whats the amount of time a uniball should last on a truck thats not driven hard mostly cruised in the dirt but driven everyday on the pavement? i have the CST upper uniball arms and i put uniballs in the lower arms and all four feel different. the uppers feel pretty rtight and the lowers are a little looser. one actually needs replacing it moves in the cup. i have had these on for less then a year and i thought they would at least last a year.