Will, Yes. If your system is still using R-12, Dura-cool has been
successfully just added into the system (at the correct pressure for
Dura-cool ). The lubricants are compatible.
And, No, if your system has been converted to HC-134. The oil for 134
is not compatible with Dura-cool. The system needs to be evacuated, and
leak checked, probably should do a total flushout, and replace the
receiver/ desiccant dryer. Then, vacuum the system to remove all traces of
moisture, and recharge with about 2 1/2 cans of Dura-cool, and the
appropriate oil.
Jim Hupy
Salem, Or