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Heavy-Duty Alternators That Handle the Heat

New Indo Technical Team · 2026-05-13
Delco Remy heavy-duty brushless alternator Heavy-duty alternator in mining application

Some applications demand very high current in harsh environments. Fire trucks and off-highway equipment operate under-hood in high ambient temperatures and have large electrical loads. Delco Remy’s 55SI and 40SI heavy-duty brushless alternators are designed for these conditions.

Features of 55SI and 40SI High-Output Alternators

  • Brushless design and Remote Sense functionality allow them to survive extreme under-hood temperatures while maintaining high output
  • High output at engine idle ensures that emergency lighting, pumps and other critical loads have sufficient power even when the engine is idling
  • Hairpin stator and robust frame design provide exceptional durability — only a handful of 55SI units have been returned in over 15 years of service
  • These models were originally developed for off-highway equipment manufacturers and have a proven track record for reliability
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