Sales of General Motors' Two Mode hybrid SUVs started slowly this year. But as cities look to make their mass transit systems more environmentally friendly, GM has had increasing success selling the Two Mode system for use in diesel buses.
More than 1,000 buses powered by the GM-Allison Two Mode transmission have been delivered to transit systems. Late last year, three transit authorities agreed to buy a combined 1,700 more.
"Hybrid is an incredible tool for transit authorities," said Tim Grewe, GM's chief rear-wheel-drive Two Mode engineer.
First used on bus fleets in 2004, the Two Mode system allows transit authorities to decrease emissions, improve fuel economy and lower maintenance costs. Cities from Kelowna, British Columbia, to Istanbul, Turkey, have purchased buses with the transmission.
The hybrid technology is called Two Mode because it offers hybrid efficiency in both city and highway driving.