[Britwrench]

If the rack boots are leaking oil then the rack is leaking internally.
The boots should be, but rarely are, dry inside. Replacing the boots will not cure any leaks, it just allows oil to build up inside. Minimal amount on oil in the boot is ok, just keep an eye on the level and amount of oil in the boots. Basically, if there is a lot of oil in the boots you need to reseal or replace the rack.