Automatic Transmission Maintenance Guide

The lifespan of a vehicle’s automatic transmission ranges wildly, with some requiring replacement at 100,000 miles, and others lasting for over 300,000. That difference more than doubles the life of a car or truck. 


Most drivers wonder how to make transmission last longer. The best thing to do is stick to a consistent maintenance schedule appropriate for your vehicle. 


In this guide, discover the optimal maintenance and care schedule for your automatic transmission. With our expert checklists at each interval, you can keep your transmission running well for years to come.

What Is An Automatic Transmission?

The transmission is the system in a car or truck that transfers power from the engine to the wheels, through the gearbox. 


An automatic transmission is calibrated to reflexively change to the correct gear in response to changes in driving conditions. In contrast to a stick shift, an automatic transmission doesn’t require the driver to manually shift gears.


Automatic gearboxes make driving easier, reduce accidents and improve fuel efficiency.

How To Keep Your Transmission Healthy

There are several methods drivers can use to keep their automatic transmission systems healthy. Most automatic transmission care falls into three categories:


  • Getting accurate, specific information on your transmission model

  • Using the right transmission fluid 

  • Sticking with an evidence-based care and maintenance schedule

Consider the following best practices in each category.

Consider Your HDV’s Automatic Transmission Type

Different transmission types have different transmission maintenance requirements. You can find your vehicle’s transmission type in its owner’s manual, or by using NHTSA’s VIN lookup service. Automatic transmission types include:


  • Planetary Gear (Torque Converter) Automatic Transmission 

    • This system of “orbiting” gears uses targeted gear ratios to adapt to different conditions, enabling smooth, steady gear shifts.

  • Dual-Clutch Transmission (DCT) 

    • This high-performance transmission system uses two clutches to manipulate gears simultaneously, allowing for lightning-fast gear shifts.

  • Automated Manual Transmission (AMT)

    • This fuel-efficient, low-maintenance transmission requires greater driver engagement, as the driver is meant to manually shift gears with a clutch pedal and lever. 

      • It also incorporates ECUs to automate clutch engagement when necessary. 

How To Choose The Right Transmission Fluid For Your Commercial Vehicle

Every vehicle’s manufacturer specifies the type of transmission fluid compatible with the vehicle. Those specifications outline the parameters of compatible fluids’ chemical compositions and performance. 


To find these specifications, look for the OEM recommendations for your vehicle's make and model number. If you're unsure of your truck’s model or manufacturer, you can find that information using your vehicle's VIN. 


Note that, while all recommended fluids will be compatible, some will enhance performance more than others. Consider severe duty fluid if your work puts high demands on your torque. 

Allison Transmission Fluid Standards

An Allison Transmission requires fluid that meets its TES requirements. When a manufacturer's fluids meet the TES formulas and quality standards, those fluids are compatible with the transmission. Allison Transmission recommends the following fluids for commercial trucks, heavy-duty vehicles, and off-highway use:


  • TES 439: Mineral-based fluid with industry-standard fluid change intervals.

  • TES 353: Synthetic, high-performance fluid with extended drain intervals and enhanced temperature stability and performance. 

For more standard highway driving, TES 668, TES 468, TES 295, and TES 389 are recommended.

Automatic Transmission Care: Maintenance Schedule, Tips & Tricks 

To care for your commercial vehicle’s automatic transmission, follow a regular maintenance schedule. Regularly scheduled care tasks include check-ins, fluid changes, and professional servicing. 


While the optimal maintenance intervals will vary by transmission type, this schedule is a useful guideline and starting point.


Check these aspects every day.


  • Transmission fluid level and color. 

    • With the truck parked and level, run the engine, then pull out the fluid dipstick. Wipe it dry, re-insert it to dip, then pull it out and examine the fluid's color and its level relative to the stick's "full" marker. 

      • If it’s low, find a certified specialist to diagnose the issue. 

    • Compare its color to the chart on the fluid’s container. 

      • If it’s significantly lighter, darker, or muddier, that’s a sign of contamination. 

  • Leaks. 

    • Inspect the undercarriage for drips or puddles. 

