Fuller Transmission Upgrade-RTLO18918B

Eaton Fuller Transmission

Your truck requires a transmission that is reliable, versatile, efficient, and safe. The Eaton-Fuller RTLO18918B speed transmission is built for the job. This model of fuller is strong, adaptable, and easy to use.  It is the right gear to keep the engine running at the correct RPM, save fuel, help increase semi-truck engine longevity.  Most of all, it will help deliver the torque needed to get those heavy loads moving. No matter where your journey takes you, there’s a gear for every situation a local truck driver or an over the road truck driver might encounter.

Fuller Transmission RTLO18918B Facts & Features

The RTLO18918B Eaton Fuller Transmission features unbeatable versatility.  The transmission operates as a 9, 10, 13, or 18-speed transmission, with 19.7 to 1 overall reduction and 14.40 low gear.  It also has economical performance with 0.73 and 0.86 overdrives for efficient cruise RPMs. Truckers have smoother shifting thanks to patented low-inertia technology.  During upshifts, both the lever and splitter buttons move together.  The low-inertia main shaft quickly goes to synchronous and the results are fast and easy shifts.


Exclusive output seal design improves seal life and eliminates the potential for seal damage during yoke removal. Thanks to design improvements, the RTLO18918B 13 and 18-speed transmission also feature faster, smoother range and splitter shifts. On select models, an optimized lubrication system provides increased cooling and lubrication for more difficult or harder-working applications.


Other features include:

  • Unequaled ratio versatility due to close, even steps in both HI and LO range
  • Enhanced reverse operation safety due to multiple slow reverse ratios
  • Quieter operation and increased durability due to helical gears in auxiliary section

How The RTLO18918B Works

The Eaton-Fuller 18 speed transmission has a ‘H’ pattern. The driver uses second, third, fourth, and fifth, then splits up into high range; then, the H pattern shifts again for sixth, seventh, eighth, and ninth gear. After reaching the ninth gear, split up to overdrive for the top gear. There are plenty of other gears in between, as all main gears have a high range and a low range so that the driver can split any of the gears, twice more.


It might sound a bit complicated at first, but it really isn’t. A truck driver may find that the gear being used, may not be quite the right one for where he wants the RPM’s to be. In this case, you can simply split up or down accordingly, matching the RPM’s to the engine’s sweet spot. Heavy Truck Drivers who like floating gears (which is never recommended) should love the 18 speed— 12 of the 18 gears available do not require moving the shifter, as they have split gears with a flick of the finger or thumb.


Concerned about the conversion and what else you might need? Typically, you’re looking at 5 things with fuller transmissions, depending on what you are replacing:

  • Shortening your driveline (around 3 inches)
  • Bellhousing, as this is a forced lubed system and needs to accommodate the Halo system, Yoke, Knob, & Shift tower

Purchase Your RTLO18918B 18 Speed Transmission


LKQ Heavy Truck can replace your tired, underperforming 10-speed transmission with an Eaton-Fuller RTLO18918B 18 speed transmission, with NO UPCHARGE for the core.

LKQ Heavy Truck can frequently buy heavy truck transmissions in bulk and at deep discounts. In turn, we pass those savings onto our customers. If you need a back-up or simply spend too much time in the driver seat unable to find the right gear, check out the RTLO18918B Fuller Transmission.  Available shipping from several locations throughout the US, typically 2-3 business days.


Contact us today to learn more about our fuller transmission offers or call us at 877-557-8782.

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