OS X V10.6 Snow Leopard :: Are Older Crash Logs Saved Someplace?

My older model MacBook Pro has been crashing quite frequently (2.2 GHz Intel Core 2 Duo runming OS X 10.6.8).I took it into the Apple store today and they said the culprit is my failing hard drive. It's not my original hard drive as I had a larger one installed some time ago. I did not have it installed at an Apple store but rather at an authorized third party store.The Genius Bar employtee today told me that if it's within a year of purchase, that third party store will most likely replace it under warranty. Unfortunately I am not currently in the city where this store is but I will call them today to see when it was that I purchased the drive. If it's been over a year, I want to tell them that these crashes did not start today but several months ago. we can go by the date of the first crashes as opposed to today's date as perhaps that will fall within the 12 month rule.However, when I look in the CrashReporter or DiagnosticReport folders in the Library and Logs folders, I'm only finding the most recent crashes. Are older crashed saved and accessable someplace else? 

Info:
MacBookPro, Mac OS X (10.6.8)