7 Considerations in Spec’ing a Dump Truck Transmission

There are a lot of details to consider when spec’ing your transmission, but here’s a quick hit of some of the major considerations.

Slow-speed Maneuverability

The challenge for many dump truck applications is they need to get up to highway speeds but also operate around a jobsite with complete control. That means you need a transmission with good slow-speed maneuverability. For example, with Eaton's automated manual transmissions, you could start at the UltraShift PLUS VCS with 10 forward and 3 reverse speeds for fl eets needing basic dump operations, or you can move all the way up to the UltraShift PLUS MXP with 18 forward and 4 reverse speeds. And for super-slow maneuverability, consider the UltraShift PLUS VMS. It has the highest starting gear ratio available.

Reverse Speed Requirements

Most dump applications require extensive operations in reverse. For short distances, 1-2 reverse speeds will probably suit the application, but spec the reverse ratio set that matches your job site requirements.

Off-Road Conditions

Off-road driving can be challenging in mud, soft sand and rutty roads. That's why fl eets should seriously consider an automated manual transmission. It's programmed to maintain constant power to the wheels, plus the driver can take control with manual mode to keep it in a low gear.


Overall, the GCW and material type that you're hauling are going to affect your transmission choice. For example, if you're hauling more than 110,000 lbs., it will probably be best to go with a 13- or 18-speed transmission over a 10-speed so you have better performance.

Auxiliary Transmission

Bolted behind your transmission, an auxiliary transmission is typically used for additional gear reduction for job site work and hauling heavy loads on steep grades, which can be helpful for numerous dump applications.

Maximum Grades

For steep grades, fl eets will want a transmission with a higher amount of forward speeds. An 18-speed has smaller step sizes and overall gear ratio, providing more control in mountainous terrain. Eaton's automated transmissions also have features that help the driver like Hill Start Aid and Skip Shifting. Hill Start Aid prevents unintended rolling for a controlled launch, and Skip Shifting, a load-based feature, allows the transmission to skip gears for smooth acceleration.

PTO Requirements

For most dump applications, you're looking at a power takeoff (PTO) with either a 6-bolt or 8-bolt design, or Eaton also has its optional Thrushaft PTO (on UltraShift PLUS VAS/VCS/ VMS models), providing a more compact, rear-mounted PTO. What's more, Eaton transmissions provide PTO integration so you can transfer a PTO from a manual to automated Eaton transmission and vice versa.