TREMEC Magnum XL GM 6-Speed Close Ratio Transmission – TUET18131 (0.63 6th Gear)

Built for Modern GM Performance. Engineered for Precision Shifting.

Meet the TREMEC Magnum XL TUET18131, the long-awaited close-ratio 6-speed manual transmission tailored for modern GM performance platforms. Designed to meet the demands of today’s high-powered builds, this transmission delivers track-ready strength, race-inspired shift feel, and refined street manners—all in one complete package.

Based on the proven TR-6060 architecture, the Magnum XL GM variant offers enhanced features for modern applications, including a rearward shifter location, direct-mount design, and an advanced shifter isolator for exceptional NVH control. The result? A crisp, precise shift feel without sacrificing daily driveability.

Close-Ratio Gear Set Optimized for Performance:

• 1st: 2.66
• 2nd: 1.78
• 3rd: 1.30
• 4th: 1.00
• 5th: 0.80
• 6th: 0.63 (Fuel-saving overdrive)
• Reverse: 2.90

Key Features:

• GM-Specific Magnum XL 6-Speed Manual Transmission
• Rearward Shifter Location – Over 8" farther back than standard Magnum for modern chassis compatibility
• Direct-Mount Shifter – Eliminates sloppy feel from semi-remote systems
• Unique Shift Isolator – Reduces NVH while maintaining sharp, confident shifts
• Rated for 700 lb-ft of Torque – Built to handle serious power
• Supports Shifts at up to 7800 RPM – Perfect for high-revving engines
• Extended Tail Housing – Designed to fit modern GM performance builds

Why Choose the TREMEC Magnum XL TUET18131?

If you're running a modern GM-based powertrain and want a manual transmission that offers both strength and shift precision, the TUET18131 is built for you. The close-ratio gearing delivers quick acceleration and keeps your engine in its sweet spot, while the 0.63 6th gear provides low-RPM cruising on the highway.

Unlike typical bolt-on upgrades, the Magnum XL's purpose-built design eliminates the compromises of factory-style semi-remote shifters, giving you better feedback, faster engagement, and increased confidence in every shift.

Shift Like You Mean It. Drive Without Compromise.

Whether you're building a street machine, track weapon, or pro-touring project, the TREMEC Magnum XL TUET18131 offers the performance, durability, and refinement serious builders demand.

Ideal For:

• GM-based performance projects
• LS, LT, or other high-output engine platforms
• Restomods & custom builds
• Manual transmission swaps or upgrades
• High-RPM, high-torque driving environments

 

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