aurum

I just bought a used A6 with 50k miles on it. The service history shows that they replaced the overflow tank, cap, and thermostat 3000 miles ago. When I bought the car it was 1.5 liters down below the the max line. So I toped it off. When I checked it the other day it was a little below the min before I opened the cap then the fluid filled up the overflow and spilled out the overflow runoff port at the bottom of the tank. Is it usual to see a drastic overflow level change from venting the overflow tank. Does anyone have an answer for this problem?

Epicman1

Your oil cooler may be leaking...any coolant under car or on belly pan?

kburleysr

Common item. Expensive..$800 to replace.