I've been hearing what I thought was a lifter tick for a couple months now.

I got some Marvel Mystery Oil and put it in the oil to see if there would be any change in the noise. The noise became slightly quieter.

I poked around with my mechanics stethoscope and the only thing I heard that sounded close to the ticking I've been hearing was the fuel injectors but they were a pretty steady click and the ticking I've been hearing was between 1000rpm and 1700rpm (before the exhaust drowned it out).

I poked the borescope around and found out that the passenger header had a cracked weld, I fixed the driver header for the same problem a couple years ago.

I went down to my dads house and got my old manifolds then cleaned up the mating surfaces and put them back on the truck.

The noise is almost gone now and the power difference is about the same as when I upgraded my gears from 3.55 to 4.10. The engine is a lot quieter now too, I can barely hear it and that makes the exhaust sound a lot better since it's about all I'm hearing. The leak crept up on my so slow that I didn't notice it until it got really loud. It was weird that it didn't have the pfft pfft pfft sound that is associated with an exhaust leak.

I was surprised on that the bolts on the driver side flange had 5ft. lbs or less holding them too, I think that might have been the major leak that I was hearing. I'm probably going to have to get back in there sometime soon and put some donut gaskets on there because I couldn't find my originals and it looks like it needs them.

The tangs that hold the heads of the flange bolts were rusty and mangled so I had to improvise




Once again, if you have headers with the big loop in the rear pipes then you should modify a wrench like this because it'll save you a headache