Choosing the right transmission for an LS engine swap is essential for fit, reliability, and performance. This guide highlights five popular options that are frequently chosen for classic GM builds, street cars, and project trucks. Each entry includes mounting hardware, crossmembers, and adapter details to help you compare compatibility and installation needs. Use the product summaries below to match your vehicle, transmission, and mounting preferences before diving into installation steps.
| Product | Brand | Key Feature |
|---|---|---|
| Trans-Dapt Performance Ls Engine Swap Mount Kit | Trans-Dapt | |
| Trans-Dapt Transmission Crossmember for 1982-2004 Chevy S10/GMC S15 | Trans-Dapt | |
| Trans-Dapt Performance – Transmission CROSSMEMBER; LS INTO 78-88 GM A & G-Body Cars | Trans-Dapt | |
| 1955-57 Chevy Tri-5 LS Swap Kit | Speedway Motors | |
| Gen III GM LS V8 to TH350/700R4 Trans Adapter Kit | Speedway Motors |
Trans-Dapt Performance Ls Engine Swap Mount Kit
The Trans-Dapt LS Engine Swap Mount Kit provides bolt-in engine mounts designed for swapping Chevrolet LS series engines. The kit includes essential mounting components and a frame-mitted layout that aligns the LS block with factory mounting holes. Vehicle compatibility centers on typical GM platforms capable of accepting LS blocks, simplifying the initial installation phase for builders seeking a straightforward mounting solution. The kit’s durable construction helps minimize engine movement, contributing to stable alignment during road use.
Trans-Dapt Transmission Crossmember for 1982-2004 Chevy S10/GMC S15
This crossmember is designed for LS engine swaps in 1982-2004 Chevy S10 and GMC S15 pickups, supporting 4L60E and 4L70E transmissions. It provides a robust mounting point that aligns with the LS drivetrain, reducing installation guesswork. The product is marketed as a direct attachment solution, helping to streamline the swap process for mid-size trucks while maintaining chassis geometry and driveline alignment. Availability of related hardware can further aid in completing a solid, long-lasting installation.
Trans-Dapt Performance – Transmission CROSSMEMBER; LS Into 78-88 GM A & G-Body Cars
This crossmember targets LS swaps into 1978-1988 GM A and G-body cars, offering a compatible mounting surface with engine and transmission brackets. The kit typically includes crossmember hardware and mounting pads to adapt the LS setup to the original frame. For builds aiming to preserve factory alignment while upgrading to an LS powerplant, this solution emphasizes a balanced approach to fitment and stability without extensive fabrication.
1955-57 Chevy Tri-5 LS Swap Kit
This Tri-5 LS swap kit offers a bolt-in engine mount system and a dedicated crossmember designed for the iconic 1955-57 Chevrolet models. The kit is constructed from 7-gauge steel with 3/8-inch adapters and polyurethane mounts, delivering a sturdy foundation for LS power within a classic Tri-5 chassis. The package emphasizes straightforward alignment by leveraging factory frame rivet holes, reducing fabrication steps for a cleaner install on these revered vehicles.
Gen III GM LS V8 to TH350/700R4 Trans Adapter Kit
The Gen III GM LS V8 to TH350/700R4 adapter kit provides a bridge between LS engines and older GM automatics. It includes a flexplate, flywheel bolts, adapter sleeve, torque converter bolts, and engine swap brackets. The flexplate is designed with a robust centerplate and precise tolerances to ensure alignment with modern LS crankshafts and older transmissions. This kit is suited for builders integrating older automatics with modern LS power, offering a coherent path to driveline compatibility.
Trans-Dapt Performance 4201 LS Engine Swap Mount Kit
The Trans-Dapt 4201 LS Engine Swap Mount Kit is designed for 67-69 Camaro (F-Body) and 68-74 Nova (X-Body) configurations, featuring rubber-pad mounts to reduce engine vibration while maintaining a solid connection to the frame. This kit targets classic GM F- and X-body builds pursuing an LS upgrade without extensive frame modification. The rubber pad design aims to balance durability with a comfortable, road-ready ride quality for older muscle and pony cars.
Buying Guide
- Vehicle compatibility: Match the kit to your model year and body style. Some kits are targeted at specific generations (A-, G-, or F-body) while others cover broader LS swap scenarios.
- Mounting hardware: Check whether the kit includes all necessary bolts, brackets, and adapters. Missing hardware can延 delay the swap.
- Crossmembers and adapters: A solid crossmember preserves driveline alignment. Adapters may be needed to connect an LS engine to older transmissions.
- Engine compatibility: Ensure the LS generation (Gen I/II/III/IV) aligns with your target transmission and vehicle frame geometry.
- Installation complexity: Bolt-in systems reduce fabrication, but some swaps require welding or trimming. Consider your skill level and available tools.
- Vibration and ride quality: Rubber or poly mounts influence vibration isolation and engine movement. Choose based on desired balance of comfort and stiffness.
- Parts sourcing: If a kit lists included components (crossmembers, pads, frames), verify availability of compatible hardware from the same line to avoid mismatches.
- Future maintenance: Consider ease of access for maintenance, inspection, and potential future upgrades when choosing a kit.
- Budget and comprehensiveness: Some kits are “bare bones” while others include flexplates, bolts, and brackets. Weigh long-term cost against upfront purchase.
- Orientation and alignment: Ensure the kit supports proper driveline angles and driveshaft alignment to prevent vibration and wear.