Q: My car won't go over 40 mph. What's the problem?

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This morning while the car was in drive it wouldn't move and acted as if it were in neutral, but it would reverse fine. Later in the day it finally cooperated but wouldn't go over 40 mph and the check engine light came on. It won't go into drive now and can't get the codes checked. I looked at the trans fluid and its black, what does black fluid mean &could changing the oil help the issue? Or is it the actual transmission?

My car has 72000 miles.
My car has an automatic transmission.

Hi Elizabeth. Thanks for contacting us tonight. Black transmission fluid is an indication of an overheating problem inside the transmission case. This can be caused by a damaged transmission cooling system, obstruction of debris inside the transmission hydraulic lines or even an inner seal leak. While it’s important to have your transmission fluid flushed as recommended by Hyundai, I’m not 100% certain that this will clear up your issue, but it’s a good place to start. It should be completed as soon as possible as the black fluid is contaminated and needs to be flushed regardless.

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