In Brief
Axle service covers BPW, SAF, ROR and Jost systems: bearing replacement, hub repair, air suspension, and brake integration. Bearing replacement on one hub: 2–4 hours. Complete axle service: 1 working day. Quotation on request.
A trailer axle carries the full payload weight and transmits braking forces. A 44-tonne loaded silo trailer puts several tonnes through each axle. At these load levels, bearings, hubs and suspension wear faster than on passenger vehicles – and the consequences of failure are proportionately more serious.
PHS Magnum services axle systems on all trailer types, with particular expertise in the axles used in silo trailers and cement tankers (BPW, SAF).
Axle service scope
Wheel bearings – replacement of tapered or fully integrated hub bearings. Diagnosis: thermal camera at the wheels after a run, bearing play measurement. Under normal use bearings last 800,000–1,200,000 km.
Hubs and half-hubs – regeneration or replacement if the thread is damaged or the hub is cracked. Assessment after disassembly.
Seals – oil seal replacement on leaks. Typically done at every bearing replacement.
Drum brakes – during axle service we inspect and service the brakes (linings, drums, cylinders). Brake repair →
Air suspension – air bag replacement, levelling valves, bellows replacement. A worn air bag means the trailer cannot maintain correct ride height and contacts the frame. One bag replacement: 3–5 hours.
Suspension arms and swing arms – for post-collision deformation or material fatigue. Running gear geometry corrected after repair.
When to service the axle
| Component | Service interval |
|---|---|
| Bearings | every 300,000–500,000 km or on symptoms |
| Seals | at every bearing replacement |
| Brake linings | every 80,000–120,000 km or at thickness < 4 mm |
| Air bags | on leakage or deformation |
For intensive operation (heavy loads, urban routes with many stops): reduce intervals by 20–30%.
Axle service for silo trailers — special considerations
Silo trailers present specific axle service challenges that differ from standard flatbed or curtainsider trailers:
Weight distribution: A fully loaded 65 m³ silo trailer carrying PE/PP granulate (bulk density ~0.5 t/m³) weighs around 32 tonnes. A cement load can approach 40+ tonnes. Axles are at or near maximum rated load for extended periods — this accelerates bearing wear significantly compared to lighter trailers.
Corrosion in the pneumatic discharge zone: The underside of a silo trailer is exposed to the same alkaline environment as the tank interior (cement, lime dust). Axle components in the rear area near the discharge outlet experience accelerated corrosion on the outer surfaces. Routine inspection and corrosion treatment during service is essential.
TDT inspection link: As noted above, the TDT inspector checks the running gear condition. Axle issues found during TDT pre-inspection can be addressed in the same service visit — avoiding a separate trip.
BPW vs. SAF — what’s different in service
Both BPW and SAF are common on Spitzer and Feldbinder trailers, but the service procedure differs:
| Feature | BPW EBC/ECG | SAF INTEGRAL |
|---|---|---|
| Bearing type | Tapered roller (cup and cone) | Integrated hub bearing unit |
| Replacement approach | Individual bearing elements | Full hub unit replacement |
| Service interval | Every 300,000 km or by wear | By wear or hub unit failure |
| Brake drum | Separate drum on hub | Integrated drum in some versions |
| Air suspension brand | BPW airLIFT | SAF INTEGRAL suspension |
Knowing which axle type is fitted is important before ordering parts — BPW and SAF hubs are not interchangeable.
What to check when buying a used silo trailer
When evaluating a used Spitzer, Feldbinder or Kassbohrer trailer for purchase, the axle and running gear condition is often overlooked in favour of the tank condition. A checklist for quick axle evaluation:
- Thermal camera after 30 km run — hot hubs indicate bearing problems.
- Wheel wobble check — grab the top and bottom of each tyre and rock it. Detectable play indicates worn bearings or king pins.
- Tyre wear pattern — stepped or angled wear indicates axle misalignment or suspension arm issues.
- Hub oil seals — grease or oil streaks on the drum indicate failed seals.
- Air suspension bags — look for cracks, deformation, or signs of rubbing on the frame.
PHS Magnum offers pre-purchase inspection for used silo trailers — combining axle check with tank condition, pneumatic system test and TDT status verification. Contact us to arrange: +48 602 716 551.
Contact – axle service
Tel: +48 602 716 551 Email: biuro@magnumchorula.pl ul. Kościelna 9, 47-316 Chorula · Mon–Fri 06:00–20:00, Sat 07:00–15:00
Related: Brake repair · EBS diagnostics · Silo trailer service · Mobile service A4
