At first glance, a radiator seal might not look like the most important part of your heavy equipment. It’s small, inexpensive, and easy to overlook. But MESABI® rubber seals are one of a kind — and using knockoff versions can bring an operation to a halt.
Across the mining and heavy-equipment industries, more knockoff “MESABI® -like” seals have been showing up in recent years. They may look identical to the real thing, but their performance tells a very different story.
Built to Last and Tested to Prove It
At L&M Radiator, every genuine MESABI® seal is designed, tested, and verified to perform under the harshest conditions on the planet. That means years of research and development, long-term lab testing for compatibility with oils and coolants, and strict inspection before any seal leaves the factory.
“We inspect every single seal shipment that comes in,” explained Chris Domogalla, application engineering manager at L&M Radiator. “We physically inspect our seals, making sure there’s no defects. If one seal fails, the whole radiator can leak — and that’s downtime no production can afford.”
That kind of attention to detail isn’t something others replicate. Knockoff seals often fall outside of L&M’s manufacturing specifications, and many are made from lower-grade rubber compounds that harden, swell, or crumble when exposed to heat and fluids.
In testing, L&M engineers have seen seals turn brittle, “as hard as plastic” or balloon to several times their original size after limited exposure to coolant. When that happens, the result is predictable: leaks, breakdowns, and costly downtime.
“We’ve inspected knockoff seals that fall completely outside our dimensional tolerances,” said Domogalla. “Those lesser quality parts might save someone a few dollars, but they’ll cost thousands in unplanned downtime.”
The Real Cost of “Cheaper” Parts
Customers sometimes turn to knockoffs to save money — or, more often, don’t realize they’re being sold knockoffs. Radiator shops trying to cut corners may quietly install knockoff seals while charging for genuine MESABI® parts.
“Most customers have no idea,” said Ryan Daley, sales representative at L&M. “They take their radiator in for repair, and the shop installs knockoff seals thinking no one will notice. But when those seals fail, it’s the equipment owner who pays the price.”
Failures can happen within weeks. One mine site in North America called L&M furious that their “MESABI® radiator” had started leaking almost immediately — only to discover it wasn’t a genuine MESABI® product at all. “They couldn’t believe our quality had dropped so much,” Daley recalled. “We had to explain it was a knockoff, then help them replace it with the real thing.”
Even one single faulty seal can shut down a multi-million-dollar piece of equipment. What looks like a small saving on parts can turn into hundreds of thousands of dollars in lost productivity.
Why Material Science Matters
To the naked eye, rubber is rubber. But just as there are many alloys of steel, there are countless formulations of rubber compounds — and those details make all the difference.
“Rubber may look the same, but it isn’t,” said Chuck Cedar, R&D engineer at L&M. “We spend years fine-tuning our formulations with suppliers, so our seals maintain elasticity, resist oxidation, and perform in any environment from Arctic cold to desert heat.”
By contrast, most copycat manufacturers test their materials for only a few days or weeks, if at all. MESABI® seals are tested over long periods and under varying conditions to ensure they last for years — often the lifetime of the machine. In one Minnesota mine, for example, operators have run the same MESABI® radiator for decades without a single seal replacement.
Spotting the Fakes
Fortunately, genuine MESABI® seals are easy to identify. Each carries the MESABI® name and registered trademark, along with a part number stamped directly into the rubber. If that identification isn’t visible, it’s not a genuine MESABI®.
Customers should also be wary of misleading language. Products advertised as “MESABI®-like,” “MESABI®-style,” or “rubber-grommeted tube radiators” are not made by L&M Radiator. And any vendor referring to seals as “grommets” — a term L&M deliberately avoids — is likely selling a low-quality imitation.
To be safe, the company recommends ordering directly from L&M Radiator or an authorized distributor, and specifying genuine MESABI® whenever a radiator is serviced or repaired.
“If you’re unsure,” said Daley, “contact us or your local MESABI® representative. We’ll help verify what you’ve got.” Click here to find the L&M service representative for your region.
Proven Performance Worth Protecting
The MESABI® reputation was built over generations. Each component — from the tubes to the seals — is engineered to deliver unmatched durability and uptime. Knockoff seals undermine that reliability and risk damaging the trust customers have placed in the MESABI® name.
“The word MESABI® has become synonymous with an entire category,” said Cedar. “People try to use the word to describe a style of radiator, but there’s only one original. There’s only one MESABI®, and it’s from L&M Radiator.”
When it comes to protecting critical equipment, imitation is not flattery — it’s a liability. Genuine MESABI® seals aren’t just rubber rings; they’re the result of decades of engineering, testing, and performance data.
So, before your next rebuild or repair, take a closer look. If it doesn’t say MESABI®, it’s not MESABI® — and that’s a risk you can’t afford to take.
There’s Nothing Like a Genuine MESABI®
For more stories similar to this one, visit the blog on www.Mesabi.com.