Eaton Fuller vs PACCAR TX: AMT Transmission Comparison
Eaton Fuller Advantage
Average Score
PACCAR TX-12
Average Score
Category Breakdown
Shift Quality
PACCAR TX-12 winsThe PACCAR TX-12's shift logic is refined and well-matched to PACCAR MX engines. Shifts are smooth and well-timed. The Eaton Fuller Advantage is also smooth but the PACCAR's integrated development advantage shows in the engine-transmission calibration.
Fuel Economy
PACCAR TX-12 winsThe TX-12's co-development with PACCAR's engine team allows for optimized shift points that extract maximum fuel economy. Eaton's programming is capable but the TX-12's home-team advantage with PACCAR engines produces measurably better MPG.
Maintenance Cost
Eaton Fuller Advantage winsEaton Fuller has the largest service network in North America for transmission repair. Finding a qualified technician is easier. PACCAR TX service is growing but limited to the PACCAR dealer network.
Multi-Brand Compatibility
Eaton Fuller Advantage winsEaton transmissions are available in trucks from every major manufacturer. This universal compatibility matters for mixed fleets and makes Eaton the standard for non-PACCAR trucks. The TX-12 is exclusive to Kenworth and Peterbilt.
Warranty Coverage
PACCAR TX-12 winsPACCAR's vertically integrated warranty covers engine and transmission under one roof, simplifying claims. Eaton's warranty is comprehensive but resolving issues may involve coordination between the engine and transmission manufacturers.
Score Summary
| Category | Eaton Fuller Advantage | PACCAR TX-12 | Leader |
|---|---|---|---|
| Shift Quality | 85 | 88 | PACCAR TX-12 |
| Fuel Economy | 82 | 86 | PACCAR TX-12 |
| Maintenance Cost | 82 | 80 | Eaton Fuller Advantage |
| Multi-Brand Compatibility | 92 | 55 | Eaton Fuller Advantage |
| Warranty Coverage | 82 | 88 | PACCAR TX-12 |
| Overall Average | 85 | 79 | Eaton Fuller Advantage |
Our Verdict
The PACCAR TX-12 wins in Kenworth and Peterbilt trucks where its integrated development advantage with PACCAR MX engines produces the best shift quality and fuel economy. The single-manufacturer warranty simplifies ownership.
Eaton Fuller Advantage wins for universal compatibility and service network breadth. In non-PACCAR trucks, Eaton is the standard and often the only choice. Their service network ensures you can find transmission help anywhere.
In a Peterbilt or Kenworth: choose the TX-12. In any other truck: Eaton Fuller is the proven standard.
Frequently Asked Questions
Need Help Choosing?
Browse our in-depth reviews, use our free comparison tools, and check out our calculators to find the right products for your trucking business.
More Head-to-Head Comparisons
Published March 25, 2026