When my cherokee gets up to operating temperature i am having trouble shifting into gear especially first. I changed out the transmission fluid with mobile 1 synthetic 10w30 the other day and it didn't help. The clutch master/slave cylinder is not even a year old since last i changed it along with a new clutch. I checked the clutch fluid and it is full. I was thinking i might wrap the clutch line with heat shield to keep the clutch fluid cooler.