It is HTF: trafficTrendsv3 (sid)
D6742050A.sid
D6743050A.sid
I do not sure that Nuvi 2460 support this version of trends.

I can see only:
G2S: GarminAdjacencytoSSID (g2s)
JCV: PreProgrammedLaneAssistPortraitFull (jcv)
ASR: ASR (asr)
HTF: trafficTrendsv2 (db)
APT: External Point Addressing (sid) Address Point

So you need for test version 2 - D317400.db file. It is obsolete absolutely and not recommended to install and use!!! As far as I remember it must be located in internal drive only for your device.