If you didnt check em bone dry and clean your not going to be able to tell. Id be really shocked if they were tight with no lash with no shims. Check those spider gear pins too to make sure they aren't starting to groove. I find I need to replace em every 3-4 gallons worth of use. I believe they exibit the same potential wear issues the new SCTE displays, instant torque brushless power will probably wear em quick. If those pins are showing wear, then those spiders aren't going to last very long regardless of shimming, especially if your using heavy diff fluid at or over 10k.