Using Strings [Text] in one of those queries is a little more tricky because you have to pass double-quotes on either side of the string [DriverName]:
Try copying the following into your code and see if it works.
Code:
strSql = "INSERT INTO Tasks (TyreNumber,CurrentKm,TruckNumber,DriverName) "strSql = strSql & "VALUES (" & NewTyre & "," & Me.CurrentKM & "," & Me.TruckNumber & "," & "'" & Me.DriverName & "'" & "); "
DoCmd.RunSQL strSql
Also - here's a web site that belongs to pbaldy - a regular helper on this site.
There is some information there that I have found very handy.
http://www.baldyweb.com/