Choosing the right motor mounts is essential when swapping an LS family engine into classic OBS and square body trucks. The mounts below are designed to support a range of transmissions, align engine placement, and fit popular Chevy/GMC platforms from 1973 to 1998. This guide highlights five top options with features, helping you balance fit, durability, and install ease for a solid LS conversion project.
| Product | Brand | Compatibility Highlights |
|---|---|---|
| LS Swap Motor Mounts Compatible with 1973-1998 Square Body / OBS | Goopool | Supports various transmissions; fits C10/C/K series |
| for LS Swap Motor Mounts Adapter Plates – Universal Swap Bracket | Yoursme | Bolts LS into small-block Chevy origins; centerline shift |
| Full Engine Mount Adapter Plates Urethane Swap Kit | YHB | Multi-vehicle fit; laser-cut steel; 1/4″ plates included |
| maXpeedingrods LS Engine Swap Mount Adapter Kit | maXpeedingrods | G-Body 1973-1988; LS1/LS2/LS3/LS6 compatibility |
| IRENPORU LS Swap Motor Mount Compatible with 1973-1998 Square Body | IRENPORU | OBS and Square Body; adjustable engine placement |
Goopool LS Swap Motor Mounts
Goopool’s LS Swap Motor Mounts are designed for 1973-1998 OBS and square body Chevy/GMC trucks, including 2WD and 4WD configurations. The mounts feature adjustable slots to position the engine within the compartment, aiding fitment for a wide range of transmissions, such as 4L60E, 4L65E, TH350, TH400, TH700R4, and 4L80. They accommodate all Chevrolet LS engines (LS1, LS2, LS3, LS6, LS7, LS9) and common Vortec truck engines (4.8L, 5.3L, 5.7L, 6.0L, 6.2L from 1997-2014, plus 1999-2013 variants). This flexibility supports manual and automatic transmissions, ensuring broad compatibility for LS swaps into classic trucks and the C/K lineup.
The design emphasizes engine placement control and robust mounting surfaces, enabling stable performance under varied driving conditions. Installation requires attention to the vehicle’s chassis and transmission cross-members, but the adjustable nature helps mitigate clearance issues with headers and exhaust. If you’re building a reliable LS swap for a classic pickup, Goopool provides a versatile, broadly compatible mounting option.
Yoursme LS Swap Mount Adapter Plates
Yoursme offers universal LS adapter plates designed to bolt an LS engine into vehicles originally equipped with a small-block Chevy. The design moves the crankshaft centerline up by 0.17 inches to optimize alignment and fit. The package includes two adapter plates, eight flat head bolts, and a set of flange M10-1.5 bolts, providing a complete hardware kit for a straightforward install. These plates are crafted to OEM-like specifications for solid fitment and stability during operation.
Ideal for builders seeking a relatively simple installation with adjustable positioning, these brackets emphasize a balance of strength and precision. They are suitable for a broad spectrum of LS engines, including LS1, LS2, LS3, LS6, LQ4, and LQ9, making them a practical choice for various LS swap projects in classic American trucks and muscle cars alike. While not a premium billet solution, the design offers reliable alignment and straightforward assembly.
YHB Full Engine Mount Adapter Plates Kit
YHB provides a urethane swap kit featuring full engine mount adapter plates with a laser-cut, multi-position design for enhanced durability. The kit is compatible with a wide range of 1983-2005 GM-based SUVs and pickups, including S10/Sonoma, S15, Blazer, Jimmy, and related models. The set includes mounting bolts, washers, nuts, and four motor mount plates, eliminating the need for separate hardware in most installs. The combination of steel construction and urethane makes it suitable for challenges associated with aggressive power adders and frequent engine swaps.
With a focus on rigid mounting and long-term stability, this kit supports LS engines with a broad compatibility footprint. It’s a strong option for builders who want a reliable, ready-to-install solution for mid-size GM trucks and SUVs, particularly when upgrading the drivetrain with an LS-based powerplant. The kit’s comprehensive hardware set simplifies the installation process and reduces the need for aftermarket components.
maXpeedingrods LS Engine Swap Mount Kit
The maXpeedingrods kit targets G-Body platforms from 1973-1988, including popular cars like the Monte Carlo. It supports LS1, LS2, LS3, LS6, and LSX engines, as well as common LS-based powertrains such as LQ4 and LQ9. The kit emphasizes ease of installation with specially treated spacers to resist corrosion and provide reliable alignment. This makes it a practical choice for traditional GM chassis swaps where precise engine positioning is essential for hood clearance, headers, and accessory belts.
Engineers designed this kit to accommodate a range of LS variations and engine mounts, aiding fitment in conversions where space is tight or where a custom shroud, radiator, or exhaust routing must be considered. The kit’s emphasis on durable spacers and precise tolerances helps ensure consistent performance and reduced vibration, contributing to a clean, efficient LS swap in classic G-Body vehicles.
IRENPORU LS Swap Motor Mounts
IRENPORU offers adjustable LS swap motor mounts designed for 1973-1998 OBS and square body Chevy/GMC trucks. These mounts support both 2WD and 4WD configurations and claim broad engine compatibility across LS engine variants, including LS1, LS2, LS3, LS6, LS7, and LS9, as well as common Vortec engines. They accommodate a full range of transmissions, such as 4L60E/4L65E and TH-series units, with adjustable mounting to help achieve the correct engine position within the engine bay.
This option emphasizes versatility and alignment control, allowing enthusiasts to tailor engine placement to their specific chassis and exhaust routing needs. If you are retrofitting a classic GM truck with a modern LS engine and require precise alignment to heavy-duty transmissions, IRENPORU’s mount kit presents a flexible and adaptable solution.
Buying Guide: Key Considerations For LS Swap Motor Mounts
- Engine compatibility: Verify which LS variants are supported (LS1/LS2/LS3/LS6/LS7/LS9, LQ4/LQ9, etc.) and ensure the mount works with your specific LS engine family.
- Transmission compatibility: Check that the mounts accommodate your planned transmission (manual or automatic) and that the adapter plates or mounting slots align with the transmission cross-member and bellhousing.
- Engine placement and clearance: Look for adjustable slots or multi-position designs to optimize crankshaft centerline, hood clearance, exhaust headers, and radiator fit.
- Material and durability: Aluminum or steel options affect weight and strength. Laser-cut plates and urethane or solid mounts often offer better longevity and vibration control.
- Hardware and installation: Assess whether the kit includes all necessary bolts, washers, and nuts. A complete hardware set simplifies install and reduces misfit risks.
- Vehicle compatibility: Confirm fitment for the target chassis (OBS trucks, C/K series, Jimmy/Sierra/Sonoma line) and verify wheelbase, frame rails, and cross-members align with the new engine setup.
- Future servicing and upgrades: Consider ease of future maintenance, availability of replacement parts, and whether the mounts allow for easy engine access or removal.
- Warranty and support: Check vendor warranties and whether they provide technical support for common swap challenges, such as fuel lines, exhaust routing, and accessory belt alignment.
- Cost versus performance: Balance price with expected durability, alignment precision, and ease of install. Higher-end billet options may offer tighter tolerances but at a higher upfront cost.
- Installation skill level: Some mounts require more fabrication or alignment time. Assess whether you’ll install them yourself or hire a professional for precise positioning and alignment checks.