High Performance Ignition Coil for Buick Rainier (2005-2007) 5.3L

High-Output UF414 Ignition Coils for 2005-2007 Buick Rainier (LH6 / GMT360)

This 8-pack of UF414 performance ignition coils replaces the restrictive and degradation-prone factory units to restore lost voltage output, resolve persistent misfires under heavy load, and provide a stronger, more consistent spark for the 5.3L V8 engine.

The Stock GMT360 Ignition Weakness

The OEM ignition coils on the 5.3L LH6 engines are notoriously prone to thermal degradation over time. Positioned directly above the exhaust manifolds, these units suffer from severe heat soak cycles that break down internal epoxy resins and compromise primary winding insulation. This thermal fatigue leads to internal arcing, erratic secondary voltage delivery, and high-rpm misfires. When subjected to the increased engine loads of towing or steep inclines, the weakened factory coils fail to produce the necessary spark energy, triggering P0300-series OBD-II codes, causing sluggish throttle response, and drastically reducing fuel efficiency.

The Engineering Solution

Engineered to exceed OEM specifications, these UF414 upgrade coils utilize a high-capacity internal winding matrix and upgraded neodymium magnetic cores to significantly boost spark energy output. The external housings are constructed from high-dielectric epoxy and thermal-resistant polymers designed specifically to withstand the extreme underhood temperatures of the GMT360 chassis. By increasing the secondary voltage output and shortening the coil charge times (dwell), this comprehensive 8-pack ensures complete combustion even under heavy engine load. The improved spark duration directly translates to a stabilized idle, immediate throttle response, and the complete elimination of spark blowout during demanding towing conditions. Plug-and-play fitment ensures seamless integration with the factory wiring harness.

Technical Specifications

Compatibility

• 2005 Buick Rainier 5.3L V8
• 2006 Buick Rainier 5.3L V8
• 2007 Buick Rainier 5.3L V8

The Buick Utility Standard

For a truck-based SUV designed for genuine utility, reliable ignition is not optional. Upgrading to high-performance coils ensures your Rainier maintains the necessary low-end torque for towing and consistent power delivery for daily driving, keeping the heavy-duty LH6 running efficiently for the long haul without throwing frustrating misfire codes.