Nothing wrong with using the gridview ... you just need to get the data query right
Try this in the data source
SELECT A.Cname B.Vname, B.Vmodel, C.engineoil, C.hydraulicoil
from [customer info] A
INNER JOIN vehinfo B ON A.Cid=B.Cid
INNER JOIN [service info] C ON A.Cid=B.Cid and B.Vid=C.Vid