Holley Lower Structure Support

2003 and Up Gen III Hemi Engines 5.7L, 6.1L, 6.2L, 6.4L

302-65

Overview:

The Holley Lower Structure Support is a precision-engineered component designed specifically for Gen III Hemi engines from 2003 and newer, covering popular displacements from 5.7L to 6.4L. This support bracket enhances the structural integrity between the engine block and transmission or bellhousing, replicating the factory design found on late-model oil pans. It is an essential upgrade for enthusiasts performing engine swaps or using aftermarket oil pans that lack the OEM-style transmission mounting points.

By bolting the engine block directly to the transmission or bellhousing, this support adds critical driveline strength, reduces vibration and noise, and protects driveline components from dirt and debris. It is compatible with a wide range of factory and swap oil pans as well as numerous common transmissions, making it a versatile solution for Gen III Hemi builds.

Key Features:

This lower structure support offers multiple benefits that improve durability and drivability for Gen III Hemi-powered vehicles:

• Bolts engine block to transmission or bellhousing for enhanced driveline strength and support
• Provides OEM-style fitment on oil pans that do not have transmission mounting points
• Compatible with cast, fabricated, and stamped swap oil pans including Holley PN 302-60, 302-61, 302-64, 302-64BK, 5050WND, 5051WND, WB11010, and stamped steel factory pans
• Fits all Gen III Hemi engines from 2003 and up: 5.7L, 6.1L, 6.2L, and 6.4L variants
• Works with a broad range of transmissions such as TR-6060, NAG1, 545RFE, 8HP70, 8HP90, 9HP75, A727, 46RE, 46RH, and more
• Compatible with Lakewood bellhousings LK7000 and LK7000K for Mopar 3-speed, 4-speed, or Tremec TKO/TKX transmissions
• Covers the lower portion of the bellhousing to prevent dirt intrusion and protect driveline components
• Reduces vibration and noise for a smoother driving experience
• Rigid cast aluminum construction with a natural as-cast finish for durability and corrosion resistance
• Includes all necessary hardware for straightforward installation over existing oil pans

Construction & Design:

The Holley Lower Structure Support is crafted from high-quality cast aluminum, chosen for its excellent strength-to-weight ratio and resistance to corrosion. The natural as-cast finish provides a durable surface that withstands harsh undercar conditions without requiring additional coatings. Its rigid design ensures maximum support between the engine block and transmission or bellhousing, effectively reducing flex and improving drivetrain longevity.

Engineered to fit a variety of oil pans and transmissions, this support bracket maintains precise OEM-style alignment, ensuring compatibility and ease of installation without the need for modifications or custom fabrication.

Installation & Fitment:

Installation is straightforward and designed to bolt directly onto existing oil pans using the included fasteners. This eliminates the need for welding or complex modifications. The support fits a wide range of Gen III Hemi engines from 2003 onward, including 5.7L, 6.1L, 6.2L, and 6.4L displacements. It is compatible with numerous transmissions and bellhousings commonly used in swaps and performance builds, making it a versatile choice for engine and transmission combinations.

By adding this support, installers can replicate the factory strength and alignment found on late-model oil pans that bolt to both the engine and transmission, enhancing driveline stability and reducing noise and vibration.

What's Included:

• Holley Lower Structure Support bracket (cast aluminum)
• Complete hardware kit for mounting to engine block and transmission or bellhousing
• Installation instructions

Ideal For:

This product is ideal for automotive enthusiasts, engine builders, and professional mechanics performing Gen III Hemi engine swaps or upgrades. It is especially beneficial for those using aftermarket or swap oil pans that lack transmission mounting points, as well as anyone seeking to improve driveline strength, reduce vibration, and protect transmission components from dirt and debris. Whether building a street performance vehicle, race car, or custom project, this support bracket ensures reliable and durable engine-to-transmission integration.

Holley is a cornerstone name in performance, spanning everything from classic carburetion to modern EFI, fuel systems, and race-ready supporting components. It’s also home to a roster of iconic sub-brands across ignition, exhaust, and drivetrain—making Holley a one-stop ecosystem for builders chasing better drivability, more power, and proven track heritage.