Replacing tires on an '04

[Mello Yello]

I have an '04 ZQ8 that has to have the worst tires I have ever driven on! When the least amount of dampness gets on the roads my truck is terrible starting AND stopping! I have been told that the Continental Contact AS tires that were OEM when my truck was built are "inappropriate" for a sport truck! I plan to get rid of these tires soon, and want to use wider tires! What I would like to do is go from the stock 235/50/17s to Kumho ASX 255/45/17s! I realize that there will be a difference in the speedometer, what other effects of this change can I expect? I have also been told that I can't make any tire size changes as I would "screw up" the ABS and something in the transmission! Is anyone familiar with the Kumho ASX tire and want to voice an opinion! ANY comment on this switch would be appreciated! Any suggestions are welcomed!

[Philo]

Circumference is everything. Measure one of your tires, then go shopping. Within 2 to 3 percent should be OK. Width doesn't matter.