    • Note any burning smells, low fluid level, and fluid discoloration.


  • Temperature gauge. 

    • Measure the temperature of your transmission’s fluid with a digital diagnostic scanner or an infrared thermometer. 

      • Make sure the tool is properly calibrated. 

      • If the temperature is over 195 degrees F, or above the overheating level listed in the owner’s manual, take the truck in for inspection.


While engaging in checks, listen for any unusual sounds or vibrations. 

Preventative Care Tips For Your HDV’s Automatic Transmission 

There are several best practices you can engage in to prevent automatic transmission damage. Transmissions can be damaged by freezing fluid, abrupt temperature changes, and undue pressure. To combat these risks, try these tips:


  • Come to a near-complete stop before changing gears.

  • Protect your vehicle's transmission fluid from extreme cold in the winter.

    • Park indoors or in sheltered areas.

    • Use transmission insulation blankets.

    • Utilize engine block heaters.

  • Warm up your truck for 1-2 minutes before driving, even in above-freezing weather.

  • Avoid abrupt acceleration. 

  • Make sure your truck's load isn't over its limit.

It’s also important to replace any spare tire you use quickly. Using one for too long puts excess stress on components. 

Weekly Maintenance (Before Every Trip)

Before every trip, truck and commercial vehicle drivers must conduct systematic maintenance and safety checks to abide by FMCSA regulations. The pre-trip inspection and maintenance checklist includes inspection of key automatic transmission components, including:


  • The transmission’s torque converter or two-element fluid coupling. 

    • Inspect it by running a stall speed test or driving while connected to a scan tool.

  • The condition of the engine, including the gearbox and oil levels. 

    • Inspection should verify the gearbox is securely mounted, functional, and leak-free.

  • Transmission fluid. 

    • Inspection is the same as the daily maintenance check.


As you give your truck a thorough inspection, engage in appropriate maintenance and repair. 


In addition, be sure to rotate your tires every 5000 miles, as tires have a significant effect on the transmission.


Monthly / Quarterly Transmission Servicing (Every 15k - 25k Miles)

Periodically bring your heavy-duty vehicle to be professionally serviced by a certified technician. This is generally a basic service, though it's important to bring any concerns that came up during inspection to your technician for a closer look.


The basic monthly or quarterly service should check your HDV’s transmission fluid level, and refill it or top it off if it’s low. Fix any leaks, and get an oil change if you need one.


Seasonal Transmission Maintenance (Every 30k - 60k Miles)

Two to four times per year, trucks and heavy-duty vehicles require a more thorough automatic transmission service. At these intervals, cleaning and removing debris from the transmission is vital to prevent buildup. Work with a certified technician to:


  • Change your HDV’s transmission fluid 

  • Change filters

  • Inspect and clean component plates and pans

  • Check transmission fluid and hydraulic fluid levels, conditions, and signs of leaks 

  • Perform a transmission flush 

Note that a transmission flush often isn’t necessary at every seasonal servicing. 


An automatic transmission flush uses a high-pressure pump to clear out old fluid, grit, and debris, wholly replacing it with new fluid. This improves lubrication and removes contaminants from the transmission system. 


For some vehicles, a transmission flush every 30k - 60k miles is the best practice. But, for some trucks and HDVs, manufacturers only recommend a flush once every 100,000 miles. 

Annual Certified FMCSA / DOT Inspection 

Once per year, trucks and heavy-duty commercial vehicles must pass an FMCSA / DOT inspection. The details of the inspection are complicated. Our experts can help you navigate the complexities with our Guide to DOT Inspection Checklists.


At Point Spring, we’re ready to help you keep your ride running smoothly all year round. 

Keep Your Automatic Transmission Healthy With Point Spring & Driveshaft Co.

Maintaining a regular care schedule for your truck or car increases the lifespan of its automatic transmission. Moreover, thorough transmission maintenance boosts your ride’s performance across the board. Whether you need a DOT inspection or a seasonal flush, our certified technicians will work with you to get it done.  


To schedule an appointment with Point Spring & Driveshaft Co., contact us by calling 888-787-7746. Or, fill out the form below, and one of our experts will reach out to you.


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