User Review: Eureka! Timberline 2

Actually this is a question. We've owned our Timberline for six years and we are very pleased with it. We are about to embark on a month-long backpacking excursion and are wondering if we should reinforce its waterproofing with a 13% silicon heavy duty water repellent. The tent has never leaked but with its age and the duration of our trip we were trying to figure out if it would be a good idea. If you can give any input on this it would be greatly appreciated. Thanks!