Chemical Cleaning
WARNING: This page is about a different car, the 2016 Jeep Wrangler and 2015 Jeep Wrangler. However, it is still accessible from the selected car via links, so may be relevant.
If visual inspection indicates the formation of sludge or scaly deposits, use a radiator cleaner, Mopar® Radiator Kleen or equivalent, before flushing. This will soften scale and other deposits and aid the flushing operation.
CAUTION:
Be sure instructions on the container are followed.