I just changed my transmission fluid… Why is it still dark?
So you just get home from the auto repair shop, where you had the transmission fluid changed in your vehicle and decide to double check the work and make sure the levels are correct. When you remove your transmission fluid dipstick you can see that the fluid level is right where it is supposed to be, however, you notice something about the fluid condition. The fluid appears to be very dark and you can even notice some debris on the dipstick… I’m sure the first thing that comes through your head is that you just got the run around from an auto shop who took your money and never performed the work. Although this may be the case (although we certainly hope not!), there are a few possible reasons that this could be the case.
So before you jump to conclusions, continue reading to learn more about what could potentially be causing the issue. Also, make sure you refer to the chart above that shows the difference between new and contaminated fluid so you can be certain of your fluids condition.
Things to consider
The first thing to consider is whether or not you had the fluid changed or flushed. When the fluid is changed (commonly referred to as a transmission service or tune up) around 30-40% of the fluid will be changed. This is generally recommended if the fluid is still in good condition but the vehicle has reached the recommended interval for a service. If the service advisor at the auto repair facility recommended a transmission flush and you chose to only have the fluid changed, this is more than likely the reason the fluid is still dark in appearance. If the service advisor recommended to only have the fluid changed and not to flush it, our suggestion would be to take your vehicle back to find out why.
When having the transmission fluid completely flushed, around 80-95% of the fluid will be changed. This is the only way to be sure that all contaminants have been removed from the system. Note: If your transmission was flushed and it still exhibits dirty fluid you should contact your auto repair shop for further diagnosis.
Another thing to consider is that there may be more going on inside the transmission than was expected. This can be especially true on vehicles with no transmission pan where it can more difficult to locate signs of internal issues. Be sure to make the auto repair shop aware of any issues you have experienced with the transmission prior to having the fluid changed. If you noticed firmer shifts, RPM’s going higher than usual, or clunks you may have further issues going on. Remember, these issues may be related to an electrical problem so make sure you bring your vehicle back in to have it thoroughly inspected.
Important Things To Remember…
Before pointing fingers it is important to consider all possibilities that could be contributing to dark fluid. Technicians are human and sometimes, especially when no symptoms of internal problems are present, they can make a mistake in judging the condition of your vehicle’s fluid. It is always better to start with a fluid change when no symptoms are present, rather than starting by removing and replacing the transmission!