View all Posts

FEB 19, 2026

How to Choose the Right Power Configuration for Your HLF Tuck Under Liftgate

Selecting the correct power configuration for your Waltco HLF Tuck Under lift gate is crucial for ensuring proper functionality, safe operation, and long-term reliability.

• Documentation Resources from Thieman
• Overview: Why Power Configuration Matters
• Factory and Field Power Kits: What’s Available for HLF
• Pre-Mounted Power Units: Unique to HLF
• Circuit Breakers and Fuse Protection
• Trailer and Tractor Wiring Options
• Power Down vs. Gravity Down Liftgate Styles: What to Choose
• Safety and Control Enhancements
• Summary: Which Configuration is Right for You?

Documentation Resources from Thieman

Information in this article is sourced from Waltco HLF manuals and technical guides, as well as LiftGateMe’s technical review of those documents. Always refer to your specific liftgate’s manuals for complete procedures and serial number, model, and year-specific details.

Reference PDFs used:

• Waltco HLF Parts Manual
• Waltco HLF Installation Manual

Overview: Why Power Configuration Matters

The Waltco HLF tuck-under supports a wide range of power and electrical configurations tailored to both truck and trailer applications. Because HLF liftgates often see higher duty cycles, heavier capacities (up to 5,000 lbs), and more complex routing needs, choosing the right electrical setup is essential.

Compared to EM and C-Series models, HLF power setups:

• Include more factory-supported kits
• Have greater compatibility with trailer wiring systems
• Provide advanced safety options like cab shut-off switches and cycle counters

Factory and Field Power Kits: What’s Available for HLF

The HLF Series offers a variety of supported wiring and power kits directly from Waltco:

These kits are shown in the Installation Manual, pages 36–49【13†WS】.

EM / C-Series Comparison:

• EM and C-Series do not include certified trailer kits.
• Auxiliary battery kits and shut-off switches are not standard or emphasized for EM/C.
• HLF includes pre-wired harness options; EM/C often require more field wiring.

Pre-Mounted Power Units: Unique to HLF

Waltco notes that for the HLF lift gate, the power unit is often pre-mounted and fully tested at the factory before shipping. This includes the pump, hydraulic hoses, electrical solenoids, and sometimes even a pre-installed cab shut-off or cycle counter harness【13†WS, pg. 10–13】【12†PM, pg. 14–15】.

This is a key difference from the EM and C-Series, where power units are generally field-mounted, requiring additional wiring, adjustment, and setup during install.

Benefit:

Pre-mounted configurations reduce install time and wiring mistakes, especially for high-volume or fleet-based deployments.

Circuit Breakers and Fuse Protection

The HLF requires circuit breakers rated by model:

• 150A for HLF-25, HLF-30, HLF-40
• 200A for HLF-50

This protection is included in Waltco’s official schematics (PM-796) and should be mounted directly to the vehicle battery using a copper terminal link【13†WS, pg. 21】【12†PM, pg. 15】.

Cycle counter, shut-off switch, and dual control options also require appropriate fuse protection (15A fuses in inline holders).

EM / C-Series Comparison:

• Similar fuse types (15A) are used
• Circuit breaker capacity typically does not exceed 150A for EM/C models

Trailer and Tractor Wiring Options

The HLF Series is designed for trailer compatibility. Two kits are available:

• Trailer Interface Kit (#80000878)
• Canadian Certified Trailer Interface (#80001388)

These support:

• Dual pole sockets
• Battery-to-trailer charging logic
• Pre-installed ground and power separation

The Trailer Kit installation includes:

• Dual pole socket mounted on trailer nose
• 0 GA cables (0-guage cable)
• Dielectric grease and sealed connections
• Ground cable from socket to trailer frame

Source: WS Manual, pg. 43–49【13†WS】

EM / C Liftgate Model Wiring Comparison:

• No official support for trailer-mounted wiring
• Typically used on box trucks with single battery feed

Power Down vs. Gravity Down Liftgate Styles: What to Choose

Waltco HLF tuck under lift gate models come standard with gravity down, but a power down option is available.

• Gravity down uses valve-controlled fluid return
• Power down provides faster lowering and better control under heavy load or incline

You can add:

• Power down pump upgrade
• Additional solenoids and wiring (must follow schematic PM-796)

Hydraulic layout provided in PM-795/796【12†PM, pg. 14–15】【13†WS, pg. 22】.

EM / C Models Power and Gravity Down Comparison:

• Also support gravity or power down
• Power down less emphasized in manuals and not pre-wired
• HLF has more solenoid and valve placement detail

Safety and Control Enhancements

For larger fleets or safety-conscious operations, the following HLF options improve driver and load safety:

Cab Shut-Off Switch (Kit #80000827)

• Mounted in driver cab
• Disables liftgate when not in use
• Adds protection from unauthorized use

Cycle Counter (Kit #80001312)

• Logs number of liftgate operations
• Helps schedule preventive maintenance every 3,000 cycles

Dual Controls (Kit #80000437)

• Adds switch box to second vehicle location
• Allows operator to control gate from rear or side

All kits are shown with wiring schematics in the Installation Manual【13†WS, pg. 36–45】.

EM / C-Series Comparison:

• Dual control offered but not as fully integrated

Summary: Which Configuration is Right for You?

For each setup, always follow Waltco’s PM-796 schematic and ensure fuse sizing matches gate model.

Final Notes

The Waltco HLF tuck-under model supports more power and safety configurations than either the EM or C-Series. Whether you're installing on a heavy-duty box truck or configuring a certified trailer buildout, HLF kits are designed to make wiring and usage secure, fast, and reliable.

Always use authorized kits, refer to Waltco documentation, and contact LiftGateMe (you can also email us at parts@liftgateme.com or call at (774) 266-8892) for part matching and tech support.