I don't know how long Gerbing has been making heated gear for HD, the booklet that came with my gear has no date in it but it lists Gerbing and the Gerbing Warranty Dept in Tumwater, WA as the location to return for warranty claims (or your HD dealer, which I have done).
The warrant says:
"When you purchase this Harley Davidson heated garment within the United States and Europe, the electrical components of the garment are warrantied to be free from defects in materials and workmanship for the life of the garment. All other components of the garment are warrantied to be free from factory defects in materials and workmanship for a period of one (1) year from the date of the first retail purchase."
They fixed my 2 year old right glove wiring and the dealer told me to bring in my liner to get the sleeve to glove wiring fixed...free.
See Gateway HD online, they also state "lifetime warranty" for liner and gloves.
http://gatewayharley.blog.com/tag/heated-gear/T