WHAT DOES OLD OR DIRTY TRANSMISSION FLUID DO TO YOUR CAR?

Transmission fluid is a critical component of your vehicle's transmission system, lubricating and cooling to ensure smooth operation and longevity. Over time, however, it can degrade, becoming old or dirty, which can adversely affect your vehicle's performance. The potential problems listed below illustrate the importance of regular transmission fluid changes.

Performance issues

Slipping Gears: Old or dirty transmission fluid loses its ability to properly lubricate the transmission's moving parts. This can lead to gears slipping, where the transmission unexpectedly changes gears or fails to stay in the intended gear, resulting in erratic driving and decreased performance. When this happens, you might notice a delay in acceleration or a sudden change in speed, particularly when shifting from one gear to another.

Hard Shifting: Contaminated transmission fluid can cause increased friction between the transmission's components, making it difficult for the vehicle to shift gears smoothly. This can lead to hard or jerky shifting, which not only makes for unpleasant driving, but can also stress the transmission system. With hard shifting, you may notice a clunk or jolt when the transmission shifts, especially at low speeds or when starting.

Overheating: One of the key roles of transmission fluid is to dissipate heat generated by the transmission. Dirty or old fluid loses its cooling efficiency, leading to overheating. Overheating can cause severe damage to the transmission components, potentially leading to complete transmission failure. If your transmission is overheating, you may smell burning, see warning lights on the dashboard, or experience the transmission entering a "limp mode" to prevent damage.

Longevity concerns

Increased Wear and Tear: As transmission fluid ages, it accumulates contaminants such as metal shavings and debris. These particles can be abrasive, accelerating the wear and tear of transmission components. This increased friction and stress can significantly shorten the lifespan of your transmission. By regularly changing the transmission fluid and filter, you’ll help remove these contaminants and protect the transmission's internal parts.

Corrosion and Damage: Over time, transmission fluid can chemically break down and lose its protective properties. This breakdown can lead to the formation of sludge and varnish on transmission components, causing corrosion and physical damage. Routine maintenance ensures that the fluid remains clean and effective in preventing corrosion and buildup.

Hydraulic Function Compromise: Transmission fluid also functions as a hydraulic fluid, creating the pressure necessary for the transmission to operate properly. Degraded fluid can lead to a loss of hydraulic pressure, resulting in poor performance and potential damage. If you lose hydraulic pressure, you may notice delayed engagement when shifting from park to drive or reverse, indicating a need for fluid replacement.

What you can do to avoid dirty transmission fluid

Scheduled Fluid Changes: Follow your vehicle manufacturer's recommended transmission fluid change intervals, typically every 20,000 km / once per year, or as specified in your owner’s manual. Regular changes ensure the fluid remains clean and effective.

Professional Servicing: Have your transmission fluid checked and replaced by a qualified technician to ensure proper procedures are followed, and any potential issues are identified early.

Routine Checks: Regularly check the transmission fluid level and condition. Healthy transmission fluid should be bright red and have a clean, slightly sweet smell. If the fluid is dark, dirty, or smells burnt, it’s time for a change.

Monitoring Driving: Pay attention to any changes in your vehicle's performance that might indicate transmission fluid issues, such as unusual noises, slipping gears, or hard shifts. Read our General Driving Tips.

Regular maintenance of your transmission fluid is essential to keep your vehicle running smoothly and extend the life of your transmission. It also saves you money by preventing damage that may require expensive repairs. By understanding the impacts of old or dirty transmission fluid on your vehicle's performance and longevity, you can take proactive steps to ensure your transmission remains in top condition. Don’t overlook this critical aspect of vehicle care; schedule regular inspections and fluid changes to protect your investment and enjoy worry-free driving. Book your car in today for a transmission service and flush.