How to Manually Shift Allison Transmission

To manually shift an Allison transmission, first turn off the engine and apply the handbrake. Move the gear selector to neutral and place your foot on the brake pedal. Turn on the ignition, but do not start the engine yet.

Move the gear selector into drive while pressing down lightly on both pedals at once—the brake and accelerator—and then release them both together as well. You should feel a slight jerk as you move through each gear. When shifting gears, always make sure to keep your foot light on both pedals until you have shifted completely into a different gear.

Repeat this process for all of your desired gears until you reach the highest one available in your particular model of transmission.

  • Bring the engine to a stop and apply the parking brake
  • Move the transmission shift lever into neutral (N)
  • Depress and hold down the clutch pedal with your foot while pushing in on the range selector knob located on top of shifter handle
  • This will allow you to move the shifter through each gear without engaging it
  • Continue to depress and hold down onthe clutch pedal until Step 4 is complete
  • With your other hand, use the thumb button next to the shift lever handle to move it up or down between gears as needed, such as from N-D-R-M etc
  • ,without letting go of either buttons or shifting out of neutral position during this step
  • Make sure not to press too hard when moving between gears so that it does not slip into any other gear accidentally while performing this maneuver
  • When you reach desired gear setting release both buttons at same time then slowly let off on clutch pedal till normal idle speed is achieved for vehicle operation in selected gear

Allison Transmission Operation

Can You Manually Shift an Automatic Transmission?

The short answer is no, you can’t manually shift an automatic transmission. Automatic transmissions are designed to automatically change gears as the vehicle moves and its engine speed increases or decreases. This helps ensure that the engine is always operating at its peak efficiency and performance level for a given situation.

Manual transmissions, on the other hand, require the driver to move a gear selector lever and use a clutch pedal in order to shift gears manually. While it may seem like an easy solution in theory, attempting to manually shift an automatic transmission would likely cause major damage due to improper control of fuel delivery, hydraulic pressure, and shifting timing which could ultimately result in costly repairs or even total failure of the transmission system. In addition, manual shifts do not provide any advantages compared with automatic transmissions when it comes to fuel economy or acceleration; in fact they often hurt both metrics since most drivers lack experience with manual shifting techniques needed for optimal performance.

For these reasons it’s best just leave your automatic transmission alone!

How Do You Manually Shift an Automatic Truck?

Manually shifting an automatic truck may seem intimidating at first, but it’s actually quite simple. The process involves pressing down on the gear selector lever and moving it to the left or right until you reach your desired gear. You’ll feel a slight click when the gear is engaged, so be sure to pay attention for this indicator.

For those who are unfamiliar with manual transmissions, some trucks come equipped with shift-override buttons that allow you to select gears without having to use the shifter itself. These override buttons are usually located near the driver’s seat or on the center console of your vehicle. To ensure smooth operation of your vehicle while manually shifting, make sure all service lights are off and no other functions—such as cruise control—are operating before engaging in manual mode.

Another important factor is making sure all occupants in your truck have their seatbelts fastened; failure to do so could result in injury during sudden changes in speed or direction that can occur when navigating terrain or obstacles with a manual transmission vehicle.

What is the Mode Button for on an Allison Transmission?

The mode button on an Allison Transmission is designed to give drivers ultimate control over their vehicle’s shift points. It allows them to choose between two different modes—Performance Mode and Economy Mode—which can significantly affect the engine performance, fuel economy, and overall driving experience. In Performance Mode, the transmission will shift earlier and more aggressively in order to provide maximum power for acceleration and hill climbing.

On the other hand, when switched into Economy Mode, the transmission will shift later in order to preserve fuel efficiency. The precise shifting of the mode button also gives drivers greater ability to customize their driving depending on current road conditions or individual preferences. Ultimately, this feature helps make sure that your driving experience feels exactly how you want it–whether it be a smooth ride with maximum power or one which emphasizes efficiency above all else.

What Would Cause an Allison Transmission to Not Shift in Gear?

An Allison transmission not shifting into gear can have several causes, ranging from something as simple as low fluid levels to a major mechanical issue. The most common cause of an Allison transmission not shifting is the solenoid or pressure control valve sticking in the closed position, preventing fluid from entering and activating the shift valves. This can be caused by dirty or contaminated fluid, faulty wiring or connectors, worn or damaged components within the valve body, and even excessive heat build-up inside of the transmission itself due to heavy loads or frequent stop-and-go driving conditions.

Other potential causes include worn out clutch plates that are unable to provide enough friction for shifts to occur properly; broken shifter forks; air bubbles trapped in hydraulic lines; malfunctioning electronic sensors that send incorrect signals back to the TCM (transmission control module); foreign objects stuck between gears and blocking movement; insufficient lubrication on internal parts causing them to seize up when attempting a shift; and lastly improper adjustment of bands/linkages resulting in no engagement at all. It’s important for any vehicle owner experiencing these issues to take their car into an experienced automotive professional for diagnosis and repair before further damage occurs.

How to Manually Shift Allison Transmission


How to Manually Shift an Automatic Transmission

Shifting an automatic transmission manually can be a great way to improve your driving experience. To do this, you must first locate the manual shift mode on the gear selector, typically marked with letters such as “M” or “S”. Once engaged, use the up and down arrows or paddles on either side of the steering wheel to move through each gear.

It is important to remember that when shifting manually, it is best not to rev too high and always allow time for proper acceleration between gears.

Why Do I Have to Manually Shift My Automatic Transmission

Most modern vehicles with automatic transmissions use a transmission control unit (TCU) to regulate the shifts, allowing the driver to select between gears without having to manually shift. However, some cars feature a manual mode for their automatic transmissions that allows for greater control over shifting and improved performance in certain driving conditions. By engaging this mode, drivers can override the TCU’s automated shifting decisions and choose when they want their vehicle to shift into higher or lower gears.

This manual shifting capability is especially useful on hilly terrain where more precise gear selection can help ensure optimum acceleration and fuel efficiency.

How to Use Plus And Minus on Gear Shift

Using the plus and minus on a gear shift is simple; all you need to do is press the plus button for an upshift and the minus button for a downshift. When pushing either of these buttons, your vehicle will automatically shift into higher or lower gears accordingly. It’s important to remember that when using this feature, it should only be done while traveling at slower speeds as any sudden changes in acceleration can be dangerous.


Manually shifting an Allison transmission requires the driver to understand how to properly use clutch and gear combinations to switch gears. It is important for drivers who choose this method of shifting to take their time, practice often, and be patient with themselves so that they can become comfortable using this form of gear-shifting. With proper use and practice, any driver can master manual shifting in an Allison transmission vehicle.


  • 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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