Truck Transmission
PACCAR TX-8 (medium-duty AMT)
AMT • 8-speed • PACCAR
Production 2022–present
Class 6-7
660 lb-ft
In production
Type
AMT
Gears
8
Torque capacity
660 lb-ft
Production
2022–present
About the PACCAR TX-8 (medium-duty AMT)
The PACCAR TX-8 is PACCAR's medium-duty AMT for Class 6-7 trucks — gives Kenworth T270/T370 and Peterbilt 220/337/348 buyers an alternative to Allison automatic. 8 forward gears, integrated with PACCAR PX-7 and PX-9 engines. Launched 2022 as part of PACCAR's medium-duty modernization.
Overview
The PACCAR TX-8 is PACCAR's medium-duty AMT for Class 6-7 trucks — gives Kenworth T270/T370 and Peterbilt 220/337/348 buyers an alternative to Allison automatic. 8 forward gears, integrated with PACCAR PX-7 and PX-9 engines. Launched 2022 as part of PACCAR's medium-duty modernization.
Specifications
- Manufacturer
- PACCAR
- Type
- AMT
- Gear count
- 8
- Torque capacity
- 660 lb-ft
- Truck classes
- Class 6-7
- Applications
- Medium-duty Kenworth + Peterbilt
- Production years
- 2022–present
Design and engineering
8-speed AMT, integrated clutch, PACCAR electronic control.
Generations and updates
TX-8
2022–present
Launch in medium-duty Kenworth + Peterbilt.
Reliability and longevity
Too new for long-term data.
Common problems
Brand-new — unknown.
Driver experience
Smooth AMT operation in medium-duty.
Pros and cons
✓ Pros
- • PACCAR-integrated medium-duty AMT
- • Alternative to Allison automatic
- • Optimized for PACCAR engines
⚠ Cons
- • Brand-new — unproven
- • Competes against the proven Allison 2500/3000 in same segment
Trucks using this transmission
Engines paired with this transmission
Related
Frequently Asked Questions
What is the PACCAR TX-8 (medium-duty AMT)?
The PACCAR TX-8 is PACCAR's medium-duty AMT for Class 6-7 trucks — gives Kenworth T270/T370 and Peterbilt 220/337/348 buyers an alternative to Allison automatic. 8 forward gears, integrated with PACCAR PX-7 and PX-9 engines. Launched 2022 as part of PACCAR's medium-duty modernization.
What trucks use the PACCAR TX-8 (medium-duty AMT)?
The PACCAR TX-8 (medium-duty AMT) is used in 5 truck models including Kenworth T270, Kenworth T370, Peterbilt 220 (cabover), Peterbilt 337, Peterbilt 348. It's typically paired with Medium-duty Kenworth + Peterbilt applications.
Is the PACCAR TX-8 (medium-duty AMT) reliable?
Too new for long-term data.
What's the difference between an AMT and a manual transmission?
Automated Manual Transmission (AMT) uses the same gearset as a manual but adds computer-controlled clutch and shifter — no clutch pedal, no manual shifting. Modern AMTs like Eaton Endurant, Detroit DT12, and Volvo I-Shift offer smooth shift quality and predictive shifting via GPS. Manual transmissions (Eaton Fuller 10/13/18-speed) require driver-controlled clutch and shifting — more driver effort but maximum control and proven reliability. Automatic transmissions (Allison) use a torque converter and clutch packs — smoothest operation but heavier and less fuel-efficient than AMTs for highway use.
How long does a PACCAR TX-8 (medium-duty AMT) last?
Commercial truck transmissions typically last 500,000 to 1,500,000 miles depending on maintenance, application, and driver skill. Manual transmissions (Eaton Fuller) routinely cross 1.5M+ miles. AMTs (Endurant, DT12, I-Shift) typically last 700K-1.2M miles before major service. Automatics (Allison) often outlast the truck itself in vocational applications. Maintenance discipline matters most — clean fluid + filter at recommended intervals extends life dramatically.
Does the PACCAR TX-8 (medium-duty AMT) affect truck resale value?
Transmission choice significantly affects truck resale. Cummins-paired AMTs (Endurant) and manual 18-speed Eaton Fullers command premium resale in owner-operator markets. Allison transmissions hold premium in vocational markets.