Hyundai Repair: transaxle or brake fluid?, clutch systems, clutch system

Question
QUESTION: my friend was changing the oil on my 2008 hyundai accent (1.6, 4 cyl) basic model 20,000 miles, manual transmission. he drained about a half qt to a qt before he realized it was not engine oil.  he sealed it back.  the mystery fluid was brown and dirty (sediment). he wasn't sure if it was transaxle fluid or brake fluid and i wouldn't let him add anything without knowing.  in the manual it said to check or add transaxle fluid for a manual transmission to see the hyundai dealer for assistance.  it was the compartment to the right (if you are facing the car's front end) of the engine oil drainage compartment.  what fluid did he drain and can it be fixed without the dealer? and will i mess up the car if i have to drive it, missing the half to a full quart of the fluid?

ANSWER: It's unlikely he drained any brake fluid unless he did so at the clutch release cylinder-- it operates on fluid from the same reservoir as the brake system.  

To find out what he may have drained, find out what size the bolt was he removed.  Draining the transmission requires removal of a 24mm plug, while taking something loose in the clutch system involves a 10mm, 12mm, 14mm, or 17mm wrench.

If the clutch/brake fluid was drained, check the level in the master cylinder.  If it's still present above the minimum line, then you can add without bleeding.  If it's below the minimum line, you may need to bleed the brake and clutch systems.  Use DOT3 or DOT4 brake fluid.  Do not drive the car until the brake system is verified to be operating properly.  Have it towed to a service facility if you cannot do this yourself.

If the transmission fluid was drained, you'll need to fill through the 17mm plug hole in the front of the transmission.  Use 75W-90 gear oil.  It's full when the oil is at the level of the hole.  Driving the car with low transmission gear oil can cause damage to the transmission.  If you cannot do this yourself, you should be okay to drive the car (gently) a couple miles to a service station or shop.





---------- FOLLOW-UP ----------

QUESTION: Where more specifically is the 17 mm plug hole on transmission to add fluid? Thanks again

Answer
It should be on the front of the transmission, about in the center.  The head of the plug faces the driver's side of the car.  I don't recall having to service one of these transmissions yet, so I'm going off a diagram at www.hmaservice.com.  

I cannot attach the diagram here because I don't have permission to use the copyrighted image.  What you can do, however, is register for a free account at www.hmaservice.com, go to the shop manual section for your car, and look at the service procedures there.