CM classified digital edition - 15 October
Used DAF XF: 10 common issues
The DAF XF is, as we have said, a very sturdy and well-built tractor unit, so there have been very few major component failures reported. Nothing mechanical is completely faultless, however, so here’s a list of things operators have told us may crop up:
1. Hub seals
Larger fleets report a noticeably high number of instances where hub seals need replacing.
2. Brake discs
Replacing brake discs often requires the hub to be sent away to a specialist to have the seized mounting bolts drilled out. DAF sells a complete new disc and hub assembly on an exchange basis.
3. Rear axle modulator valve
Wiring for the rear axle modulator valve is prone to breaking down within its protective sleeving. Check for temporary repairs that have been left to become permanent.
4. NOx sensors
NOx sensors often need replacing. Check to see if this has already been done.
5. Heat shields
Reports of heat shields corroding. Check for evidence this is beginning to happen.
6. Gauge clusters
Some reports of gauge clusters in the dashboard cracking for no apparent reason.
7. Wheel wings
Examples of the wings behind the front wheels cracking, especially across the joints and at the bottom where they meet the spray-suppression flaps.
In theory, drivers should use the air dump before getting in and out of the seats, but many don’t. This can result in the outside edge of the seat squab giving way, especially if the driver is of a larger build. Check before buying, then educate to avoid recurrence.
9. APU valves
APU valves on the air system are prone to corrosion, probably due to their low-slung position. Avoid by paying particular attention to this area when washing the vehicle.
10. Air pressure
Vehicles prone to losing air pressure very quickly when parked up overnight. The problem is usually the exhaust brake solenoid, which is positioned alongside the engine and therefore prone to repeated expansion due to heat followed by contraction on cooling leading to a gap.