Cruiser bottom bracket is clicking and grinding My Trek Pure Deluxe 3-speed cruiser has been making a clicking noise when riding for some time. The problem is faint, and is more felt than heard. However, it's been getting worse; it now makes a grinding noise if I'm mashing a bit when going uphill. 

The noise seems to happen when the right crank arm is facing forward. Which gear I'm in makes little difference. I've eliminated saddle noise (by pedaling out of the saddle) and have replaced the chain. 

Is there anything else at all that this could be, or should I just replace the BB at this point?
Yeah, the first thought would be a loose crank arm, and if it isn't tended to immediately (if it's not too late already) the crank arm and possibly the spindle will be destroyed.

The other possibility, if this is a cartridge BB, is that the cartridge is slightly loose.  But in that case the noise is usually only present under high load.

[I'll add that tightening the crank arms is one of the half-dozen or so items that should be taken care of during the free once-over (after a few months use) that you should get from a bike shop if you buy a bike there.]