RAM Commercial ProMaster 2024, Owner'S Manual, Page: 228 / 284

Cooling System Notes
NOTE:
When the vehicle is stopped after a few miles/
kilometers of operation, you may observe vapor coming
from the front of the engine compartment. This is nor-
mally a result of moisture from rain, snow, or high
humidity accumulating on the radiator and being vapor-
ized when the thermostat opens, allowing hot engine
coolant (antifreeze) to enter the radiator.
If an examination of your engine compartment shows
no evidence of radiator or hose leaks, the vehicle may
be safely driven. The vapor will soon dissipate.
•
Do not overfill the coolant expansion bottle.
•
Check the coolant freeze point in the radiator and in
the coolant expansion bottle. If engine coolant
needs to be added, the contents of the coolant
expansion bottle must also be protected against
freezing.
•
If frequent engine coolant additions are required,
the cooling system should be pressure tested for
leaks.
•
Maintain engine coolant concentration at a mini-
mum of 50% OAT coolant (conforming to MS.90032)
and distilled water for proper corrosion protection of
your engine which contains aluminum components.
•
Make sure that the coolant expansion bottle over-
flow hoses are not kinked or obstructed.
•
Keep the front of the radiator clean. If your vehicle is
equipped with air conditioning, keep the front of the
condenser clean.
•
Do not change the thermostat for Summer or Winter
operation. If replacement is ever necessary, install
ONLY the correct type thermostat. Other designs
may result in unsatisfactory engine cooling perfor-
mance, poor gas mileage, and increased emissions.
BRAKE SYSTEM
In order to ensure brake system performance, all brake
system components should be inspected periodically
page 213.
WARNING!
Riding the brakes can lead to brake failure and possi-
bly a collision. Driving with your foot resting or riding
on the brake pedal can result in abnormally high
brake temperatures, excessive lining wear, and pos-
sible brake damage. You would not have your full
braking capacity in an emergency.
Fluid Level Check — Brake Master
Cylinder
The fluid level of the master cylinder should be checked
when performing under the hood service or immedi-
ately if the Brake System Warning Light indicates sys-
tem failure. If necessary, add fluid to bring level within
the designated marks on the side of the reservoir of the
brake master cylinder. Be sure to clean the top of the
master cylinder area before removing cap. With disc
brakes the fluid level can be expected to fall as the
brake linings wear. However, an unexpected drop in
fluid level may be caused by a leak and a system check
should be conducted
page 265.
WARNING!
•
Use only the manufacturer recommended brake
fluid
page 265. Using the wrong type of brake
fluid can severely damage your brake system
and/or impair its performance. The proper type of
brake fluid for your vehicle is also identified on the
original factory installed hydraulic master cylinder
reservoir.
•
To avoid contamination from foreign matter or
moisture, use only new brake fluid or fluid that has
been in a tightly closed container. Keep the master
cylinder reservoir cap secured at all times. Brake
fluid in an open container absorbs moisture from
the air resulting in a lower boiling point. This may
cause it to boil unexpectedly during hard or pro-
longed braking, resulting in sudden brake failure.
This could result in a collision.
•
Overfilling the brake fluid reservoir can result in
spilling brake fluid on hot engine parts, causing
the brake fluid to catch fire. Brake fluid can also
damage painted and vinyl surfaces, care should be
taken to avoid its contact with these surfaces.
•
Do not allow petroleum-based fluid to contaminate
the brake fluid. Brake seal components could be
damaged, causing partial or complete brake fail-
ure. This could result in a collision.
226 SERVICING AND MAINTENANCE