In-house vs. outsourced hydraulic power units: what the “cheaper to build it ourselves” math actually misses

Every few years, someone on an equipment manufacturer's team runs the numbers and concludes that building hydraulic power units in-house would be cheaper than buying them from a supplier like us. Sometimes they're right, for their volume, their labor market, and their engineering bandwidth at that moment. More often, the math they ran only priced one thing: the unit itself.

I've watched this comparison happen from both sides, as a supplier and as someone who talks to manufacturers running this exact analysis. Here's what the spreadsheet usually leaves out.

Labor cost today isn't labor cost in three years

The in-house cost model almost always uses current shop labor rates and current headcount availability. It rarely stress-tests what happens when that assembler leaves, when overtime gets expensive during a demand spike, or when the person who understood the hydraulic assembly process the best moves to a different role. A supplier's cost is fixed and quoted. In-house labor cost is a forecast, and forecasts age badly in a tight labor market.

Rework and engineering load don't show up on the unit cost line

When a hydraulic assembly built in-house doesn't perform to spec, the cost of diagnosing and fixing it comes out of engineering time that was budgeted for the next product, not out of a “hydraulics” line item. That cost is real, it's just invisible in the comparison, because it gets absorbed into general engineering overhead instead of counted against the decision that caused it.

“Cheaper” assumes one spec fits your whole product line

This is where the in-house argument and the Assumption Trap intersect directly. Building in-house only stays cheaper than outsourcing if you can standardize on a small number of hydraulic specs across your equipment range. The moment a large customer needs something outside that standard, you're either quoting a custom in-house build (which erases the cost advantage) or turning down the deal. We've seen both.

What you're actually buying from a supplier isn't just a part

When you outsource the power unit, you're not just buying a component, you're buying someone else's warranty, someone else's lead time discipline, and someone else's field service relationship. At Hydrolec, every unit comes with guarantees and support built in. When you build in-house, your own team owns 100% of that risk, on top of the parts and labor.

“I'm not going to tell you outsourcing is always right, that would be exactly the kind of one-size-fits-all thinking I'm arguing against.”

This isn't an argument for outsourcing everything

For some manufacturers, at some volumes, in-house genuinely is the better call. What I am arguing is that the decision deserves a total-cost analysis, not a unit-cost comparison, and that analysis should get revisited on a real cadence, not run once and left unchallenged for a decade.

If it's been a while since your team last ran this comparison honestly, factoring in today's labor market, today's rework rate, and today's engineering load, that's a conversation worth having. We're glad to be the ones you compare against.