I wish I could remember what I used. It came in a white qrt size container with a handle. Got it from advance and autozone. It was good stuff. Sorry I can't be more help <img src="/forums/images/graemlins/confused.gif" alt="" />

I think a cleaner and repeated flushes over time will fix it eventually. Does the heater core make the sound with the cabin temp control on cold? Doesn't that stop the coolant flow through the heater core?

'97 Montero 'LSR' - 4.6 gears & factory rear locker, 33" Procomp muds on 15x8 steelies, 50mm coil spacers, T-bar crank, Airlift, sans rear sway, 50mm rear frame & fuel tank lift, Aisins, ARB front bumper + 10k lb winch, 50mm DIY body lift, rock sliders, cut rear quarter panels...