for me. On occasions it appears they do sweat a little. Regardless my OCD makes me chexk all fluids before any and all road trips. Thanks again for sharing the article. I actually had the original Z1 oil cooler hoses and they sweated enough oil that I thought I had a leak. I just replaced these last week with new Z1 silicon hoses that have a liner to prevent the "sweating" of oil. I should mention that Z1 gave me great service as the hoses have a warranty that I was not aware of. Cheers