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12V 37A Alternator Carrier Thermo King SB SB-II SB-III SMX RD 45-2254 30-50337-00

12V 37A Alternator Carrier Thermo King SB SB-II SB-III SMX RD 45-2254 30-50337-00

SKU:400-16160

Regular price £400.50 GBP
Regular price £480.60 GBP Sale price £400.50 GBP
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Alternator 12V 37A IR/EF (SKU: 45-2254)

Heavy-Duty Replacement for Carrier & Thermo King Refrigeration

Maintain the critical cooling performance of your transport refrigeration system with this premium 37 Amp alternator. Specifically engineered for the high-vibration environment of diesel-powered refrigeration units, this part provides consistent electrical output to keep your electronics and battery systems powered during long hauls.

RELIABILITY: 100% Brand New components. Built to meet or exceed OEM specifications for stable voltage regulation in harsh transport conditions.

Key Features

  • ✔ IR/EF (Internal Regulator / External Fan)
  • ✔ Direct fit for Carrier & Thermo King units
  • ✔ Heavy-duty bearings for extended service life
  • ✔ High-grade copper windings

Technical Specs

Voltage: 12V
Amperage: 37A
Rotation: CW (Clockwise)
Regulator: Internal (IR)
Fan: External (EF)
B+ Terminal: M6-1.0

Compatibility / Fitment Guide

Brand Application / Models Engine Type
Thermo King SB-190, SB-200, SB-210, SB-300, SB-310, SB-II, SB-III, Sentry, SMX, Super II, MD-II, RD-II Yanmar 3.53L / 4.82L / 4.86L
Carrier Transicold JD, MD, RD Series Units CT4-134, CT4-114 Diesel

OEM Cross Reference

Thermo King: 45-2254, 45-2255, 41-5458, 41-6780, 41-8461, 41-9925, 44-9571
Carrier: 20-44-9571, 29-50340-00, 30-50337-00, 30-50324-00
Leece Neville: 110-399, 110-699, 8MR2130D, 8MR2171F, 8MR2175F, 8MR2181L
Bosch / Lester: 0-120-488-296, 0-120-488-297 / 7478, 7479, 7484, 8616

Questions & Answers

Is this a genuine original part?

This is a premium quality aftermarket replacement part from 4Drive, manufactured to meet or exceed original equipment (OE) standards for fitment and performance.

How do I know if it is compatible?

We recommend checking the SKU/MPN and Cross Reference list provided above. If your original part number matches any of these, it is a guaranteed fit.

What does IR/EF mean for this alternator?

IR stands for Internal Regulator, and EF stands for External Fan. This is the standard configuration for the 37 Amp Leece Neville type alternators used in Thermo King and Carrier trailer units.

Note: Please verify your original part number against the references above before purchasing. All 4Drive products ship from our UK-based logistics center.

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Shipping calculated at checkout. Free shipping over £150. Terms apply