automatic route determination for sales order

Defined

Transportation Zone sold to party -0000000002

Shipping conditions -01

Transportation group in Material master -0001

Transportation zone ship to party - 0000000003

Assignment made -

Dep country zone -0000000002

Dest country zone -0000000003

Sc -01

Transportaion group -0001

route -zroad

departure zone and destination zone is assigned to respective customer masters. and above assignment is made in IMG for route determination for order. But when i create the sales order route is not getting determined..i wnet to most of the threads in this form..but could not find a thread for route determination for sales order