I will suggest cutting open your metal oil filter can and open up the filter pleats inside to check for metal debris.

Rick

 

Drive in M5 all the time so AFM won't activate until you can diagnose this further. Something needs immediate attention.

Do you feel any kind of vibrations or shuddering? Have you ever changed your transmission fluid?

 

I would disable the AFM for sure, using the method being discussed in another thread. The VLOM plug and gasket cutting with the OBD2 disabler. Couple hours work and under $100.

Another option is to drop $3500 on a full engine rebuild with the AFM delete kit, new cam, new lifters, tune, etc.

But if you dont stop that noise right away, your will cause lots of damage to the engine.

 

Transmission is doing fine, and I know I'm on borrowed time with it. Trans fluid has never been changed and it's too late now according to my trans shop.

Not driving it all, next in line at the shop for diagnosis. They are thinking rod knocking, but I would think that would be continuous, or could the AFM cycling cause a spun bearing to knock Intermittent?

 

100% AFM lifter failure that sounds exactly like my old neighbors Tahoe before I helped him do an AFM delete. Every time you hear the thud that is the lifter impacting the cam.

 

EDIT: My threads were merged so I lost the title.

5.3L Reman or Crate Engine Costs

Curious of any experiences here, I may be headed this route pending final diagnosis any day now.

Mine is a 2015 but any 5.3 experiences welcomed. I will be putting the truck up for sale, so thinking reman.

Thanks

 

I'd do a local rebuild with a reputable shop for possible warranty claims.

Rick

 

What's wrong with it that it needs engine work?

 

.

 

Update. After many lengthy discussions the shop finally got to it for diagnosis. They have never ran across this on and off knocking in V4 mode only. Their suggestion was to program it which they can do to stay in V8 mode and just drive it.

I opted to order the plug in disabler so I would have full control. Engine purrs like a kitten at idle and sounds fine in V8 mode.

Still a dilemma as I want to sell the vehicle. I will be cleaning it up and see what my options are without too big a loss.

KBB $14k to $17k.
Full AFM delete kit $6k.
New (not reman) crate engine $10k.

 

Pull the oil filter and cut it open then lay the pleats out flat and inspect for metal. You can get a magnet and wrap it in plastic and swirl it around, in, and over the filter or drained oil. If you find a lot of metal stop driving it and just repair the cam/lifters or delete the AFM system all together. You do not want to keep running metal or possible lifter that is going bad around. If you destroy the journals that means total engine replacement.

 

Good luck with your decision

 

If keeping I would use the OBD2 plug in. If selling, I would have it disabled int he ECU and list it as "AFM disabled" This will prevent the new buyer from accidentally knocking the OBD2 plug in onto the floor and then running into engine problems.

 

So to update this, I dropped it off at the dealer. My goal was to get their opinion and pinpoint the failure of this more unusual symptom than most. Ended up this could not be done, without going in. Only thing for sure it was on the passenger side.

While not popular and I was tired of worrying with it, pulled the trigger on repair with factory GM parts. There was no smoking gun of the bad lifter, I wanted to hang that thing in my shop on a plaque.

All in, new lifters, volm, and associated parts, gaskets, etc., $6k. Cam was good as no lifters had rotated in this instance. Oddly, appears to hang in V4 mode longer now than before but all is well. I have a plug in AFM delete but will drive as is for now.

Still tweaking on this unit before she goes up for sale. Very sad to see it go, love this truck but no room in the yard or my wallet to have two like this.

 

Thanks for the update. For informational purposes, how much $$ would you have gotten for the truck before the repair? How much after?

 

I figured it was unsellable like it was, I know I wouldn't have bought it.
KBB with issues $14-17K.
KBB excellent condition $19.5k