Jeep Wrangler Drivetrain Explained: Everything You Need to Know About Your Drivetrain

As the world's first civilian models were produced, Willys marketed their new "Jeep" as a multi-purpose vehicle. The wide variety of purposes of the Jeep has allowed it to be adopted and loved by enthusiasts worldwide for its ability to adapt to different types of terrain and driving styles. The Wrangler's ability to adapt to any terrain makes it popular with seasoned off-road pros, weekend off-roaders, and outdoorsy urbanites who need to get around town.

The Wrangler's drivetrain may be a legend, but you may not know how the pieces work together. So, we're going to get into the weeds and do our own exploring as we explain how your drivetrain works.

How Does a Transmission Work?

Jeep Wrangler owners have been known to modify their vehicles extensively, but a common complaint lies in the transmission. People either complain about having no "real" gear selection or boast of having a fantastic five-speed manual. But what is it that makes these claims? From the beginning days of the first World War, it's clear that transmissions are complex, but not all Wrangler owners know precisely how they work.

The way a manual transmission works is simple. It uses gears on two different shafts, called an input and output shaft, rotating in opposite directions so that one can add speed while the other subtracts it. This allows the engine to power the wheels no matter their speed, creating forward momentum.

The standard gear ratios for a Wrangler are 1st: 3.59; 2nd: 2.00; 3rd: 1.41; 4th: 1.00; 5th: 0.83 and reverse at 3.16, which means that if the engine is turning at 2000 rpm, the wheels will turn at 48 rpm.

There's a way to make the gears shift faster and produce more power, but it isn't done with your foot on the pedal. Instead, it comes from letting out the clutch while shifting, allowing each gear to start spinning before connecting to the next. This lets you reduce the time your engine is in a dead spot and keeps you going.

Automatic transmissions, known as "slush boxes," to some Wrangler owners, work a little differently. Instead of the clutch, they use fluid pressure to transmit power from one gear to another. This system provides variable ratios to give you smooth transitions with the correct torque and horsepower for what you’re doing.

The advantage of an automatic is that it provides the driver with more gear options than a five-speed manual but its mechanically complicated and doesn’t have the longevity of a manual.

Axels & Clutches Explained

Now, let's talk about what powers each wheel: the axles. First, of course, the front and rear axles for a Jeep Wrangler are different from one another. The rear axle has two main parts: the differential case and the axle shafts. The differential splits the power between the tires at a 50/50 ratio and is housed in the axle case. On it are different rings that house the wheel bearings that allow each wheel to rotate independently.

The rear axle also houses a ring-and-pinion that determines how fast or slow you can go. This is because the pinion gear, connected to the driveshaft, spins around fast - causing the ring-and-pinion gears that it's attached to spin slower due to gearing.

The front axle works similarly, but it has an open differential case instead of a ring-and-pinion setup. This is where the Jeep Wrangler gets some of its off-road capability; if one tire goes into a hole or mud, it doesn't lock up, and you can continue your way down whatever adventure you're on.

The Jeep Wrangler clutch is a simple setup consisting of the flywheel, pressure plate, throwout bearing, and release bearing. The system works much like an automatic transmission clutch.

The engine turns the flywheel and applies torque to the pressure plate, which presses against the clutch disc (also called a clutch plate) and transfers the torque to the transmission. When the driver presses the pedal, it pushes on a hydraulic piston that pushes down on the throwout bearing, which presses against the back of the pressure plate and separates the clutch disc from the pressure plate. This allows the transmission and engine disengagement to start the vehicle with the clutch disengaged.

Over the years and, depending on your four-wheeling adventures, axles, clutches, and things like pinion gears get worn. We have the replacement parts you need and people who can help you.

Torque Converters

Now that we've gone over what drives each wheel, let's talk about what drives the driveshafts that power it. Torque converters are crucial in your Jeep Wrangler's drivetrain, allowing a more fluid power transfer from the engine to the axle.

A Wrangler torque converter helps the vehicle move by allowing the engine to keep turning when in neutral. The Jeep Wrangler's torque converter is vital to the vehicle, but it may become damaged over time.

A torque converter has three primary parts: pump, turbine, and stator. The pump part pushes fluid in and out of the converter, which rotates to help start the vehicle. If it fails, the engine will not be able to start. The stator (a stationary part of the converter) has fins that help direct fluid flow and increase torque output. Finally, the turbine is a rotating part of the converter that helps transfer energy to the transmission.

Jeep Wranglers have two types of transmissions: the NSG 370 and the NSG 370 with a Mopar T-case shifter conversion. The torque converters for these transmissions are different as well.

When a torque converter fails, it will often produce a rattling or clanking sound when the vehicle is in neutral. This sound is especially noticeable after the vehicle has been driven for a long time or cold outside. The noise will not be there all the time. In some cases, the sound may get louder or change pitch. Of course, we can help. Drive plates may be the first to go, and you find them here and locate other transmission components here.

Are Driveshafts a Necessary Upgrade with Lift Kits?

Yes. Driveshafts allow the engine to power the transfer case, move torque to the transmission, and send that power through to the rear axle, then out to each tire. These are mounted to the transfer case, front, and rear axle and are responsible for transferring all that power. Unfortunately, they take quite a beating, especially when you're launching your Jeep Wrangler off-road or doing some extreme rock crawling.

If you're installing a lift kit, especially if you have miles on your Wrangler, it would be wise to replace the driveshafts. Their universal joints will have worn, and the lift will put new stress on them while they're at new angles. So, save some trouble and check out some driveshaft options here.

If you think that your driveshafts might be having trouble - or if you've installed a lift kit and want to protect it - make sure you go and get a replacement. They are essential in keeping your Jeep Wrangler drivetrain in working order and can save you thousands of dollars in the long run if they break.

XT Can Keep Your Wrangler Rolling

Jeep Wrangler drivetrain components are known for their durability and long-lasting performance. If you're in the market for replacement parts, we recommend checking out our selection of Jeep Wrangler drivetrain components. From mounts to complete kits, we have what you need.

We carry a wide variety of top-quality products from some of the biggest names in the business, so you can rest assured that your ride will be in good hands. In addition, you can be sure that you're getting the best deal around. Have questions? Contact us today and let us find the perfect Jeep Wrangler drivetrain components for your vehicle.