Changing Burnt Transmission Fluid: Is It Too Little, Too Late?

Burnt automatic transmission fluid is often a surefire sign that your transmission's best days are well behind it. Conventional wisdom says that once the fluid gets to this state, there's not much you can do to save your transmission outside of an expensive rebuild or replacement. Nevertheless, you might have considered changing the fluid anyway as a last-ditch measure. The big question is whether or not you should give it a shot.

Transmission Fluid Wear and Tear Explained

Transmission fluid has a multitude of uses inside the average automatic transmission. Not only is it tasked with lubricating the various moving parts within the transmission case, it also acts as a coolant and a hydraulic fluid of sorts for the torque converter and various other components.

Transmission fluid contains a variety of detergents, additives and friction modifiers that work in concert to help extend its life cycle. All of these chemical compounds eventually breakdown over time, making the transmission fluid less effective at cooling and lubrication.

What's the Deal with Burnt Fluid?

Burnt transmission fluid is usually the end result of severe neglect or preexisting transmission troubles. In most cases, it's a surefire sign of overheating caused by the fluid's inability to effectively transfer heat away from the transmission and lubricate internal components.

Heat causes the dye used in transmission fluid to change from a cherry-red color when new to a very dark red when it's in need of replacement. Burnt transmission fluid, on the other hand, often looks black and is accompanied by a strong burnt odor.

Don't Make the Switch

So, should you change your burnt transmission fluid? It might be a good idea...and it might not be.

If your transmission fluid has reached the point where it's burnt, then chances are replacing that fluid could simply accelerate your transmission's demise. For instance, the additives and detergents in fresh fluid could easily dislodge deposits and metal shavings, creating new hazards for your transmission that could result in premature failure. 

Keep in mind that there is a small chance that you could get away with changing your transmission fluid. However, that's only if you haven't already experienced the classic symptoms of an ailing tranny (slippage, hard shifting, inability to downshift, loss of overdrive, etc).

What You Should Do Instead

When it comes to the typical automatic transmission, an ounce of prevention is definitely worth a pound of cure. Most experts recommend that you change your transmission fluid at least every 30,000 miles. Some automakers may even recommend waiting until 100,000 miles to change the fluid, depending on the type and brand of fluid used.

If you're dealing with burnt fluid, however, your best bet is to simply invest in a transmission replacement. Depending on the type of vehicle you own and current labor costs, it could be an investment worth thousands of dollars. Preventative maintenance can help you avoid this rather costly scenario. Contact a transmission repair shop, such as Shiftright Transmissions, for further assistance.