The Ford Bronco and Jeep Wrangler are two SUVs with a singular mission: Providing extreme off-road performance straight from the manufacturer. And in both cases, those automakers go to great lengths to boost their ride's trail credibility with high-performance suspensions, huge wheels, robust skid plates, etc. Honestly, it's the kind of hardware you can get on a fair number of SUVs, trucks, and even crossovers. What you can't get anywhere else is a manual transfer case. The Wrangler and Bronco are currently
the only vehicles for sale in the United States to offer that.
Why does it matter? The transfer case is what splits engine power so it can go to a second set of wheels and allow a vehicle to move from two- to four-wheel drive. The ones in the Bronco and Wrangler have two speeds, allowing for two sets of gear ratios, including a low gear for off the beaten path. That's an important difference from all-wheel drive, which typically only has one gear ratio available.
In a two-speed setup, the "regular" ratio might be, for instance, 1:1, meaning that the transfer-case output shaft spins at the same speed as the main drive shaft. Moving the transfer case into its low range reduces the ratio to 4:1 so that it takes four revolutions of the drive shaft to get the transfer-case shaft to revolve once. The result is significantly more torque for low-speed trail maneuvers — as long as you know when to replace the transfer case fluid.
The Ford Bronco's Manual Transfer Cases
First off, to avoid any impression of favoritism, we're just doing this alphabetically. That means opening with the Ford Bronco, which can conquer off-roadeo adventure rides and more by offering a pair of transfer cases with manual modes. The standard system is a part-time two-speed transfer case paired with a seven-speed manual transmission, while a full-time manual transfer case is part of Ford's advanced 4WD system and matched with a 10-speed automatic. Also notable here are their lowest gear ratios: The part-time system provides a 2.72:1 low range, and the full-time system lowers that to 3.06:1.
Operation is easy, too. There are three basic settings: 2H (2WD High), 4H (4WD High), and 4L (4WD Low), with some Broncos further equipped with an automatic 4WD High capability. Keeping in mind this is a two-speed transfer case, 2H and 4H lock the Bronco's drivetrain into two- or four-wheel drive, with the high gear for normal driving. Switching to 4L takes advantage of the transfer case's low gear for low-speed off-roading. Keep in mind that 4L requires you to stop the Bronco, and put it in neutral before shifting the transfer case into low. (The automatic 4A setting uses the high transfer-case gear for on-demand 4WD, allowing the vehicle to go from 2WD to 4WD as needed).
The Jeep Wrangler's Manual Transfer Cases
Jeep also lets you choose from two manual transfer cases as you live the American dream, ensuring there's one for every Wrangler trim level except the 392 Final Edition. Technically, each is a version of the NV241, with one, the NV241 OR, getting enhanced for off-road use. They're built by a company called New Venture Gear, which is now owned by Magna but originated as a joint venture between Chrysler and General Motors.
The Wrangler Sport, Sport S, and Sahara comes standard with the Command-Trac system that relies on an NV241, while the Rubicon packs the Rock-Trac NV241 OR. Both are part-time, two-speed setups with 2WD High, 4WD High, and 4WD Low driving modes, the crucial difference being their low-range gear ratios. Wranglers with Command-Trac get a ratio of 2.72:1, and those with Rock-Trac leveraging a 4:1 ratio. Remember, the higher that first number, the more times the drive shaft has to revolve to turn the wheels and the low-speed torque is available.
Something else to keep in mind, for both the Wrangler and the Bronco, is that these SUVs are additionally available with different axle ratios that allow them to effectively lower the gear ratios even more. The so-called crawl ratio for a Jeep Wrangler can be as low as 100:1, which compares to the Bronco's 94.75:1. With numbers so close, you can make a great case for off-road domination in either SUV.
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