LLYZFED Engine Compartment Battery Distribution Fuse Block 84354721 — OE-fit, reinforced ABS

LLYZFED 84354721 is a direct-fit engine compartment battery distribution fuse block built to replace worn or failed modules on compatible Silverado and Sierra trucks.

Designed as a one-to-one replacement for several OEM numbers, this fuse block consolidates power routing and multiple protective circuits near the battery and firewall. It protects critical engine electrical components and simplifies repairs by matching factory connectors, bolt locations and mounting points so you can restore factory function without custom wiring.

Which Chevy and GMC trucks will this fuse block fit?

This module is manufactured to match OE dimensions and electrical interfaces for late‑model Chevrolet and GMC full‑size trucks. It explicitly fits selected 2017–2019 Silverado and Sierra models, including heavy‑duty variants where noted.

• Chevrolet Silverado 1500 (2017–2019) and 1500 LD (2019)
• Chevrolet Silverado 2500 HD and 3500 HD (2019)
• GMC Sierra 1500 (2017–2019) and 1500 Limited (2019)
• GMC Sierra 2500 HD and 3500 HD (2019)

Which part numbers does it replace, and how confident can I be about fitment?

The LLYZFED 84354721 is engineered to replace several factory part numbers so you can swap it without modifying wiring harnesses. Verify the OEM number on your existing module before ordering to ensure an exact fit.

• Direct replacement for 84354721
• Also compatible with 84043745, 84095551, 84460795
• Uses factory-style connectors and mounting points for straightforward installation

What components and systems does this fuse block protect?

This battery distribution fuse block organizes and safeguards multiple circuits that serve essential engine and safety systems. It helps isolate faults and protect routing for components that influence drivability and cooling.

• Supplies and protects the anti-lock brake pump circuit
• Interfaces with the engine control unit (ECU) power feeds
• Protects circuits feeding the cooling system and related fans

How is installation handled and what materials are used?

The unit is built from reinforced ABS and durable metals to withstand under‑hood conditions. It’s produced to meet or exceed original equipment standards so it installs using the truck’s factory fasteners and plugs directly into the existing harness.

• Reinforced ABS housing with corrosion‑resistant metal contacts
• Heat, abrasion and pressure resistance for long service life
• Direct connector mating and bolt/socket fit for simple replacement

Who is this for? If you own one of the compatible Chevrolet or GMC trucks and you’re experiencing electrical issues tied to under‑hood power distribution, or if you’re proactively replacing a brittle or water‑damaged fuse block, this unit offers an OEM‑style option. It’s suitable for professional mechanics and experienced DIYers who want a direct replacement that restores factory routing, reduces troubleshooting time and avoids custom splicing.