Tremec TUKT16901 T56 Magnum XL 6-Speed Transmission Ford 2.66 1st

The TUKT16901 is a close-ratio T56 Magnum XL for 2005-and-later Ford Mustangs, built with tighter gearing than TREMEC's wide-ratio Mustang version, with a 2.66 first gear and torque capacity reaching 700 lb-ft at engine speeds to 7,800 rpm; fifth and sixth gear ratios land at 0.80 and 0.63, the same double-overdrive spread used across the Magnum range.

Built to handle big power

A reinforced, one-piece countershaft is built to support naturally aspirated, supercharged, turbocharged, and stroker Mustang combinations, inside a lightweight, high-strength aluminum case at roughly 150 lbs. The extended-length XL tail housing again positions the shifter at the factory Mustang location, using a direct-mount, isolated shifter rather than the stock semi-remote design.

Shaft sizes and what is included

The input shaft carries 26 splines and the output 31, needing roughly 3.66 quarts of fluid to fill; TREMEC names HP-MTF, a Synchromesh-type product, or Dexron III ATF as acceptable choices. This version ships with the bellhousing, crossmember, transmission mount, and shifter handle included, so most of the mounting hardware comes with the transmission rather than being sourced separately.

What is the difference between this and the wide-ratio Magnum XL? This is the close-ratio version, built with a tighter first gear than the wide-ratio Mustang unit, which suits builds wanting quicker gear-to-gear acceleration over outright low-gear pull.

Does it include the crossmember and mount? Yes, both are included, along with the bellhousing and shifter handle.