Went for a bit of a drive before. Drove down my court and stopped at the bottom as usual. But this time, as I was coming to a stop, the gearbox seemed to make a quiet grinding sound. The revs also seemed to dip fairly low also (aprox. 350-400ish rpm). The sound was around the front of the gearbox, so my guess would be the torque converter. It drove normally afterwards.
Is this something I should be concerned about? and if it is a sign of something dying, how long will it last?

Cheers

anyone?

Have you checked to make sure theres enough fluid in it to stop it aerating?