TM 5-3895-383-24 NOTICE Do not use propylene glycol in concentrations that exceed 50  percent  glycol  because  of  propylene  glycol's  reduced heat transfer capability.  Use ethylene glycol in conditions that require additional freeze or anti-boil protection. Coolant Recommendations SMCS Code:  1350; 1352; 1395 The  following  two  coolants  are  used  in  Caterpillar  machine engines: Preferred   -   Caterpillar   Extended   Life   Coolant   (ELC)   or   a commercial  ELC  that  meets  the  Caterpillar  specification  (EC- 1). Acceptable  -  A  Caterpillar  Diesel  Engine  Antifreeze/Coolant (DEAC)   or   a   commercial   heavy-duty   coolant/antifreeze   that meets "ASTM D4985" or "ASTM D5345" specifications. NOTICE Do   not   use   a   commercial   coolant/antifreeze   that   only meets the ASTM D3306 or D4656 specification.  This type of  coolant/antifreeze  is  made  for  light  duty  automotive applications. Caterpillar   recommends   a   1:1   mixture   of   water   and   glycol. This  mixture  of  water  and  glycol  will  provide  optimum  heavy- duty performance as a coolant/antifreeze. NOTE: Caterpillar   DEAC   does   not   require   a   treatment with   an   SCA   at   the   initial   fill.      However,   a commercial    heavy-duty    coolant/antifreeze    that meets "ASTM D4985" or "ASTM D5345" specifications requires a treatment with an SCA at the initial fill. Table 18 Service Life Before Flushing and Before Refilling Coolant Service Life Caterpillar ELC 6000 hours or 6 years Caterpillar DEAC 3000 hours or 3 years Commercial Heavy-Duty Coolant/Antifreeze that 3000 hours or 2 years meets "ASTM D5345" or “TMC RP329" Commercial Heavy-Duty Coolant/Antifreeze that 3000 hours or 1 year meets "ASTM D4985" Extended Life Coolant (ELC) SMCS Code:  1350; 1352; 1395 Caterpillar provides Extended Life Coolant (ELC) for use in the following applications: Heavy-duty diesel engines Natural gas engines Automotive applications The anti-corrosion package for Caterpillar ELC is different from the anti-corrosion package for other coolants.  Caterpillar ELC is an ethylene glycol base coolant.  However, Caterpillar ELC contains organic corrosion inhibitors and antifoam agents with low  amounts  of  nitrite.    Caterpillar  ELC  has  been  formulated with the correct amounts of these additives in order to provide superior   corrosion   protection   for   all   metals   in   the   cooling system of diesel engines. Caterpillar ELC extends the service life of the coolant to 6000 service hours or six years.  ELC does not require the frequent additions   of   a   Supplemental   Coolant   Additive   (SCA).      An Extender is the only additional maintenance that is needed at 3000 service hours or one-half of the service life. ELC is available in a 1:1 premixed cooling solution with distilled water.  The 1:1 premixed cooling solution of ELC will lower the freezing point of the coolant to a temperature of -36°C (-33F). ELC Concentrate can be used to lower the freezing point to - 51C (-60F) for arctic conditions. Containers   of   several   sizes   are   available.      Consult   your Caterpillar dealer for the part numbers. ELC  can  be  recycled.    The  drained  coolant  mixture  can  be distilled in order to remove the ethylene glycol and the water. The ethylene glycol and the water can be reused.  Consul your Caterpillar dealer for more information. Commercial ELC If Caterpillar ELC is not used, then select a commercial ELC that meets the Caterpillar specification of EC-1 and either the "ASTM D5345" specification or the "ASTM D4985" specification.  Do not use a long life coolant that does not meet the EC-1 specification.  Follow the maintenance guide for the coolant from the supplier of the commercial ELC.  Follow the Caterpillar guidelines for the quality of water and the specified coolant change interval. Maintenance Section Cooling System Specifications 1-25