I've got an 02 F150 6cyl that has an intermittent rattle, mostly at idle speed. Could it be a rod? Could it be something else? Any ideas?

 

Hard to say without hearing it.

 

Hard for me to say even after hearing it, lol. I guess what I'm asking is if a rod knock could be intermittent and only heard at low rpm.

 

I don't want to say all rod knocks are limited to my experiences and I can only tell you about my experiences. Rod knocks are limited to they are or they aren't. At idle the knock is slower and quieter. As RPM's go up the knock gets faster and louder with momentum and velocity. As I said though, my experience doesn't mean someone else can't contradict this.

I can say I've never heard a rod knock sound like a rattle. Do a search on you tube for rod knock and see if what you're hearing matches what's in a video. A rattle usually comes from something like an exhaust heat shield.

 

Thanks for the input.