I would think the lean code would be caused by the shorter push rods too, as in the valves not fully opening, but it could be something else...

 

So I'm getting it apart.
On base circle from zero lash...its 1/4 turn till 22ft lbs.
So not much at all

How do I test the lifter?
See if it squishes?

 

1/4 turn? Shouldn't it be more like 1-1/4 turns?

 

So that 0.25" made a difference there for sure.
I pushed on all the lifters. Couldn't squish any

 

https://www.youtube.com/watch?v=dndE...e_gdata_player

Here's an idle warm in the shop. The valve train does sound good at idle. I'm nervous to open it up though

 

https://www.youtube.com/watch?v=TbIB...e_gdata_player

So the damn noise came back...
Check engine too. I'm getting
P0171 lean bank 1
And
P0521 engine oil pressure sensor performance
The second one is new

 

Freeze frame the 0171 came on at 784rpm and at engine load 35 percent
The 0521 came on at 1682rpm and at engine load 40 percent

 

Sitting here idling checking it with the solud scanner. The noise has conpletely gone away. But returns if I put it in 1st and get going to about 3500rpm
So at cruise my noise is fine. Its like it cmes on after I get on it hard

 

Can ya post a vid at idle and at 35k engine bay

 

Here
https://www.youtube.com/watch?v=pVWRqS5f_2U&feature=youtube_gdata_player