Product Manufacturer: Rodmounts
I have a set of Sumo rod carriers from Rodmounts that use a suction cup to attach to my vehicle. They are probably 6 or 7 years old by now and the suction cups don't grip as well as they used to. I stumbled across a blog post from ginkandgasoline about upgraded suction cups being available so I dropped an email to Rodmounts customer service.

5 days later I have a new set of suction cups in my mailbox free of charge and my Sumo carrier is working like new. My kind of customer service.

http://www.rodmounts.com/