Hindustan Motors has announced an exchange offer for owners of Ambassador cars. Under the offer you can discard their old workhorses by getting Rs 35,000 discount while buying a new diesel car.Mr Amar Singh Rathore, the Country Head (sales and service) of HML, said the scheme, meant for customers in Tamil Nadu, Pondicherry and Kerala, aims to help its customers to get a fuel-efficient Ambassador while exchanging their old car, irrespective of age. Hindustan has invested about Rs 6 crore for developing this more efficient engine. This new engine adheres to the BS-III emission norms. Hindustan Motors also claims an improvement in fuel efficiency from 11 km to 16 km a litre of diesel.