How Automotive Supplier Cut its Return Transport Costs by 125%?
Return Transport Cost importancy?! The road from Sofia to northern Spain stretches across almost the entire Southern European continent. Thousands of kilometres of highways, mountain passes and border crossings separate the production halls of a Bulgarian automotive supplier from the assembly plants of its customer in Spain.
Every week, trucks leave Bulgaria loaded with precision-engineered aluminium components – parts destined for electric vehicle platforms, chassis systems and structural assemblies. They travel west full.
They return empty.
Or at least, that used to be the case.
When I arrive at the company’s modern production facility on the outskirts of Sofia, the first thing that stands out is movement. Forklifts glide silently between loading bays. Aluminium profiles, freshly machined, move along automated conveyors toward packaging stations. The atmosphere is calm but deliberate – the unmistakable rhythm of Tier-1 automotive supply.
A Logistics Problem Hidden in Plain Sight
For years, the company relied on traditional steel Gitterboxes to transport its components to Spain. The containers were durable, familiar to customers, and fully compatible with existing automotive logistics systems.
“They worked perfectly during transport,” the project manager, Ivaylo, explains as we walk past stacks of finished components awaiting dispatch. “The problem was not going full. The problem was coming back.”
Each shipment required the empty containers to return to Bulgaria for reuse. Because Gitterboxes are rigid and bulky, they occupy nearly the same volume whether loaded or empty.
“You pay almost twice,” the plan manager, Victor, later tells me in his office overlooking the production floor. “Once to send product. And again to send back air.”
Across such long distances, those empty kilometres were expensive. Fuel prices fluctuated. Driver shortages increased rates. Sustainability targets added pressure to reduce unnecessary transport.
At one point, logistics costs began eroding margins on otherwise successful contracts.
“We realised we were optimising production continuously,” the plant manager Victor says. “Automation, energy, materials. But logistics – that was almost untouched.”
The First Conversation with ZAMKO
The turning point came during discussions with industrial packaging specialist ZAMKO.
According to the project manager Ivaylo, the initial proposal sounded almost too simple.
“They said: what if you could save more than 50% on your transport costs of returning logistic packaging?”
He laughs.
“In automotive, when somebody says that, you immediately start looking for the catch.”
The suggestion was to replace the Gitterbox pool with collapsible mesh wire pallet cages – designed to remain fully interstackable with the current Gitterboxes.
The key advantage lay in reverse logistics.
Folded cages occupy dramatically less volume.
“We could load 2.25 times more empties into one truck.” Says Ivaylo.
Convincing the Customer
Changing packaging in automotive supply chains is rarely simple. Every container interacts with multiple stakeholders: assembly plants, warehouse operators, transport providers and quality engineers.
“The biggest challenge wasn’t internal,” the project manager explains. “It was convincing our customer.”
Spanish receiving plants were accustomed to standard Gitterboxes. Changing equipment risked operational disruption – something OEM supply chains avoid at almost any cost.
Here, compatibility became decisive.
“The cages stacked perfectly with existing Gitterboxes,” he says. “During transition, both systems could circulate together.”
No warehouse layouts needed redesigning. Forklift handling remained identical. Loading heights stayed the same.
“From their perspective,” Ivaylo adds, “nothing changed operationally.”
ZAMKO engineers worked closely with both sides to test stacking stability, handling safety and loading patterns.
“They didn’t come only with a product,” the plant manager Victor notes. “They came with calculations.”
Detailed transport simulations showed potential savings across a full year of return logistics between Bulgaria and Spain.
“That’s when the discussion changed,” Victor says.
The Economics That Made the Decision
In the conference room, spreadsheets appear on a screen.
Transport costs, kilometres driven, CO₂ reduction estimates.
“The numbers convinced everyone,” the project manager says.
Return transport, return trucks previously carrying empty Gitterboxes often reached volume limits long before weight limits. With foldable mesh cages, utilisation improved dramatically.
Instead of sending multiple trucks west-to-east every week, fewer vehicles were required.
“The saving is not ten percent,” Ivaylo explains. “It is structural.”
Fuel consumption decreased. Fewer drivers were required. Administrative handling dropped.
Even unexpected benefits appeared.
“When fewer trucks arrive,” he says, “yard congestion decreases. Scheduling becomes easier.”
Victor, the plant manager, leans forward.
“In automotive supply, reliability is more important than price. But when reliability stays identical and price improves significantly – then the decision becomes obvious.”
No Disruption Allowed
Perhaps the most remarkable part of the transition is how little actually changed inside the factory.
On the packaging line, operators continue loading components exactly as before.
Forklifts approach cages from the same angle. Stack heights remain standardised.
“We promised our teams there would be no operational complications,” the project manager says.
That promise mattered.
Production facilities running contracts for major European car manufacturers cannot afford experimental logistics solutions that slow throughput.
“The cages entered circulation gradually,” he explains. “Mixed with Gitterboxes.”
Because both systems interstacked safely, the transition happened invisibly.
“There was no big switch-off moment,” he says. “One week you noticed more cages than gitterboxes.”
Sustainability as a Bonus
Although cost savings drove the project, environmental gains quickly followed.
Fewer return trucks meant lower emissions.
For a company increasingly focused on lightweight materials and electrification projects, the alignment mattered.
“We are already investing heavily in sustainable production,” the plant manager says. “Energy efficiency, renewable power agreements, lightweight materials.”
Reducing unnecessary transport kilometres supported the same philosophy.
“You cannot talk about sustainability only inside the factory,” he adds. “Logistics is part of the footprint.”
Lessons Learned
As trucks depart the loading bays behind us, each trailer precisely filled, the project manager reflects on what surprised him most.
“How simple the solution was,” Ivaylo says.
- No new warehouse investments.
- No retraining programmes.
- No redesign of transport equipment.
“Sometimes innovation is not robotics or software,” he says. “Sometimes it is just asking: why are we transporting empty space?”
ZAMKO’s role, he emphasises, was not only supplying equipment but guiding the calculation process.
“They understood both packaging and logistics economics.”
For Victor, the plant manager, the lesson is even broader.
“In automotive, people resist change because mistakes are expensive,” he says. “But if you can change without risk – that is powerful.”
Outside, another truck begins its long journey west toward Spain, loaded with components destined for the next generation of European vehicles.
And when it returns to Bulgaria, it will carry far less air than before.
