treads could possibly make the rear tires more likely to hydroplane.

The OP is running PSS all around right now. He's looking to swap out the rears and continue running PSS in the front.

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