Its worth it to do it yourself. I spend more than $31 but it is worth it to me to know it was done right. I lube the rear drive shaft every 5k with M1 synthetic grease and you would be surprised at how much grease the u-joints take to push out the old and refresh to the new (3-4 pumps). The slip yoke only gets a pump or two. I use an M1 filter with Royal Purple 5w-30 oil, clean my k&n air filter, check the cabin air filter, grease the drive shahts, and occassionally clean the throttle body. Rig runs like a champ and gets decent MPG. I do take it to discount tire every 5k to have a 5 tire rotation, BFG ATs have less than half wear at 25k.