Q: Lost all transmission fluid near radiator overnight 2004 GMC Sierra

asked by on March 07, 2017

What would cause all of my transmission fluid to leak out near coolant lines over night

My car has 166000 miles.
My car has an automatic transmission.

Hello - there are fittings at the radiator where the transmission oil lines go into the radiator side tank. Perhaps one or both of these fittings came loose, or broke - leaking fluid from that point? Gravity would do the rest. I recommend an oil leak inspection performed by a mobile, professional mechanic, such as one from YourMechanic, who will come to your location, diagnose this problem, and give you an accurate assessment of damage and cost estimate for repairs.

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