Overview
The ZF 5838.300.013 PISTON is a critical hydraulic actuation component engineered for the WG100, WG130, and WG131 powershift transmission series. This OEM genuine part converts hydraulic pressure into mechanical force to engage clutch packs and modulate gear shifts within the transmission valve body. As a precision-machined component, the SKU 5838.300.013 ensures consistent oil flow control and pressure regulation, directly influencing shift quality and torque transfer efficiency. When paired with a properly functioning 5838022003: REAR AXLE, this piston maintains driveline synchronization under heavy load conditions.
Symptoms of Failure
- Delayed or harsh gear engagement: A worn 5838.300.013 piston allows hydraulic pressure bleed, causing hesitation when shifting from neutral to drive or reverse.
- Intermittent transmission slipping: As the piston seal degrades, the clutch pack fails to lock fully, resulting in RPM flare under acceleration without corresponding vehicle speed increase.
- Hydraulic oil contamination: Cracks or scoring on the piston surface introduce metallic debris into the transmission fluid, visible as dark particles on the dipstick.
- Erratic shift patterns: The piston’s inability to maintain consistent pressure causes unpredictable upshifts or downshifts, particularly in WG130 models operating at high torque.
Technical Specifications
| Parameter | Specification |
|---|---|
| Part Number | 5838.300.013 |
| Material | Hardened alloy steel with nitrided surface |
| Outer Diameter | 68.5 mm |
| Inner Diameter | 42.0 mm |
| Height | 32.8 mm |
| Weight | 0.185 kg |
| OEM Reference | ZF 5838.300.013 |
| Seal Type | PTFE lip seal (integrated) |
Compatibility
This piston is specifically designed for ZF WG100, WG130, and WG131 transmissions used in agricultural tractors, construction loaders, and industrial material handlers. It is a direct replacement for the hydraulic actuation circuit in the clutch housing assembly. While not compatible with WG180 or WG200 series, the 5838.300.013 works in conjunction with the 5838109001: DIFFERENTIAL to distribute power evenly across drive axles. For complete rebuilds, always inspect the 0750117075: TAPER ROLLER BEARING and 5838300128: DIFFERENTIAL HOUSING for wear during piston replacement.
Related Components
| Part Number | Name | Function |
|---|---|---|
| 0631329086 | SPRING PIN | Secures piston alignment in bore |
| 5838300129 | THRUST WASHER | Reduces axial friction on piston |
| 5838300130 | THRUST WASHER | Secondary axial load distribution |
| 5838300131 | AXLE BEVEL GEAR | Transfers torque to differential |
| 5838300132 | COMPENS. STUB AXLE | Compensates for axle misalignment |
| 5838300133 | COMPENS. STUB AXLE | Alternate compensation axle variant |
| 5838022003 | REAR AXLE | Final drive output assembly |
| 5838109001 | DIFFERENTIAL | Distributes torque between wheels |
| 0750117075 | TAPER ROLLER BEARING | Supports rotating shaft loads |
| 5838300128 | DIFFERENTIAL HOUSING | Encloses differential gear set |
