Dual Range^® Auxiliary Transmissions

History
In 1982 when the decision was made to take an analytical look at the RV'ers towing problems, it didn't take long to realize what the industry really needed was a 2-speed axle. And quite honestly, that still holds true today. But it soon became apparent that with all the different vehicle applications and rear axle combinations required, plus the difficulty of this type of installation, the idea would be both impractical and outrageously expensive.

But what about a 2-speed that didn't have to be installed in the rear axle? This would allow one basic gear box, with the various applications handled with relatively inexpensive adapters. And now, the installation could be handled by almost any knowledgeable service center. The results? the birth of the patented Dual Range Auxiliary Transmission.

Why A 2-Speed?
Since the late 70's the large majority of RV towing has been done with 1/2 ton - 1 ton truck type vehicles; most are equipped with automatic transmissions. With towing weights as high as 12,000-15,000 lbs. there is no way, especially with the horsepower available, to have enough gearing for low speed pulling and still be able to cruise economically at interstate speeds. By selecting the proper Dual Range to complement your existing gear ratios, you can in fact enjoy both.  Low speed power and high speed economy.

How To Select Your Dual Range
If you have plenty of low speed power and you need high speed help (this is becoming increasingly rare), then you would simply add the Dual Range with the higher gearing (overdrive). If you are OK on the road at high speeds, but just don't have enough power when fully loaded then you need to add the underdrive ratios. Our technical people can help you make the decision for the best possible choice. With the proper Dual Range added to your vehicle you will now have both low speed and high speed help available at your finger tip.

How To Use The Dual Range
It's really very simple. At the flip of a switch, you can select a high speed ratio for highway cruising or solo driving, or you can select a low range for highway towing, city driving, or mountain terrain. Shifting back and forth from high range to low range can be done at any speed (shift-on-the-fly). Of course, if you are parking your trailer for the season, you may choose to leave the Dual Range in the high speed mode until you are towing again.

Factory Overdrives
Within the last few years, the automotive factories have begun to offer overdrive transmissions as standard equipment. While they are some help to the people using their trucks like Buicks, they are completely useless for towing. In fact, most factories prohibit towing in the overdrive position. But, by adding the low speed version of the Dual Range (underdrive), the factory transmission becomes a real pleasure to use. Not only do you gain the pulling power so useful for towing, you're actually able to use that power in the factory overdrive mode! No one else can offer that feature in the RV industry.

Applications Available
Class 'A' Motor Homes; the very popular Class 'C' version of the same; Fifth Wheel and Travel Trailers; Three and Four Speed Automatics; Four, Five, and Six Speed Standard Transmissions: We've Got Them All! And we are adding new popular applications as soon as they become part of the towing world.