Discovered i went over the time limit on scheduled maintenance for coolant change though way short (25k) of the mileage recommendation. Am the original owner of the 2002 Sierra. Should i go ahead and change the coolant....or since the mileage is so low will i be good to go for awhile.....any thoughts appreciated about mileage/time affect on Dex-Cool? Have i already voided my extended factory warranty?

Change the coolant out. Time is more of an enemy than miles.

Thanks for the reply...already accomplished. Would have thought mileage was the more critical of the two.....