The Crump surname has two possible origins and a long line throughout the history of England.
A post on Family Tree DNA states:
We have seen quite a bit of published information on the CRUMP family over the last hundred years, however, it is known that some of it is in error. With the introduction of the Internet and personal computers, and numerous family lineage sites, much of this misinformation is being passed on as fact by many who do not take the time to research and just copy and past what is currently available without checking the sourcing or lack of sourcing of the information that they are relying upon.
The Y-DNA testing that has been done to date within the Crump surname project has revealed that there are AT LEAST seven totally unrelated Crump lines in America. This lends creditability to the theory that the Crump surname has originated in various ways other than just that of a physical characteristic, possibly a trade or geographic location. The seven distinct Haplogroups to date, means that even the Deepest Ethnic Origins are not even the same for all carrying the surname of Crump or its derivations.
Surnames only came into use around the 11th century to the end of the 16th century. Having identified seven different Haplogroups, with surely more yet to be identified makes it certain that there is not one progenitor of the surname Crump and variations such as Crompe, Crumpe, Crampe, Kumpp, Kramm and others.