Description
The ATRO MS99-63794 is a polyurethane shift-lever isolator repair kit for Eaton Fuller heavy-duty manual transmissions. The kit replaces the rubber-bonded shifter isolator that decouples the gear lever from the shift cover, restoring crisp gear engagement and eliminating the “floppy shifter” symptom common on high-mileage Fullers. Direct replacement for Fuller S1794 and Automann M23319.
Signs You Need a New Shift Lever Isolator
- Excessive sloppiness or play in the gear shift lever
- Difficulty finding gears or hard shifting
- Lever leans or tilts when in gear
- Visible cracking, deformation, or oil contamination of the existing isolator
- Vibration felt through the gear lever at idle or cruise
Specifications
| Manufacturer | ATRO |
|---|---|
| Part Number | MS99-63794 |
| Part Type | Shift Lever Isolator Kit |
| Material | Polyurethane |
| Transmission Compatibility | Eaton Fuller HD manual transmissions calling for S1794 isolator |
Kit Includes
- Shifter Isolator Bushing — (qty 1)
- Step Bushings — (qty 2)
- Shoulder Bolt — (qty 1)
- Lock Nut — (qty 1)
- Upper Adapter — (qty 1)
- Lower Adapter — (qty 1)
Cross References
This kit replaces or is equivalent to the following part numbers:
- Eaton Fuller: S1794
- Automann: M23319
- ATRO: MS99-63794
Applications
This isolator kit fits Eaton Fuller heavy-duty manual transmissions that originally use the S1794 shifter isolator, including 9-, 10-, 13-, and 18-speed Fuller Roadranger transmissions installed in:
- Kenworth W900, T800, T660, T680 with Fuller manual transmissions
- Peterbilt 379, 389, 386, 567, 579 with Fuller manual transmissions
- Freightliner Cascadia, Columbia, Century, FLD with Fuller manual transmissions
- International, Mack, and Volvo trucks specifying Fuller S1794 isolator
The ATRO removal tool PT99-63399 simplifies pulling the old isolator from the shift cover. Inspect the shift cover bore and the shifter ball for wear before reassembly.
