2019 Nissan Frontier Transmission & Axle Gear Ratios

Whether you are planning to upgrade your tires, tow a camper, or you simply need to replace a failing differential, understanding the gearing in your 2019 Nissan Frontier is essential. As a midsize truck known for its durability and old-school charm, the 2019 Frontier was offered with a trusty 2.5L inline-four or the workhorse 4.0L V6, paired to three different transmission options and several axle ratios depending on the drivetrain configuration.

Here is the ultimate guide to the 2019 Nissan Frontier transmission and axle gear ratios.

Transmission gear ratios

The 2019 Nissan Frontier came with three transmission options: a 5-speed automatic (available for both engines), a 5-speed manual (exclusive to the 2.5L 4-cylinder), and a 6-speed manual (exclusive to the 4.0L V6). Below are the internal gear ratios for each transmission.

5-Speed Automatic Transmission (RE5R05A)

Available on both the 2.5L I4 and 4.0L V6 models.

5-Speed Manual Transmission (FS5W71C)

Standard on the base S and SV King Cab models equipped with the 2.5L 4-cylinder engine.

6-Speed Manual Transmission (FS6R31A)

Available on 4.0L V6 models, including the PRO-4X trim.

Available axle ratios

Nissan varied the final drive (axle) ratios significantly based on engine size, transmission, and whether the truck was 4x2 or 4x4. The 4-cylinder models utilized much shorter (numerically higher) gears to compensate for the lower power output, while the V6 models used taller gears.

(Note: PRO-4X models feature an electronic locking rear differential (M226 axle), whereas most other trims use the standard C200 rear axle. Axle codes on Nissan often start with the axle type followed by the ratio, e.g., CA31 for C200 3.133 or CC33 for M226 3.357).

How to identify your axle ratio

If you need to replace your rear end or want to re-gear, you need to know what you are currently running. Fortunately, identifying your axle ratio on a 2019 Nissan Frontier is a straightforward process.

• Door-Jamb Sticker: Open the driver's side front door and look for the manufacturer's certification label. Look at the bottom of the sticker for a section labeled "AXLE". You will see a code like CA31 or CC33. The letters denote the axle family (C200 or M226), and the numbers denote the ratio (31 = 3.13, 33 = 3.36, etc.).
• Axle Tag: Crawl underneath the rear of the truck and look at the differential cover. Some models will still have a metal tag bolted to one of the differential cover bolts that explicitly states the ratio or tooth count.
• VIN Decoder: If the sticker is faded or missing, you can run your 17-digit Vehicle Identification Number (VIN) through a Nissan dealership's parts department or a reliable online VIN decoder to pull the original build sheet, which will list the exact factory axle ratio.

Towing vs MPG impact

Your truck's axle ratio is a massive determining factor in how it performs on the highway, off-road, and while towing.

• Numerically lower ratios (e.g., 3.13): These are often referred to as "tall" gears. They allow the engine to run at lower RPMs at highway speeds. This translates to a quieter cabin and notably better fuel economy. However, it requires the engine to work harder to get a heavy load moving, meaning less towing capability and slower off-the-line acceleration.
• Numerically higher ratios (e.g., 3.69, 4.36): These are known as "short" gears. They provide greater torque multiplication to the rear wheels, making them much better for towing, hauling heavy loads, turning larger aftermarket off-road tires, and crawling over rocks. The downside is that your engine will spin at a higher RPM on the interstate, burning more fuel.

Common issues

The driveline in the 2019 Nissan Frontier is largely bulletproof, representing a platform that Nissan had over a decade to perfect. However, as mileage climbs, there are a few things to watch out for:

• Axle Seal Leaks: The C200 and M226 rear axles can occasionally develop leaks at the axle seals. If left unchecked, the differential fluid can contaminate the rear parking brake shoes and cause low fluid levels, leading to internal bearing failure.
• Differential Whine: A persistent whining noise from the rear end during acceleration or deceleration often points to worn ring and pinion gears or failing carrier bearings. This is more common in trucks used for heavy towing or frequent off-roading.
• Electronic Locker Malfunction: On PRO-4X models, the electronic locking differential actuator can sometimes fail or become sluggish due to lack of use or wiring damage from off-roading.

If your Frontier is making a howling sound from the rear end, clunking during gear changes, or leaking gear oil on the driveway, it’s best to have a professional take a look before catastrophic failure occurs.

Find a driveline shop on Repairius.