My ATF cooler failed a couple of weeks ago, leaving coolant in my ATF and
ATF in my coolant. (This despite replacing the cooler a year-and-a-half ago
to prevent just such a failure -- aarrggh.)

A new cooler has been installed and all of the affected fluids have been
flushed and replaced, and in particular the coolant's been drained twice
and replaced. Yet I can still see a brown film in the coolant expansion
tank, and I'm still having trouble with the coolant level warning light
going off. My mechanic's current theory is that the ATF residue changes the
viscosity of the coolant sufficiently to cause the sensor to trip.

Is there something more we can be doing to get the ATF residue out of the
coolant? Is there any way to really clean out the cooling system?

Mark Pry
1990 GL