randy,
The brand/model tire will have more of an effect on traction than the size. The worst tire for traction in one that is over 75% worn. Tires with this many heat cycles tend to get very hard and loss a lot of their grip. The KD's are your best bet even though they get pretty noisey as they get worn out. I would recommend a 275/40R17 G-Force KD. This assumes you have at least a 40mm offset. If you also need a recommendation for the front, let me know what size and offset wheel you have on the front.
Later, Steve