Preparation for Test

1. Depressurize rear axle hydraulic system by slowly opening bleed screw (57a). 2. Connect test gauge (038) with hose (038e) to distribution fitting (57) in place of bleed screw (57a). 3. Check oil level in oil reservoir, correct if necessary. 4. Connect HHT (refer to section 0). Monitor oil level during testing, air must not be allowed to enter the system through the hydraulic pump.

		Test scope	Test connection	Test condition	Nominal value	Possible cause/Remedy
1.0		Leveling valve Opening pressure Relief valve Overflow valve	250 bar at rear axle distribution fitting	Engine: at Idle HHT activation: raise HHT activation: lower (5 min)	180 - 190 bar 33-36 bar after 5 min.	Delivery pressure > 190 bar Replace leveling valve. Delivery pressure < 180 bar Hydraulic pump test 32. Replace leveling valve.