Could be. I just know I had seeps after a timing belt change. I didn't replace the hoses at 270k due to a water pump leak. So when I put the new hoses in my clamps didn't leak anymore.I postulate that the original (and, presumably, the OEM replacements) are designed for a specific hose diameter. If a non-conforming, smaller-diameter hose is used, even if it's a "good quality" hose, the originals may not provide enough clamping force.