Used semi truck transmissions
Used Commercial Truck Transmissions for Sale
Tell us the truck, the transmission make and the tag number. We'll search for a matching used unit nationwide.
By manufacturer & model
Choose your transmission
Eaton FullerManual and automated manual- Eaton Fuller 10-SpeedManual
- Eaton Fuller 13-SpeedManual
- Eaton Fuller 18-SpeedManual
Allison AutomaticAutomatic (torque converter)
Detroit DT12Automated manual (AMT)
Volvo I-ShiftAutomated manual (AMT)
Mack mDRIVEAutomated manual (AMT)
PACCAR Automated TransmissionAutomated manual (AMT)
01Manual, automated manual and automatic are different machines
Truck transmissions fall into three groups, and mixing them up is the fastest way to order the wrong unit. A manual (such as an Eaton Fuller 10-, 13- or 18-speed) uses a clutch pedal and a gear lever. An automated manual transmission (AMT) — Detroit DT12, Volvo I-Shift, Mack mDRIVE, PACCAR automated, Eaton UltraShift PLUS and Endurant — is a manual gearbox whose clutch and shifts are controlled by a computer. An automatic, such as an Allison, uses a torque converter and planetary gear sets.
AMTs and automatics need matching control modules, software and wiring, not just the right case. That's why we ask for the transmission tag and the VIN before quoting.
02Transmission families we search
Eaton Fuller manuals remain the most common Class 8 manual transmissions in the U.S. Allison automatics are widespread in vocational, refuse, bus and medium-duty trucks. Factory AMTs are now standard in many new highway tractors: Detroit DT12 in Freightliner and Western Star, I-Shift in Volvo, mDRIVE in Mack, and PACCAR's automated transmission in Peterbilt and Kenworth.
03Find and read the identification tag
Almost every heavy truck transmission carries an identification tag on the case listing its model and serial number. On an Eaton Fuller manual the model string itself describes the transmission: it encodes the series, torque capacity and number of forward speeds. Clean the tag gently and photograph it; if it's missing, the VIN and the truck's build records can often fill the gap.
- Transmission model and serial from the tag
- Truck VIN, year, make and model
- Engine model and torque rating
- Clutch type and any PTO requirements
04Matching the configuration
Two transmissions with the same name can differ in ratios (direct drive vs overdrive), input shaft and clutch size, shifter or control style, PTO openings and electronics. For AMTs, the transmission control unit, software level and harness matter as much as the gearbox. We match the configuration your truck was built with and flag any differences up front.
05Core and exchange requirements
Some transmissions, especially remanufactured units, are sold on a core exchange: you return your old transmission within a set period and in an agreed condition. Whether a core applies depends on the unit and supplier; it's stated on your quote when it does.
06Shipping a transmission
Heavy-duty transmissions ship on a skid by freight. Commercial delivery with a forklift is simplest; residential or liftgate delivery may cost extra. Check the unit before signing for it and note any damage on the delivery receipt.
FAQ
Frequently asked questions
Is an automated manual the same as an automatic?
No. An automated manual (DT12, I-Shift, mDRIVE, UltraShift, Endurant) is a manual gearbox with computer-controlled clutch and shifting. An automatic like an Allison uses a torque converter. They are not interchangeable.
Where is the tag on an Eaton Fuller transmission?
Eaton Fuller transmissions have an identification tag riveted to the case that lists the model and serial number. Our guide to identifying Eaton Fuller transmissions shows what to look for.
Can I replace a 10-speed with a 13-speed?
It can be done but usually involves different shifter, possibly driveline and clutch changes, and a check against engine torque and rear-axle ratio. Talk to your shop before changing speed count.
Do AMTs need programming after replacement?
Often, yes. The control module, software and calibration must suit the transmission and truck. We'll note what's included with the unit; programming is normally done by a dealer or qualified shop.
How do I get a transmission quote?
Call or use the form with your truck details and transmission tag. We quote a specific unit including what's included and freight.
Ready when you are
Tell us what you're running. We'll start the search.
Have your engine serial number or transmission tag and VIN handy. If you don't, we'll help you find them.