Allison Transmission Speed Sensor Location: Expert Tips and Guide

Allison Transmission has been a leader in the automotive industry, particularly in the realm of heavy-duty vehicles. Known for their durability and efficiency, Allison Transmissions are the go-to choice for many. But like any complex machinery, they have multiple components that need to function in harmony, one of which is the speed sensor.

Locating the Allison Transmission Speed Sensor is crucial for the optimal performance of your vehicle. The sensor is generally located on the transmission case and can be accessed by removing certain components. A faulty sensor can lead to erratic shifting and poor fuel efficiency.

Allison transmission speedometer dropping out, output shaft speed sensor codes, tranny stumbling

Locating the Allison Transmission Speed Sensor

allison transmission speed sensor location

Park Your Vehicle: 

Ensure your vehicle is parked on a level surface and the engine is turned off.

Safety First: 

Put on safety gear, including gloves and safety goggles.

Access the Transmission: 

Open the hood and locate the transmission. In most cases, the speed sensor is located on the transmission case.

Identify the Sensor: 

Look for a small component with electrical wires coming out of it. This is usually the speed sensor.

Consult the Manual: 

If you’re having difficulty, consult your vehicle’s manual for the exact location of the speed sensor.

Visual Confirmation: 

Once located, visually inspect the sensor for any signs of wear or damage.

Tools Required

Socket SetFor removing bolts
ScrewdriverFor prying and unscrewing
Safety GlovesHand protection
Safety GogglesEye protection
Vehicle ManualFor reference

Transmission Speed Sensor Common Problems and Solutions

Common Problems

Here are some issues you might encounter with a faulty Allison Transmission Speed Sensor:

  • Erratic Shifting: Unexpected gear changes while driving.
  • Poor Fuel Efficiency: The vehicle consumes more fuel than usual.
  • Transmission Slippage: The transmission unexpectedly changes out of gear while driving.
  • Warning Lights: Transmission or check engine light comes on.

Troubleshooting Tips

  1. Check for Loose Connections: Ensure the electrical connections to the sensor are secure.
  2. Clean the Sensor: Sometimes, dirt and grime can interfere with the sensor’s function.
  3. Use a Diagnostic Tool: A specialized diagnostic tool can provide more information on the issue.
  4. Consult the Manual: Your vehicle’s manual may have specific troubleshooting steps.
  5. Professional Help: If all else fails, it might be time to consult a professional.

Product Recommendation

For those who prefer a DIY approach, we recommend using a specialized transmission diagnostic tool. Here’s a reliable option from Amazon: XYZ Diagnostic Tool.

The Anatomy of Allison Transmission

The Building Blocks of Allison Transmission

Allison Transmissions are complex pieces of machinery, designed to handle heavy-duty tasks with ease. They consist of several key components, each with a specific function:

  • Torque Converter: This replaces the clutch in manual transmissions, allowing the vehicle to stop without stalling the engine.
  • Planetary Gear Sets: These are the heart of the transmission, responsible for providing different gear ratios.
  • Clutches and Bands: These components work to engage and disengage planetary gears.
  • Valve Body: This is the transmission’s control center, directing hydraulic fluid to the clutches and bands to engage gears.
  • Output Shaft: This takes the torque from the transmission to the vehicle’s wheels.

The Role of the Speed Sensor

The speed sensor is a small but crucial component. It’s generally located on the transmission case and is responsible for monitoring the rotational speed of the gears. This data is sent to the vehicle’s computer, which then makes real-time adjustments to optimize performance. In essence, the speed sensor is the eyes of the transmission, constantly feeding it information.

Why Speed Sensors Matter

The Function of Speed Sensors

Speed sensors in Allison Transmissions serve multiple purposes:

  • Gear Shifting: The sensor helps the transmission decide when to shift gears by providing data on the rotational speed of the gears.
  • Fuel Efficiency: By optimizing gear shifts, the sensor indirectly contributes to better fuel efficiency.
  • Safety: Accurate speed data ensures that the vehicle operates within safe parameters, reducing the risk of transmission-related accidents.

Real-World Implications

Imagine driving on a highway and your vehicle suddenly shifts to a lower gear without warning. Not only is this jarring, but it’s also dangerous. A faulty speed sensor can lead to such erratic behavior. On the flip side, a fully functional sensor ensures smooth gear shifts, optimal fuel consumption, and overall safer driving.

You Can See:Allison Transmission Output Speed Sensor Location.

Allison Transmission Output Speed Sensor Testing

If you have an Allison Transmission and are having problems with the output speed sensor, there are some things you can do to test it. First, check the transmission fluid level and condition. If it is low or dirty, it could be causing the problem.

Next, check for any loose wires or connections. If everything looks good there, then it’s time to test the sensor itself. There are a few ways to do this, but the most common is with a multimeter.

You’ll want to connect the positive lead to one of the terminals on the sensor and ground the negative lead on the other terminal. With the engine off, you should see a reading of around 1-2 ohms. If you see a reading of 0 ohms or infinity (open circuit), then the sensor is bad and needs to be replaced.

If your multimeter doesn’t have a direct ohm setting, you can also use the continuity setting. This will give you a beeping sound if there is a connection between the two terminals. Again, with the engine off, you should hear a continuous beep if the sensor is good.

If not, then it’s time for a new one!

Allison Transmission Speed Sensor Location



What are the symptoms of a faulty Allison Transmission Speed Sensor?

Erratic shifting, poor fuel efficiency, and warning lights on the dashboard are common symptoms.

How do I test the Allison Transmission Speed Sensor?

You can use a specialized diagnostic tool to read the sensor’s data. Alternatively, a multimeter can be used to measure the sensor’s ohms.

What is the Allison 1000 Speed Sensor Location?

The Allison 1000 speed sensor is generally located on the transmission case, often near the rear of the unit.

How do I resolve Allison Transmission Speed Sensor Problems?

Start by checking for loose connections, cleaning the sensor, and using a diagnostic tool. If the problem persists, consult a professional.

How do I measure Allison Transmission Speed Sensor Ohms?

A multimeter can be used to measure the sensor’s resistance. The specific ohm range can usually be found in your vehicle’s manual.

What tools do I need to locate the speed sensor?

Basic tools like a socket set, screwdriver, safety gloves, and goggles are generally sufficient.


We’ve taken you through the intricacies of the Allison Transmission, focusing on the pivotal role of the speed sensor. From its anatomy to its significance, from locating it to troubleshooting common issues, we’ve covered it all. The speed sensor is not just a piece of hardware; it’s a critical component that ensures your vehicle runs smoothly and safely.

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  • Alex Gearhart

    Alex Gearhart, an automotive expert specializing in transmissions, has over a decade of hands-on industry experience. With extensive knowledge in manual and automatic systems, Alex is passionate about educating car enthusiasts on vehicle maintenance. As the chief author at, Alex simplifies complex concepts for readers, helping them make informed decisions about their vehicles. Outside of work, Alex enjoys road trips, restoring classic cars, and exploring new automotive technologies.

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