Loud Ticking 03 Tundra
A little history. I put on headers a couple months ago so I know it's not an exhaust leak, it at least it should not be. It also sounds different than when I had the stock exhaust manifold on that was cracked. I recently had my radiator replaced and my transmission flushed 3 times because of the transmission cooler leaking into the radiator contaminating my transmission. The transmission shifts great for now, hoping it stays that way but doubt it. Since I got it back it's ticking, even when it's warmed up. It's loud, you can easily hear it inside the cab when giving it gas. It's been very cold where I live, -1 this morning. You can hear it when first started and goes away about a couple minutes of idling but you can always hear it when you give it gas. I checked the oil, looks find but might be a little overfilled, could that be it? I also put 91 octane gas in it not knowing I should feed her the 89 or 87.
I've heard these engines like to tick, specially in cold weather but it did not do this before I had the radiator replaced. When I pass a wall, it's super loud.
Does this sound like engine slap or valve lifting? Something I should be concerned about?