The back half frame kit is a popular upgrade for Jeep owners and classic GM vehicle enthusiasts who want improved departure angles, increased ground clearance, and a strong mounting base for new bumper setups. This guide highlights five top options, summarizing key features, fitment, and installation notes to help you choose the right kit for your project. Each option is evaluated for durability, compatibility, and how it supports common off-road and performance goals.
| Product | Vehicle Compatibility | Material | Key Benefit |
|---|---|---|---|
| Back Half Frame Kit for Jeep TJ | Jeep TJ | 3/16″ high-strength steel | Sturdy rear frame and bumper integration |
| JEGS Transmission Double-Hump Crossmember | GM G-body with TH-400 | Powder-coated steel | Dual exhaust upgrade compatibility |
| Back Half Frame Kit for Jeep YJ | Jeep YJ 1987-1995 | 3/16″ steel | Enhanced rear departure angle |
| Back Half Frame Kit with Standard Bumper for 04-06 Jeep LJ | Jeep LJ 2004-2006 | 3/16″ high-strength steel | Includes wide rear bumper and rigid mounts |
| Artec Industries Back Half Frame Kit (TJ/YJ) | TJ and YJ | Standard steel (industrial) | Compact packaged option from a recognized name |
Below are five detailed product sections that explain what each kit brings to the table, how it’s typically installed, and where it shines. The buying guide at the end covers considerations like weldability, bumper compatibility, and installation expertise to help you align your project goals with the right back half frame kit.
Back Half Frame Kit For Jeep TJ
This TJ frame back half kit is designed specifically for Jeep TJ models, delivering a robust transformation of the rear frame. Fabricated from 3/16 inch high-strength steel plate, the kit features press-brake formed components for precise fitment and structural integrity. It includes 3/4 inch thick high-strength steel plate D-ring mounts and two lower and two upper frame rail sections, enabling a modular install during the mock-up stage. A complete rear bumper assembly with 3/4 inch D-ring mounts and end caps is included to finish the look. This kit is intended for users planning a comprehensive rear-end upgrade and a new bumper system, with welding-centric installation. The included end caps are welded in place to attach the bumper, so expect professional mounting of the bumper as part of the final assembly.
Key considerations: durability under off-road stress, compatibility with aftermarket bumpers, and the level of fabrication skill required. It’s best suited for builders who want a reinforced, integrated rear frame with a dedicated bumper mount system and a clean welded finish. Moderately experienced welders will find the kit workable, though the mock-up stage is essential to ensure precise alignment with body lines and bumper mounting points.
JEGS Transmission Double-Hump Crossmember
The JEGS crossmember focuses on drivetrain compatibility, featuring a double-hump design that supports dual exhaust configurations. While not a traditional back-half frame kit, this component is frequently part of broader rear-drive-train and chassis upgrades for GM G-body applications with TH-400 transmissions. The crossmember provides stable mounting points and helps realign exhaust routing while maintaining chassis rigidity. The item is black powder coated for corrosion resistance and wear resistance, making it a practical upgrade for daily drivers and weekend warriors who want better clearance around the transmission area without sacrificing strength.
Considerations: verify compatibility with your specific GM G-body chassis and exhaust layout. The crossmember is tailored for TH-400 transmissions, so ensure your drivetrain matches this specification. This piece is best for builders addressing transmission support, exhaust routing, and rigidity as part of a back-end chassis refresh rather than a full rear frame replacement.
Back Half Frame Kit For Jeep YJ
The YJ back half kit is designed for older Jeep models from 1987 to 1995. It moves the frame rails rearward under the rear floor, which improves departure angle and adds rear clearance. The kit is laser-cut from 3/16 inch steel plate, providing a strong foundation for a heavy-duty bumper and suspension work. It includes a built-in rear bumper option and provides a clean mounting location for air bump stops, simplifying the installation for a more aggressive off-road setup. Sold as a complete kit, it’s aimed at enthusiasts who want a solid, straightforward path to rear-end enhancement with clear mounting points.
Installation notes: ensure the rear frame geometry aligns with the existing body mounts and the bumper system you plan to run. This kit is well-suited for capable off-road builds where the user intends to maintain solid mounting surfaces and improve rear geometry. Welding and alignment accuracy are important for fitment and performance.
Back Half Frame Kit With Standard Bumper For 04-06 Jeep LJ
This LJ-specific back half kit integrates a 50-inch wide bumper into the rear end, expanding the compatibility for larger bumper systems and accessories. Constructed from 3/16 inch high-strength steel with press-brake formed components, the kit includes two lower frame rails and two upper frame rails designed to be joined during mock-up assembly. The bumper assembly uses 3/4 inch thick D-ring mounts, with end caps welded in place to attach the rear bumper. A notable note for this setup is its compatibility caveat: it does not work with the factory gas tank, and adjustments in the fuel system or fuel cell installation may be required. Also, the factory coil springs are not compatible with this kit, signaling a more advanced build intent and space considerations for suspension upgrades.
Best use cases include more extensive rear-end transformations where space, bumper width, and heavy-duty mounting are priorities. Expect an experienced welder/fabricator to execute this installation due to the precision and welding requirements involved in creating a clean, durable rear end finish.
Artec Industries Back Half Frame Kit (TJ/YJ)
The Artec Industries back half frame kit offers a compact, practical option for TJ and YJ models. The product page lists package dimensions and weight, with a single item per package. While the features provided are concise, Artec Industries is known for offering performance-focused off-road components designed to fit a straightforward installation workflow. The TJ/YJ compatibility indicates a flexible approach suitable for owners seeking a strong rear-end upgrade without overly extensive modifications. This kit is a good match for those who want a reliable backbone for a rugged bumper setup while balancing ease of installation with durability.
Installation considerations: verify the exact fitment for your specific TJ or YJ frame and confirm bumper compatibility. Since the listing emphasizes packaging details, buyers should confirm assembly instructions and welding needs with the seller or a professional fabricator.
Buying Guide: Key Purchase Considerations For Back Half Frame Kits
When selecting a back half frame kit, consider these factors to ensure the upgrade meets your goals and vehicle constraints:
- Vehicle compatibility: verify model, year range, and any factory components that could affect fitment, such as gas tanks or factory suspensions.
- Material and construction: 3/16 inch steel is common for frame rails; assess whether press-brake formed parts and thick bumper mounts align with your expected level of off-road use and load.
- Bumper and mounting hardware: ensure the kit includes or supports compatible bumper systems, D-ring mounts, and end caps for a clean finish.
- Welding and installation difficulty: some kits require professional welding and alignment; others offer more straightforward bolt-in or mock-up assembly steps.
- Ground clearance and geometry: evaluate how the kit affects departure angle, rear clearance, and suspension travel, especially if upgrading springs or shocks.
- Exhaust and drivetrain considerations: for GM crossmembers, confirm transmission and exhaust compatibility to avoid conflicts with new routing.
- Future upgrades: plan for how the kit will work with your intended bumper, fuel system, and suspension setup to prevent mismatches down the line.
In summary, the best back half frame kit for your project hinges on your vehicle, the level of fabrication you’re comfortable with, and how you intend to use the vehicle. For Jeep TJ and YJ builds, several kits emphasize integrated bumpers and robust frame rails to support aggressive off-road use. For GM builds, components like crossmembers address drivetrain alignment and exhaust routing as part of a broader chassis upgrade. Always confirm fitment with the seller and, if possible, consult a qualified fabricator to ensure optimal durability and performance.