Size Range
A4VSO runs from size 28 to 500 and A10VO from 16 to 140. If the machine needs more than around 140 the choice has already been made for you.
Typical Machines
A4VSO is an industrial pump: presses, test benches, steel plant and marine power packs running long hours at high pressure. A10VO is a compact mobile pump: mini excavators, skid steers, telehandlers and truck mounted equipment.
Duty Pattern
A4VSO tends to run continuously at a steady setting. A10VO cycles constantly as the operator works the machine, which loads the control far more often.
What Wears First
On both frames it is the shoe faces and the block face. On A10VO the control also sees far more cycles, so control wear is a more common finding at strip down.
Cost of Repair
A10VO parts are less expensive and more widely available, which makes a single part repair worthwhile more often. On A4VSO, particularly the larger sizes, a matched rotary group is usually the better decision because the labour and downtime outweigh the part price difference.
Availability
We hold both. The A10VO sizes 28 to 100 and the A4VSO sizes 71 to 180 move fastest and are normally on the shelf.
Which To Choose For a Replacement
This is rarely a free choice. You replace what is in the machine. The comparison matters when you are deciding how deep to go on a repair, and there the answer is that A4VSO usually justifies a full matched set while A10VO more often justifies a targeted part replacement.
