Dear Metallo,

Hope you're well and stay so! Based on two decades of reading BB posts, the symptoms you report are consistent with a failed head-gasket. Your mechanic should be able to check for the presence of exhaust gases in the coolant.

You can do another test. Pull the oil dipstick. If the oil looks milky - like a pale chocolate milk - that's a sign of coolant in the oil. Such mixing occurs, when the headgasket fails. If the oil looks "normal" - golden or black - that suggests there is no mixing of coolant and oil.

Absent head-gasket failure, the two systems - cooling and lubrication - cannot connect, unless your oil cooler has, somehow, failed internally.

Hope this helps.

Yours faithfully,

Spook