2006 5.3 no power mid rpm

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Camar068

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K10/LM7 5.3/4L60e/np208/3.73/32"
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10 yrs Air Force
So I've got an issue with the LS swap I did about 4 years ago. Little history:

-had about 115k miles (has guessing 190k now)
-came with 4l60e trans

Anyway issues below:

-keep ur foot in it it's fine
-cruise.....it seems to lug guessing 1500 - 2200 rpms (by lug I mean....it will not gain 10mph in no less than 20 seconds)
-get up passed guessing 2200 rpms.....it's ready to go and responds

The trans seems to be shifting fine, fluid smells good.

Oil pressure above 30 always

I've changed MAF sensor, checked for vacuum leaks, removed air filter, and checked fuel pressure. One thing I did note was "pure" oil in my catch can. Normally it's a milky oil (oil/water mix).

Today I flushed the pcv input on the valve cover and now I have a significant knock/tap. Old trick, I took some tubing to my ear and touched all over the engine and can't find the culprit of the knock.

While under the vehicle, the knock/tick didn't come from the flex plate/torque converter.

This evening I put seafoam in the oil and noticed right off the bat that it was smoking more than normal.

Engine does not lose oil unless I'm in the mountains for a while.

I'll pull the covers in the next few days to check for loose rockers (bad lifters/push rods) and check the compression if nothing obvious (leaning lifters due to exact sound seen on a few utube videos)

Other wise, sounds like bottom end/rings right?

One thing I haven't done is checked all my grounds.....but at this point with the knocking I don't think thats gonna be it.

Thanks

[edit] about 5:20 is what I'm hearing but a little deeper at times during idle

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Camar068

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10 yrs Air Force
RPM power slug is probably around 1200 instead of 1500
 

Camar068

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K10/LM7 5.3/4L60e/np208/3.73/32"
Engine Size
10 yrs Air Force
pulled valve covers and nothing was loose. I didn't realize it would run with a full bank unplugged until I got the passenger side back together and forgot to hook up the spark plug wires.

Rockers moving on drivers side.

I'll pull it again and run it to look for movement.

After that is oil change (since I put seafoam in the oil) and then compression test.
 

Camar068

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K10/LM7 5.3/4L60e/np208/3.73/32"
Engine Size
10 yrs Air Force
compression looks good compared to when I installed the engine. Good to know the top end is good. Off to trans shop to check flexplate. With ~190k Miles....I can deal with a rebuild while he's looking at it.....if it's the flexplate.
 

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