T45 Transmission

Think of a manual transmission as a link or middleman between the engine and the wheels on your car. The motor transmits power through the tranny to reach the drive wheels. It is responsible for the speed and torque needed for your car to handle different driving conditions. In a vehicle with a manual unit, the driver shifts the gears using the pedals and clutch, while in an automatic type, the car does the work for you.

When you’re in first gear, you have lots of torque but not very high speed. This can help your car traverse up a hill using higher torque. On the other hand, the top gear (fifth or six gear) allows your car to reach high speeds, but you have a low wheel torque.

If you’ve driven a car with a manual unit, or if you’ve ridden in a manual transmission car, or if you’ve seen a decent action movie with a car chase scene (no one drives automatics in movies), then you have an idea about the clutch pedal and the gear shifter.

These are the two inputs by which a driver operates a manual tranny, though if we’re being technical the shifter is the only piece of this whole puzzle that is operated manually (i.e. by hand). Underneath all that is what appears to be an elaborate mechanism – a whirring array of shafts and gears that somehow translate into forward (or reversed) momentum.

What is a t45 transmission?

Though the T45 is frequently forgotten, it has some features that make it more desirable than an older T5. Similarly, though it was replaced by the TR3650 in short order, the T45 heralded in several important firsts for Mustangs.

Designed by BorgWarner, the Ford T45 (also known as the Tremec 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.

What is the difference between a t5 and t45 transmission?

The T-5 is one of the most respected, and long-lived, manual transmissions. Mustangs were first equipped with T-5 Transmissions in 1983 and continued using them for all V8 applications until the 1998 Mustang . The T-5 continued to be in use though, as the manual tranny of choice for V6 Mustangs until 2010. This durable unit lasted through the Fox Body, SN95, and S197 Mustang generations, longer than any other transmission, though by the end significant changes had been made to the T-5.

On the T45the bellhousing is part ofthe tranny itself, and the bolt pattern is different. Only the 2 upper bolts are in the same location. The rest and the dowel pins are NOT. The output shaft is 31 spline while theT5is 28.

How much does it cost to rebuild a t45 transmission?

Like all parts of the vehicle, the tranny wears out over time and needs repair or replacement.

Below is a list of the most common problems indicating that the unit is faulty:
  • When the neutral gear is engaged, the box makes a noise.
  • While driving, you can hear metal knocking or clatter from the side of the gearbox.
  • Shift problems occur when one gear engages, the other gear engages.

    A rebuild is a great option in most cases. This means you are only replacing the parts that have failed. Just like a replacement, you are fixing certain parts, but not doing it in a factory setting. You will want a very reputable repair shop to have this done.


    You may want to have a rebuild over a replacement because it can cost less because it is not done on the factory level. Also, oftentimes it is known that having it done in a factory setting does not necessarily mean that all the parts are brand new from the manufacturer. You are simply having a different type of mechanic replacing the parts. In most cases, brand new transmissions are only done when new cars are produced.

    A rebuild replaces only those parts of a vehicle’s transmission that are severely worn or damaged, thus eliminating the overkill that results from replacing a transmission that is still in good shape, save for the broken or worn parts, with a new unit. A properly rebuilt T45 is going to run you $1000 plus, depending on what performance parts you want in it.

    How much HP can a t45 handle?

    With the introduction of the mod motor 4.6L in 1996 came the introduction of the T-45 5-speed manual transmission. All Mustangs equipped with this transmission use a 10.5″ clutch. The T45 shares many attributes with the T56, so it is a strong transmission. Its weak link is the 10-spline input shaft which limits power handling.

    • 1996-98 Mustang GT T45 transmissions had an 8-tooth speedometer sensor drive gear and a forward located transmission mount.
    • 1996-1998 Mustang Cobra transmissions had a 7-tooth speedometer sensor drive gear and a rearward located transmission mount.
    • 1999-2001 Mustang GT and Cobra transmissions used an electronic pickup “hall-effect” sensor for the speedometer signal and all had the rearward located transmission mount.
    • 1996-01 T45 transmissions use the exact same shifter as the T5. The 1-2 shift fork is shared between all 96-01 T45s. The 3-4 shift fork was updated in 1998 through 2001 and is a common upgrade for 1996-97. The reverse fork was also updated in 1998 and there are three different versions available.

      Speaking of reverse, the T45 was the first Mustang transmission to feature a fully synchronized reverse gear. All T45 varieties use a ribbed aluminum case with integral bell housing. T45 can handle as much as 650 HP.

      Editorial Staff

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