SFDC will generally do this, however, it depends on the rules surrounding your Record Type IDs.
The usual method is to let it sync, let SFDC do its thing, then in Marketo do
if Lead is XYZ, then Record Type=1940489404904x02030
and sync it.
Usually that works. But everyone's SFDC is different.
1st thing, get the SFDC ID's of your lead record types. The 15 digits ID is good enough and you can get it from the URL of the records types, when looking / editing them in SFDC setup.
In Marketo, you can set the Record type with the values before pushing the leads to SFDC. You can do this either:
- setting the field in a "record type" column in the import file
- Run a smart campaign immediately after import.