I've got a CV boot ona Focus estate come adrift, fell off after reassembling the front after a wheel beraing swap. Done maybe 300 miles and ejected a lot of grease, and also over gravelly roads in the wet - not ideal but that's why you do weekly checks to see this sort of thing I suppose.
How to fix? Clean the join in situ and repack with CV grease? Or worth pulling off the car, swilling all the gunk out with diesel and regrease or god forbid split the joint apart and do it that way? The boot holds in place and hasnt yet come off after some enthusiastic full lcok tunrs so I think that will at least hold OK