2-speed rear axle

By Andy L.

Create a rear axle differential with an electronically controlled 2-speed for city and highway driving that would enable an otherwise typical overdrive transmission to achieve even great fuel efficiency.
Mark 10/09/2013
I have a 2012 Dodge Ram with 5.7 liter hemi and 410 rear gear. I can't understand why this day in age there is not a 2 speed rear end so that when you are not pulling a load you can change the rear end gear so you can get better fuel mileage around town or on the highway. I am getting 16 in town and 17 on the highway. So much for averaging 21.
Nathaniel D 12/20/2012
Absolutely! I think this is extremely useful.
Robert Walton 10/06/2011
With the advent of computer controlled transmissions for optimum power and fuel efficiency, a 2 speed axle would give the awe inspiring performance for racing/towing with the availablity of meaningful fuel efficency on the highway...seems like a no-brainer! Can't imagine this isn't a viable solution to improve fleet MPG averages to meet gov mandated improvements...