[KTL]

They are shipped ready to install. But unfortunately the grease they use is cheap crap. This is going to sound stupid but here goes anyway. I would suggest pulling back the boots (or remove the inner CV) and clean out the grease so you can replace it with a high quality synthetic grease that will last. The reason most CVs fail is inadequate lubrication and that's primarily on account of the quality of grease. Use a high quality synthetic grease from the start and you'll not have to mess with them again for a long long time.