60 Series Gear Noise, or ?

Coming through Salt Lake last week I picked up on a noise that clearly mimicked an idler gear not set correctly. But that doesn't just happen going down the road.

So I pulled the accessory drive to check the bull gear. Nice and tight. Put it back together and delivered, and drove it home.

So i go to checking it out. I had recently replaced the cam, injectors, and rocker assembly, so i pulled the valve cover and inspected everything. All good.

Drained the oil and found this.

Decided i had to have a problem with the bearing in the bull gear, or the bushing in the idler gear. So i pulled the front cover this morning. Bull gear is fine, idler is fine. Gear lash was also ok.

Anybody seen anything like this before? I've worked on a bunch, but never seen a gear like noise start while going down the road. Water pump and air compressor are tight and smooth turning, and both were replaced in summer. Guess i'm pulling the pan next, but though I'd ask.

 

It was gear noise, but from the oil pump. Found the bushing in the pan.

 

Me neither, which is i went into the front cover. All good. New front structure, cover, bull gear and oil pump. I'll rebuild the fan hub, and shouldn't need to mess with the front for a while

 

Yep. Might have lost a PSI or three, but nothing extreme. Probably accounts though for the stumbling jakes I would notice at times.