2014 Volvo VNL Transmission & Axle Gear Ratios

The 2014 Volvo VNL is a powerhouse in the heavy-duty commercial trucking industry, renowned for its driver comfort, fuel efficiency, and highly customizable powertrains. Whether you are hauling lightweight dry van freight on flat interstates or pulling heavy flatbed loads through mountainous terrain, the specific combination of your transmission and axle gear ratios plays a massive role in your truck's performance.

Understanding these driveline specifications is critical for fleet owners and owner-operators alike, as it dictates everything from your engine's cruising RPM to your startability on steep grades. Below is a comprehensive breakdown of the transmission and axle gear ratios available for the 2014 Volvo VNL.

Transmission gear ratios

The 2014 Volvo VNL was primarily equipped with Volvo's proprietary I-Shift automated manual transmissions, which revolutionized fuel economy in the heavy-duty market. However, traditional manual transmissions from Eaton Fuller were also widely spec'd by purists and vocational operators.

Volvo I-Shift 12-Speed (Overdrive - ATO2612D)

The overdrive version of the I-Shift is highly popular for highway cruising, allowing the engine to run at lower RPMs at highway speeds.

Volvo I-Shift 12-Speed (Direct Drive - AT2612D)

Direct drive transmissions maximize efficiency by locking 12th gear to a 1:1 ratio, minimizing parasitic power loss through the transmission gear sets.

Eaton Fuller 10-Speed Manual (FRO-16210C)

A staple in the industry for its durability, this 10-speed manual offers a robust alternative for drivers who prefer to shift their own gears.

Available axle ratios

The 2014 Volvo VNL could be built with rear axles from Meritor or Dana Spicer. The rear axle ratio works in tandem with your tire size and transmission top gear to determine your final drive.

Note: The Volvo "XE" (Exceptional Efficiency) package heavily utilized 2.47 and 2.64 ratios paired with a direct-drive transmission to allow downspeeding—cruising at 1,150 RPM at 65 mph.

How to identify your axle ratio

If you are buying a used 2014 Volvo VNL or replacing a damaged differential, it's vital to correctly identify your truck's axle ratio:

• Door-Jamb Decal: Open the driver's door and look for the manufacturer's vehicle identification decal. This sticker lists the truck's GVWR, front/rear axle capacities, and often prints the factory axle ratio right in the powertrain section.
• Axle Tag: Crawl beneath the rear of the truck. Both Meritor and Dana affix a metal tag via two bolts to the differential carrier housing. Wipe away the road grime, and you will find the model number (e.g., MT40-14X) and the specific gear ratio stamped into the metal.
• VIN Decoder / Dealer: You can provide your full 17-character VIN to any authorized Volvo Trucks dealer. Their parts system can pull the exact build sheet, detailing the driveline codes from the factory.

Towing vs MPG impact

In the Class 8 trucking world, "spec'ing" the right ratio is the difference between profitability and running in the red.

• Numerically Lower Ratios (e.g., 2.47, 2.64): Often called "taller" gears. These are heavily favored by fleets running light to standard loads on flat interstates. They drastically lower engine RPMs at cruising speeds, yielding the best possible fuel economy. However, they lack the low-end mechanical leverage for steep climbs or ultra-heavy loads.
• Numerically Higher Ratios (e.g., 3.73, 4.10): Often called "shorter" gears. These are necessary for heavy hauling, logging, or driving through the Rockies. They provide immense low-end torque multiplication, making startability much easier without burning up the clutch, but they force the engine to run at much higher RPMs on the highway, burning significantly more fuel.

Common issues

Heavy-duty drivelines take massive abuse. Over hundreds of thousands of miles, 2014 Volvo VNL owners might encounter a few specific driveline issues:

• Ring & Pinion Whine: As trucks surpass the 500,000-mile mark, gear wear or improper backlash from degraded bearings can result in a distinct whine under load or deceleration.
• Carrier Bearing Wear: The multi-piece driveshafts on longer VNL sleepers require properly functioning carrier bearings. Vibrations at highway speeds are the first symptom of carrier bearing failure.
• Power Divider / Interaxle Differential Failure: If a driver accidentally engages the power divider lock at highway speeds or when a wheel is already spinning, it can catastrophically shear the internal splines.

If you are experiencing vibrations, grinding, or howling from your driveline, do not ignore it until it leaves you stranded. Find a driveline shop on Repairius to get your rig back to peak performance.