DB Electrical Alternator for Thermo King — 12V 37A CW Direct-Fit with Internal Regulator

The DB Electrical 400-24100 is a 12V, 37A clockwise-rotation alternator designed as a direct-fit replacement for specific Thermo King refrigeration unit models and multiple OEM part numbers.

If you operate Thermo King transport refrigeration systems or maintain fleets that use the listed SB, SL, SMX and Super series units, this alternator supplies a like-for-like charging solution built to match common OEM specifications. The unit is engineered for straightforward installation, follows common pin and mounting arrangements, and replaces several manufacturer references so you can restore reliable charging with minimal downtime. Verify your existing part number and fitment before ordering to ensure compatibility.

Which Thermo King models does this alternator work with?

This alternator is compatible with many Thermo King refrigeration models used on trucks and trailers. It fits a wide range of SB, SL, SMX and Super series units as well as dedicated LND and Sentry variants. Check that your model and serial information match the list to confirm interchangeability.

• Compatible models: LND 50, SB-190/200/210/300/310, SB-II/III (+ MAX/SR variants)
• Also fits: SDZ, Sentry, SL100/200/300/400 (including -e and SR2 versions)
• Works with: SMX, SMX II, SMX SR, Super II, Super II SR, Super II TC

What electrical and mechanical specs should I expect?

The alternator delivers 12 volts at 37 amps with a clockwise rotation. It includes an internal regulator (IR) and is designed to meet the electrical output needs of the listed refrigeration units. The mechanical layout is a direct-fit style intended to match OEM mounting points and electrical connectors.

• Voltage: 12 V, Amperage: 37 A
• Rotation: Clockwise (CW)
• Regulator: Internal (IR) for simplified wiring
• Direct-fit design to reduce installation time

Which OEM part numbers does it replace?

This DB Electrical alternator is manufactured to substitute numerous OEM and aftermarket references, making it easier to source a compatible replacement across different parts catalogs. Use the cross-reference list to match your existing number before purchasing.

• Arrowhead: 400-24100 and older IA1488 references
• Bosch: 0-120-488-296 and 9-120-006-023 / 9-120-060-023
• Carrier Transicold, Delco Reman, Mahle, Letrika/Iskra and other listed equivalents
• Additional references: CARGO 111672, LESTER 12224, REMY 50955

How straightforward is the installation and what should I prepare?

Designed as a direct-fit replacement, the alternator typically installs using the existing mounting brackets and electrical connectors found on the applicable Thermo King units. Basic hand tools and standard electrical safety precautions are all that’s usually required. Always disconnect battery power and confirm polarity and connector alignment before finalizing installation.

• No vehicle modification required for listed applications
• Keep tools for pulley tension and bracket bolts handy
• Disconnect batteries and confirm connector orientation
• Test charging output after installation to verify operation

Who this is for: Technicians, fleet maintenance managers, refrigeration service shops and DIY professionals who need a reliable, direct-fit alternator replacement for Thermo King refrigeration units. If you require a 12V, 37A alternator that cross-references common OEM numbers and supports clockwise rotation installations, the DB Electrical 400-24100 is engineered for those applications. Remember to confirm the existing part number and model fitment before purchase to ensure compatibility.