Early cycle recovery meets new raw material cost pressures
- Atmus is mainly a replacement-filter business, with aftermarket sales making up about 86% of 2025 net sales.
- The first-fit market showed early signs of a cyclical recovery in Q2 2026, pushing Power Solutions sales up 7%.
- The Industrial Solutions segment added $42 million in Q2 2026 sales but saw its margin compress to 18.9%.
- Raw material inflation and joint venture weakness are pressuring profit margins for the second half of 2026.
- Customer concentration is high, with Cummins, PACCAR, and Traton making up 18.8%, 16.3%, and 11.5% of 2025 net sales.
A first-fit recovery faces new cost headwinds
Atmus has a simple core idea. Engines and heavy machines need filters, and those filters must be replaced over time. That gives the company a large recurring base. In 2025, aftermarket sales were about 86% of net sales, while first-fit sales to original equipment makers were about 14%.
The bull case gained momentum in Q2 2026. Total sales hit a record $528 million. The core Power Solutions segment grew 7%, driven by better pricing and an early cyclical recovery in the first-fit market. The new Industrial Solutions segment also added $42 million in revenue, continuing the push into non-engine markets.
The bear case has shifted from volume weakness to cost pressures. The global aftermarket remains flat. More importantly, management warned that the Middle East conflict is driving inflation for raw materials like plastics and chemicals. This issue is expected to drag on profit margins in the second half of 2026.
This leaves the stock story balanced. The volume tailwind is taking hold earlier than expected, but the margin upside is capped by supply chain costs and temporary integration expenses. Atmus needs to show it can pass on these new costs while keeping its recovery intact.
Replacement filters pay the bills
Atmus sells filters under the Fleetguard brand for on-highway commercial vehicles and off-highway equipment used in agriculture, construction, mining, and power generation. Filters protect engines and equipment by keeping dirt and other harmful material out of the system.
The best part of the model is repeat demand. After a truck, tractor, generator, or mining machine is in service, filters wear out and must be replaced. That is the aftermarket business, and it made up about 86% of 2025 net sales.
The weaker part is the first-fit business. These are filters sold to original equipment manufacturers for new machines. This piece was about 14% of 2025 net sales and is more tied to new truck and equipment production.
The model also depends on a few very large customers. In 2025, Cummins accounted for 18.8% of net sales, PACCAR for 16.3%, and Traton Group for 11.5%. That concentration can help volume and access, but it also gives those customers power.
Filters for engines, machines, and buildings
Fleetguard replacement filters
These are replacement parts for vehicles and equipment already in use. This aftermarket base is the main reason Atmus has recurring revenue.
First-fit engine filtration
Atmus sells filters to original equipment manufacturers that install them in new vehicles and machines. This business is showing early signs of a cyclical recovery.
Off-highway filtration
The company serves agriculture, construction, mining, and power generation equipment. These markets can be cyclical, but the installed base supports future replacement demand.
Commercial and industrial HVAC air filters
Koch Filter gives Atmus a broader air filtration portfolio. It adds exposure to commercial and industrial buildings.
Data center and power generation air filtration
Industrial Solutions targets higher-growth settings such as data centers and power generation environments. The segment is scaling up but faced temporary margin pressure in Q2 2026.
Two segments, one still dominates
Segment mix uses Q2 2026 net sales: $486 million from Power Solutions and $42 million from Industrial Solutions. Customer concentration remains important because Cummins, PACCAR, and Traton together made up a large share of 2025 net sales.
What could break the story
Raw material inflation hurts margins
High impact · High oddsThe Middle East conflict is increasing the cost of chemicals and plastics. Management expects these inflationary pressures to persist in the second half of 2026. If the company cannot raise prices enough, profit margins will shrink.
Aftermarket demand stays flat
High impact · Medium oddsThe aftermarket is the recurring core of Atmus. Global aftermarket growth remains flat with weakness in Europe, the Middle East, and the Asia-Pacific region. If replacement demand weakens further, the company loses its main defense against the equipment cycle.
Koch Filter margin compression
Medium impact · Medium oddsIndustrial Solutions contributed $42 million of sales in Q2 2026, but its adjusted EBITDA margin fell sequentially to 18.9%. While management blamed one-off transition costs, any prolonged inefficiency could ruin the margin upside of this new segment.
Large customers squeeze Atmus
High impact · Medium oddsAtmus depends on a small group of major customers. Cummins, PACCAR, and Traton accounted for 18.8%, 16.3%, and 11.5% of 2025 net sales. A lost program, lower production plan, or tougher pricing from any one of them could matter.
In one breath
What does Atmus Filtration Technologies do?
Atmus makes filtration products, mainly under the Fleetguard brand. Its filters are used in commercial vehicles, heavy equipment, power generation systems, and now industrial air filtration markets.
Why does the aftermarket matter so much for Atmus?
Aftermarket filters are replacement parts for equipment already in use. That creates repeat demand, which is steadier than selling parts only for new trucks or machines.
What changed after the Koch Filter acquisition?
Koch Filter created the new Industrial Solutions segment. In Q2 2026, it added $42 million of sales, giving Atmus a new growth path outside its core engine filtration business.
What is the main risk for ATMU stock?
The main risks are flat aftermarket demand and rising raw material costs. Even though the first-fit market is recovering, higher costs for plastics and chemicals could hurt profit margins.
