Product Description

Michigan Motorsports LS Rocker Arm Trunnion Upgrade Kit

Fits Most LS Rocker Arms Except LS7 | Captured Roller Bearing Trunnion Kit for LS1 LS2 LS3 LS6 L99 LSA LQ4 LQ9 4.8L 5.3L 5.7L 6.0L 6.2L Engines

Upgrade your factory LS rocker arms with the Michigan Motorsports LS Rocker Arm Trunnion Upgrade Kit. This retrofit kit is designed to convert stock LS-style rocker arms into captured roller bearing rocker arms for improved durability, smoother rotation, and better valvetrain stability at higher RPM. Factory LS rocker arms are lightweight and strong, but the original needle bearings are a known failure point that can send small bearings through the engine if they come apart. This Michigan Motorsports trunnion upgrade replaces the weak factory bearing setup with captured roller bearings, upgraded trunnions, retaining rings, and stronger bolts for a complete installation. Whether you are working on a stock 4.8L daily driver, a cammed LS street build, a supercharged setup, a turbo engine, or a 1,000+ horsepower race combination, this kit is a must-have reliability upgrade when using factory LS rocker arms.

Key Features & Benefits

• Converts Stock LS Rockers to Captured Roller Bearings: This retrofit trunnion kit upgrades factory LS rocker arms from the original loose needle bearing design to a captured roller bearing setup. The result is smoother rocker arm rotation, improved durability, and a more reliable valvetrain without the cost of full aftermarket roller rockers.
• Helps Prevent Common LS Rocker Bearing Failure: Factory LS rocker bearings are a known weak point, especially in higher-mileage engines or performance applications. When stock bearings fail, loose bearing debris can travel through the engine and cause serious damage. This kit helps eliminate that risk with a captured bearing upgrade.
• Built for Stock, Cammed & Power-Adder LS Builds: Highly recommended for engines with aftermarket camshafts, superchargers, turbochargers, nitrous, upgraded valve springs, or high-RPM use. Michigan Motorsports uses these trunnion kits in everything from stock 4.8L builds to 1,000+ horsepower turbo combinations.
• High-Strength Shorter Bolts Included: The included upgraded bolts are slightly shorter than factory hardware to prevent protrusion into the intake ports. These bolts are stronger than Grade 8 hardware with a minimum tensile strength of 170,000 psi, giving your upgraded rocker arm setup a stronger and cleaner installation.
• Cost-Effective LS Valvetrain Upgrade: Stock LS rocker arms are already strong and lightweight. Once upgraded with captured roller bearings and improved trunnions, they perform similarly to expensive aftermarket roller rockers at a fraction of the cost, making this one of the best-value upgrades for LS reliability.

Kit Includes

• (16) Rocker arm trunnions
• (32) Rocker arm bearings
• (33) Rocker arm retaining rings
• (16) Upgraded rocker arm bolts
• (2) Washers for pressing bearings
• Installation instructions

Important Installation Notes

• Installation Method: Installation can be completed with a press or a simple vise along with basic hand tools.
• Instructions Included: Instructions are included to help guide the trunnion kit installation process.
• Bolt Design: Included bolts are slightly shorter than factory bolts to prevent protrusion into the intake ports.
• Hardware Strength: Supplied bolts are stronger than Grade 8 with a minimum tensile strength of 170,000 psi.
• Bulk Ordering: Need multiple sets? Contact Michigan Motorsports for bulk purchasing options.

Notes

• Brand: Michigan Motorsports
• Application: LS rocker arm trunnion upgrade kit for most non-LS7 LS-style rocker arms.
• Upgrade Style: Captured roller bearing trunnion conversion for stock LS rocker arms.
• LS7 Note: LS7 7.0L applications should order Michigan Motorsports part number 55200.
• Recommended Use: Rocker arm bearing upgrade, valvetrain reliability improvement, aftermarket camshaft installs, supercharger builds, turbo builds, nitrous applications, high-RPM LS combinations, and preventive maintenance.

Key Fitments

• LS1 rocker arm applications
• LS2 rocker arm applications
• LS3 rocker arm applications
• LS6 rocker arm applications
• L99 rocker arm applications
• LS4 rocker arm applications
• LS9 rocker arm applications
• LSA rocker arm applications
• LQ4 rocker arm applications
• LQ9 rocker arm applications
• L76 rocker arm applications
• L92 rocker arm applications
• LR4 rocker arm applications
• LM7 rocker arm applications
• L59 rocker arm applications
• LM4 rocker arm applications
• L33 rocker arm applications
• L98 rocker arm applications
• L77 rocker arm applications
• LY6 rocker arm applications
• LFA rocker arm applications
• LZ1 rocker arm applications
• LY2 rocker arm applications
• L20 rocker arm applications
• LMF rocker arm applications
• LH6 rocker arm applications
• LY5 rocker arm applications
• LMG rocker arm applications
• LC9 rocker arm applications
• LH8 rocker arm applications
• 4.8L LS-based rocker arm applications
• 5.3L LS-based rocker arm applications
• 5.7L LS-based rocker arm applications
• 6.0L LS-based rocker arm applications
• 6.2L LS-based rocker arm applications
• Fitment note: Does not fit LS7; use Michigan Motorsports part number 55200 for LS7 applications.