Can Pellets Be Too Old

Depending on how/where they were stored, they may get moldy/mildewed but otherwise they should be ok. What smoker are you using? What temp? Have you tried other pellets?

Good question; I don't recall seeing it asked before.

If they've been stored in the original bags and still airtight, I'd think they'd be fine. Given your descriptions, perhaps age does affect quality. Give Cookshack a call and get their advice. The large amount of ash & dirty flavor doesn't seem right for oak pellets.

I was kinda wondering about that too. I've got a half ton stored in my shop setting on a pallet on a concrete floor. The roof does drip a bit, but not on the pellets. The humidity in the shop is about the same as it is outside, as the electric is not on. I'd imagine, like any wood product, the shrink and expand a little with humidity conditions, taking in the surrounding aroma. If it's musty, well, who knows. Did they smell like wood or dirt? Mine still smell like nice pecan, but they are only a year old. I did have several bags that were kept for four years, but were kept inside out of the humidity, they still smelled good and there was no noticeable ash or dust. All mine are BBQ delight, but not sure that would matter.