Manual transmission
Used Eaton Fuller 18-Speed Transmissions
The Eaton Fuller 18-speed is built for heavy-haul and severe work, with a splitter in both ranges. Send us your tag details and we search supplier sources for a used unit that matches.
Eaton Fuller 18-Speed at a glance
- Type
- Manual, twin countershaft, range shift with splitter in low and high range
- Forward speeds
- 18
- Typical applications
- Heavy-haul, oilfield, logging, lowboy and high-GCW tractors
- Example model codes
- RTLO-18918B, RTLO-20918B
Identification tag
How to identify your 18-speed
Check the metal ID tag on the transmission case for the model, serial number and BOM or part number. A model ending in 18, such as RTLO-18918B, indicates an 18-speed.
If the tag is gone, the VIN and build sheet are the next best source. A photo of the shift knob and case also helps us confirm the family.
01How an 18-speed shifts
The splitter works in both low and high range, so each gear can be split into two steps. That gives the driver tight ratio steps for starting and pulling very heavy loads.
02Torque rating and ratios
18-speeds are built in different torque capacities. Match the model and BOM to your engine's torque rating so the transmission is not undersized for the application.
03Input shaft, clutch, air system and PTO
Confirm input shaft spline size and length against your clutch, and check the air-shift knob and fittings. Heavy-haul trucks often run PTOs, so note the opening and PTO model.
04Core and exchange
Core charges or exchange terms may apply depending on the supplier. If they do, they are confirmed on your quote before you commit, along with availability and freight.
Configuration
What we'll ask to match your unit
- What model, serial number and BOM are on the ID tag?
- What engine and torque rating is it behind?
- What is the truck year, make, model and VIN?
- What work does the truck do (heavy-haul, oilfield, logging)?
- Does the truck use a PTO, and which opening?
- Do you need the clutch, shift knob or shift tower too?
FAQ
Eaton Fuller 18-Speed questions
Why choose an 18-speed over a 13-speed?
The 18-speed splits in both ranges, so it gives more ratio steps at low speed. That helps when starting and climbing with very heavy loads.
Does torque rating matter on a used 18-speed?
Yes. The transmission should be rated for at least your engine's torque output. The model number and BOM tell us the rating to search for.
Can I install an 18-speed in place of a 10-speed?
It is a bigger job than a straight replacement. Shifter, air lines and sometimes crossmembers or driveline length change. Talk to your shop first.
Do you test the transmissions you source?
We are a sourcing company and do not run our own testing. Any condition information a supplier provides is shared on your quote.
How do I start?
Call or submit the form with your tag details and VIN. We search supplier sources nationwide and confirm availability and freight on your quote.
Ready when you are
Need a Eaton Fuller 18-Speed? Send the tag number.
Have your engine serial number or transmission tag and VIN handy. If you don't, we'll help you find them.
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