T-45 Transmission Overview
Designed by BorgWarner, the Ford T45 transmission (also known as the Tremac T45 transmission) is a five speed manual gearbox that was first introduced on the fourth generation Ford Mustang. The venerable Ford 5.0/302 V8 was replaced in 1996 by the now famous Ford Modular 4.6L V8, and Dearborn wanted a new transmission that was better suited for the new engine’s performance characteristics. The new Ford T-45 transmission was capable of handling up to 375 lb-ft of torque, thanks to a beefy 31-spline output shaft. And the carbon lined steel syncro rings ensured smooth shifting at speed. In 1997, a company known as TTC (Transmission Technologies Corporation) bought the Borg Warner Light-Duty Transmission business, and rebranded this gearbox as the Tremec T45. While this gearbox was produced from 1996-2001, there were three basic versions of it. The 1996-1998 Ford Mustang GT T45 transmission got an 8-tooth speedometer gear, while the 1996 – 1998 Ford Mustang Cobra T-45 transmission had a 7-tooth speedometer gear and the crossmember mount was further towards the rear, which necessitated a unique tail housing. In 1999, the Tremec T-45 transmission received a number of improvements that included a new OSS speedometer sending unit, a much stronger throwout bearing (remember, the horsepower increased significantly during these years), stronger shift forks, and carbon fiber Synchro rings for 3rd gear, 4th gear, 5th gear and Reverse.
What Transmission Do I Have?
OE T-45 5-speed Manual Transmission Applications
1996-1998 Ford Mustang GT 4.6L
1999-2001 Ford Mustang GT 4.6L (transmission code ‘6’)
1996-1998 Ford Mustang Cobra 4.6L
1999-2001 Ford Mustang Cobra 4.6L (transmission code ‘6’)
2001 Ford Mustang Bullitt 4.6L (early production with transmission code ‘6’)
T-45 Technical Specs
10.5” clutch
10-spine input shaft
31-spline output shaft
Single rail gear selector
Clutch housing is integrated with bell housing cover
Needle bearings under 1st-4th gears
Tapered roller bearings on main and countershafts
Clutch cable release fork pivot
Uses Ford Mercon V fluid
Common T-45 Transmission Problems
Fifth/reverse shift forks
1-4 shift forks
3-4 shift forks
Failed shift lugs
Input/release bearing
What Transmission Do I Have?
Conclusion: T-45 Transmission
While the Tremec T45 transmission bellhousing design limits its use to 1996 – 2010 Ford 4.6L and 2011 Ford 5.0L/5.4L applications, the Ford T-45 transmission is quite capable of handling high torque output, while delivering smooth shifting and long-term durability.
