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Maintenance
High-corrosion areas
If you live in an area where your vehicle is 
regularly exposed to corrosive materials, 
corrosion protection is particularly 
important. Some of the common causes 
of accelerated corrosion are road salts, 
dust control chemicals, ocean air and 
industrial pollution.
Moisture breeds corrosion
Moisture creates the conditions in 
which corrosion is most likely to occur. 
For example, corrosion is accelerated 
by high humidity, particularly when 
temperatures are just above freezing. In 
such conditions, the corrosive material is 
kept in contact with the vehicle surfaces 
by moisture that is slow to evaporate.
Mud is particularly corrosive because 
it is slow to dry and holds moisture in 
contact with the vehicle. Although the 
mud appears to be dry, it can still retain 
moisture and promote corrosion.
High temperatures can also accelerate 
corrosion of parts that are not properly 
ventilated so the moisture can be 
dispersed. For all these reasons, it is 
particularly important to keep your 
vehicle clean and free of mud or 
accumulations of other materials. This 
applies not only to the visible surfaces 
but particularly to the underside of the 
vehicle.
To help prevent corrosion
Keep your vehicle clean
The best way to prevent corrosion is 
to keep your vehicle clean and free of 
corrosive materials. Attention to the 
underside of the vehicle is particularly 
important.
•
  If you live in a high-corrosion area — 
where road salts are used, near the 
ocean, areas with industrial pollution, 
acid rain, etc., —, you should take 
extra care to prevent corrosion. In 
winter, hose off the underside of 
your vehicle at least once a month 
and be sure to clean the underside 
thoroughly when winter is over.
•
  When cleaning underneath the 
vehicle, pay particular attention to the 
components under the fenders and 
other areas that are hidden from view. 
Do a thorough job; just dampening 
the accumulated mud rather than 
washing it away will accelerate 
corrosion rather than prevent it. Water 
under high pressure and steam are 
particularly effective in removing 
accumulated mud and corrosive 
materials.
•
  When cleaning lower door panels, 
rocker panels and frame members, be 
sure that drain holes are kept open so 
that moisture can escape and not be 
trapped inside to accelerate corrosion.