You Cannot
(Should be a holder of a license for light vehicles (only B and B1 vehicle classes) for a minimum of 2 years)
Extension of the driving license for heavy vehicles.
Should be a holder of a license for light vehicles (only B and B1 vehicle classes) for a minimum of 2 years prior to the date of application.
To obtain a license for light motor bus and motor lorry category the minimum height should be 4 feet 10 inches. A minimum height of 5 feet is required to obtain a licence for Motor bus and motor lorry category.
It is possible to register and face the written test on completion of 20 years of age.
In the event of passing the written test, a learners’ permit is issued for maximum period up to 18 months.
Holder of such permit can practice driving.
21 years of age has to be completed to face the practical test and a minimum of 3 months should have passed since obtaining the learners’ permit.
It is compulsory for the applicant to face the practical test and pass it.
Aptitude Medical Certificate obtained from the National Transport Medical Institution within a period not exceeding 6 months.
http://www.motortraffic.gov.lk/web/...&id=83:new-driving-license&Itemid=140&lang=en