JULY 4, 2025

Thieman TT15 Platform Comparison Guide: Steel vs. Aluminum, One-Piece vs. Two-Piece

Choosing the right pickup truck liftgate platform is about more than just size — it involves balancing material durability, weight, foldability, and vehicle compatibility. The Thieman TT15 series offers a range of platform configurations to fit your truck’s workflow. In this guide, we’ll compare steel vs. aluminum materials and one-piece vs. two-piece styles, while also exploring torsion assist functionality, platform sizes, and the real-world impact of platform weight.

• Documentation Resources from Thieman
• Steel vs. Aluminum Platform Construction
• One-Piece vs. Two-Piece Platform Functionality
• Torsion Assist Feature: What It Does and Which Platforms Have It
• Weight Differences and Impact on Fuel Efficiency and Load Capacity
• Choosing the Right Platform Size (26”, 32”, 42”, 44”)
• Which Platforms Include the Two-Piece Bumper
• Conclusion

Documentation Resources from Thieman

Information in this article is sourced exclusively from Thieman's official TT15 series documentation. Always refer to your specific liftgate’s manuals for serial number, model, and vehicle-specific procedures.

Reference PDFs Used:

• Thieman Liftgate TT-15 Owners Manual
• Thieman Liftgate TT-15 Brochure
• Thieman Liftgate TT-15 Parts List & Owners Manual
• Thieman Liftgate TT-15 Installation Manual
• Thieman Liftgate Rear Camera Kit (KIT-235)
• Thieman Liftgate Remote Control Pendant (KIT-179)
• Thieman Liftgate Cab Cutoff Switch (KIT-131)

Steel vs. Aluminum Platform Construction

(Source: thieman-liftgate-brochure-TT15-LIT.pdf)

Steel and aluminum are both available in the TT15 platform lineup, each suited for different work environments. Steel platforms use a heavy-duty diamond plate design, ideal for rugged commercial settings. Aluminum platforms, by contrast, use extruded construction, offering a lighter option without sacrificing strength.

Aluminum models significantly reduce liftgate weight. For example, a 56" x 26" steel one-piece platform weighs approximately 522 lbs, while the same size in aluminum is only 480 lbs — a 42 lb difference (thieman-liftgate-brochure-TT15-LIT.pdf).

For users operating in corrosive environments or looking to maximize fuel efficiency, aluminum lift gate platforms may be the better long-term investment. However, steel platforms remain a popular choice for heavy-duty performance and impact resistance.

One-Piece vs. Two-Piece Platform Functionality

(Source: thieman-liftgate-owners-manual-TT15-OM.pdf)

The TT15 series is offered in both one-piece and two-piece platform options. One-piece platforms provide a solid surface from the truck bed to the ground, ideal for loading pallets or equipment with wide bases. Two-piece designs, by contrast, offer easier manual folding and unfolding, especially when paired with torsion assist.

Each platform type — whether one-piece or two-piece — is available in steel or aluminum, and in various widths (49", 53", 56") and depths (26", 32", 42", 44") (thieman-liftgate-owners-manual-TT15-OM.pdf, parts list pages 14–21). The 2-piece aluminum platforms are often selected for applications requiring easier handling, especially in colder weather where platform folding can become more difficult.

Torsion Assist Feature: What It Does and Which Platforms Have It

(Source: thieman-liftgate-brochure-TT15-LIT.pdf and thieman-liftgate-owners-manual-TT15-OM.pdf)

Torsion assist is a built-in mechanical aid that helps users manually fold and unfold the platform with less physical effort. This feature is standard on all 42" deep steel and 44" deep aluminum two-piece platforms.

If your liftgate platform is difficult to fold or unfold, it may be a sign the torsion bar is broken or improperly tensioned (thieman-liftgate-owners-manual-TT15-OM.pdf, pg. 10). Thieman provides adjustment guidance in the maintenance section, including how to increase or decrease torsion force depending on user preference and platform size.

Weight Differences and Impact on Fuel Efficiency and Load Capacity

(Source: thieman-liftgate-brochure-TT15-LIT.pdf)

Weight isn't just about ease of installation — it affects the total payload your truck can carry and your fuel consumption over time. Here's a comparison of approximate installation weights from the Thieman brochure:

• TT15-5642 Steel 2PC: 670 lbs
• TT15-5644 Aluminum 2PC: 550 lbs

That’s a 120 lb difference between similar-sized platforms (thieman-liftgate-brochure-TT15-LIT.pdf).

In scenarios where payload efficiency is critical — such as delivery trucks with strict weight limits — shaving off those pounds with an aluminum platform can provide real operational value.

Choosing the Right Platform Size (26”, 32”, 42”, 44”)

(Source: thieman-liftgate-brochure-TT15-LIT.pdf)

Thieman TT15 platforms come in four main depths: 26”, 32”, 42”, and 44”. Choosing the right depth depends on what you’re hauling and how you load it:

• 26" depth: Common for basic cargo and standard deliveries.
• 32" depth: Offers a bit more room while keeping weight lower.
• 42" depth: Requires torsion assist (steel models only).
• 44" depth: Standard with torsion assist (aluminum models).

Platform depth also affects the effective pickup tailgate lift footprint. Larger platforms provide a broader area to stabilize cargo but add weight. Shorter platforms are lighter but limit larger palletized goods. Your ideal setup should match both your cargo size and physical loading space.

Which Platforms Include the Two-Piece Bumper

(Source: thieman-liftgate-brochure-TT15-LIT.pdf)

The Thieman TT15 platform usually includes a standard two-piece bumper. This design is especially helpful on deeper platforms like the 42" steel and 44" aluminum options, where clearance is needed for frame-mounted receiver hitches on modern pickups.

The two-piece bumper not only allows for easier access to hitch receivers but also simplifies the integration of optional accessories such as light kits and OEM camera/sensor relocation kits. This makes it a practical feature for customers equipping a pickup truck with liftgate who need full functionality without sacrificing towing capability or safety systems.

Conclusion

Selecting the right Thieman TT15 platform involves more than just picking steel or aluminum. One-piece and two-piece configurations, torsion assist availability, platform weight, and size all contribute to how your pickup truck liftgate performs in daily use.

For maximum durability, steel may be the answer. For lighter payloads and corrosion resistance, aluminum shines. If easy manual handling is a priority, torsion-assist-equipped two-piece platforms offer real ergonomic benefits. And don’t overlook the fuel and payload implications of your platform’s weight.

Whether you're outfitting a pickup with liftgate for light deliveries or need a rugged lift gate for pickup truck work in harsh environments, Thieman's TT15 series offers a tailored fit.