Keep old wheel loaders producing

Categories: Transmissions

Rebuilt TT / TRT 2000 Series Transmissions

Is your old front-end wheel loader losing power or speed due to transmission issues? Catalyst Powertrain® can keep your old front-end wheel loader moving and in production with a rebuilt transmission.

Rebuilt Transmission vs New Equipment

While a transmission rebuild usually includes new items like seals, gaskets, and other parts, generally, the core gears and alignments stay intact and are tuned to your specific rig. A rebuilt transmission for an older heavy-duty vehicle can get your equipment back into production faster with optimal results and often at tremendous cost savings (10x and up) versus the cost of new equipment. Catalyst Powertrain rebuilds transmissions to original specifications, and every transmission is dyno tested under load prior to shipment.

The Allison / Twin Disc Twin Turbine (TT) series

This transmission is still used today in many diverse industrial applications. Originally manufactured by Allison Transmissions in the 1970s, these were in production for about a decade. Learn more about the Allison TT/TRT Series and check out the transmissions we have in stock here.

Technical details of the TT/TRT 2000 series

TT/TRT2000 Series Transmission

The TT series transmission incorporates a twin turbine converter, engine-driven PTOs, planetary gearing, hydraulic clutches, front and rear output, forward and reverse pressure taps, optional clutch cutoff or inching, and a provision for a neutral start switch.

The TT series transmissions have smooth, full power directional shifting capability (soft shift), and a 2-phase, 4-element converter with an automatic phase transition that has been successful in many vocations.

The TT2001 series powershift transmission is designed primarily for cycling vehicles and vocations.

Applications include:

  • Self-propelled cranes
  • Rail equipment
  • Winches
  • Material handling equipment
  • Logging
  • Agriculture

…and much more.

The TT/TRT transmissions series includes different model designations including:

  • TT1220-1
  • TT2220-1
  • TT2420-1
  • TT2221-1
  • TT2421-1
  • TRT2220-3
  • TRT2420-3
  • TRT2211-3
  • TRT2221-3
  • TRT2421-3

OEM Models using the TT/TRT 2000 series transmission

The most popular applications included front-end wheel loaders for OEMs such as John Deere, Case, Fiat Allis, Terex, Ford, and more.

John Deere

Here is a common wheel loader spec sheet (This example is the John Deer 644B spec sheet)

  • 444
  • 444A
  • 444B
  • 444C
  • 544
  • 544A
  • 544B
  • 544C
  • 544D
  • 644
  • 646
  • 644A
  • 644B
  • 644C
  • 644D
  • 646D
  • 646C


  • W18
  • W20
  • W20B
  • W20C
  • W20D
  • W24
  • W24B
  • W24C
  • W30


  • A62
  • A64
  • A66

Fiat Allis

  • 545
  • 545B
  • 645
  • 645B
  • 745
  • 705B
  • 945
  • 605B
  • FR10
  • FR20
  • FR15
  • FR12
  • FR30


  • 72-31
  • 72-21
  • 72-51
  • 72-61


  • 2000

Looking to keep your old front wheel loader in production? Give us a call at (800) 872-6691 for more information today on the TT series transmissions and parts or reach out about the TT series via the product page.