DT12 On-Highway Series Transmission Support (2024)

FAQs

How much transmission fluid does a DT12 hold? ›

Detroit DT12 Specifications

Oil Capacity 10.7–15.4 qts.

The Detroit DT12 Overdrive models, commonly used on Western Star 49X trucks, provide the opportunity for dual PTO usage. An adapter gear is required when using our standard 8-bolt PTOs for the bottom PTO opening. The adapters are currently available for the DT-OV, DT12-OVX, and DT12-OHE Overdrive models.

The countershaft speed sensor should be on the right side. From the parts diagram, it looks to be about in the middle of the transmission case.

As automated manual transmissions (AMT), the DT12-V and DT12-VX combine the benefits of manual and automatic designs. With computer-controlled shifting and clutch engagement, only two pedals are needed to operate the truck: the brake and accelerator.

Delo Syn-AMT XDT SAE 75W-90 is recommended for factory and service fill for Daimler DT-12 automated manual transmissions when operating under severe conditions and in extremely cold or hot environments.

One of the most serious problems a PTO can suffer is a cracked case. This condition can lead to oil loss and eventual transmission failure. Sometimes a gear will chip a tooth because of mishandling or improper shifting.

The power takeoff unit, more commonly known as a PTO, is a mechanical gearbox connected to the transmission that transfers power from the vehicle's engine to an auxiliary component such as a hydraulic pump.

We find that most operators generally run anywhere between 1,100–1,300 RPM, but it can vary.

Common symptoms of a faulty transmission speed sensor include jerky gear changes, malfunctioning cruise control, and an illuminated check engine light. The transmission control module (TCM) knows how fast each shaft should be spinning in each gear.

A bad speed sensor can cause transmission issues and erratic speedometer ratings. A malfunctioning sensor will render the transmission torque converter unable to apply the clutch and form a mechanical link between the engine and transmission. This may also cause your vehicle's cruise control to be disabled.

How do you reset a transmission speed sensor? ›

Turn off your vehicle's ignition and wait patiently for 5 to 10 seconds. Start the engine and allow it to idle for several seconds. Switch off the ignition and wait patiently for another 30 to 40 seconds. Repeat these steps 2 to 3 times in order to reset your vehicle's transmission control module.

The DT12^® On-Highway Series transmissions provide 12 speeds for increased efficiency and flexibility. Its two-pedal design allows the driver to focus on what's ahead instead of what's underfoot, increasing safety and productivity.

An automated manual transmission (AMT) combines a traditional clutch-actuated manual gearbox with a computer-controlled shift actuator and clutch. The best shift patterns are selected electronically to provide optimal power and fuel efficiency.

The DT12 gear ratio has increased from 15 to 19, enabling maximum down speeding to enhance fuel efficiency and low-speed maneuverability. This ratio increase also enables higher GCW ratings.

Oil Capacity: 10-speed: Approx. 26 pints [12 liters].

Vehicles require an average of 4 to 17 US gallons (3.8 to 16 liters) of transmission fluid to fill; the majority of automobiles contain between 12 and 16 quarts (11.3 to 15.1 liters), depending on the car's manufacture and other criteria.

This transmission does not have an oil filter. It is automatic shift, but it is a manual gearbox transmission filled with synthetic gear oil. 75w90 synthetic gear oil is what this transmission takes for oil.