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Antifreeze blowing out of expansion tank
in Engine and Transmission
Posted · Edited by darinfreed
I've got a 2002 MR with 400hp E-tec. Antifreeze pushes out of the expansion tank cap. I recently had a hose leak and in the process replaced the thermostat and radiator cap. It had been fine for a while however recently we noticed the antifreeze disappearing. I put a pressure tester on the system and it did not lose any pressure. Upon filling it we noticed the antifreeze pushing out of the cap on the expansion tank. The truck does not over-heat (only when it pushes too much antifreeze out). There is no indication that there is antifreeze in the oil. I noticed the antifreeze in the reservoir looked like it was a little foamy, but I didn't see big air bubbles. After further analysis, it is pushing the cap open and pushing fluid out of the overflow hose.