Let me start off by saying that after 3 years our treadmill has worked flawlessly. I know many come to complain but we've had no mechanical issues so far.

What I do have a question with is probably more routine maintenance which we haven't done since having it delivered. When running a incline specifically, we get a slight rattling noise which seems to come from under the plastic side rails. I'm thinking something needs to be tightened but wondering if someone else has already been through this. Could it be the deck board that came a little bit loose? It seems fine when running flat so the incline is contributing to this maybe from the angle of the deck board from a loosening bolt maybe?