so today I was servicing my dads 97 diesel and found excessive play in the front driveshaft. the front u-joint isn't wasted but it is on the oust. but additionally the most play was coming from the center of the drive shaft where the back half and the front half are splined together and then covered with the rubber boot. my question is, can i remove that boot shoot a bunch of grease in there or am I looking at replacing the whole driveshaft? i'm 90 percent certain that replacing the front u-joint alone will not solve the problem. can i order from spicer direct or do i have to do it through an axle shop?