My 2010 2500 with 6 speed manual tranny makes an odd clatter at about 1800 rpms. It is most noticible in 5th gear and it only does it between about 1700 and 1900 rpm. The truck has 50,000 miles on it and it has been doing it for a while. Its the same diesel clatter, it just gets louder and faster in that rpm range. Wondering if it is something I should have the dealer look at or just normal.

 

I would take it in. There's been a few guys had their dual mass flywheel/flexplate come apart. If I remember right they complained of some odd noises before it finally let go. Might be nothing but, I'd let the dealer check it out just to be sure.

jeff.