I was leaving for work this morning and shifting from 2nd to 3rd My car suddenly started to make a loud sound like my muffler had come off I took it to the shop and they told me I blew a plug out of my engine and stripped the threads has anybody heard of this happening before and what is the best fix

 

Oddly enough this happened to my son's 2007 F150 with the 5.4 Triton recently.

I never heard of this happening until it happened. I was away on a business trip so I couldn't inspect it myself.

Symptoms were a loud bang or pop followed by a rattling sound.

Never got an explanation as to why it happened.

 

I have also heard about this on ford trucks also. Never have heard it on a Chevrolet product

 

Mainly on Ford products but haven’t heard this happening on a GM….there are kits for this repair.

 

It’s happened two me TWICE on my 2001 c5. Easy fix but a pain in the ***. I now have 270,000 on the clock.

 

What was the fix and how much did it cost?

 

my corvette mechanic used a helix insert which then became the new threaded tap. Evidently the LS1 uses the same procedure for all of its plugs. I don’t remember the cost, but at that time it wasn’t expensive.

 

I've used this one before on all kinds of engines. Outboards mostly. Just make sure its the right thread:
https://www.napaonline.com/en/p/BK_7703223
Pack the flutes with grease to avoid chips getting in the cylinder. Go in and out several times cleaning the chips and grease out of the flutes each time. A few small chips of aluminum in the cylinder wont hurt anything, Just do your best to minimize chips falling in the cylinder. Easy fix if you can see what you are doing. Alternative is pulling the head.

 

A few small chips could get stuck next to the piston?

I know this has been done, but seems sketchy IMHO.

At the very least vacuum out the plug hole

 

I'm not going to get into urinary jousting...
A vacuum will not get inside the cylinder, hence my comment about the small chip issue.
Yes, I've done this repair myself, many, many times. Most common in my life: The 2-stroke outboard plugs get stripped from the threads having 2-stroke oil and/or fogging oil on the threads, making a lubricated torque when all they have to do is crush the gasket when tightening the spark plug. Typically this is owner induced when squirting fogging storage oil into the cylinder at the end of boating season. The last time I personally did this repair was the forklift at work when the "Certified" hired forklift mechanic over-torqued a spark-plug, stripped the hole, then walked into the office and quoted us $2500 to yank the head. I had the spark plug hole fixed fixed in less then an hour for less than $50 using that NAPA kit (easy access). I've seen all kinds of crap go through engines. A few small chips of aluminum? Ideal? No. Will a few chips hurt anything and most likely get blown out the exhaust, with out damage? Probably. I would not lose any sleep over it. Do your best, and pack the flutes with grease, run the tool in and out cleaning as you go, to keep any contamination to a minimum.

Other cleaner options:
You could always bore-scope it and make sure its surgically clean when your done. Although I'm not sure what you would use to get in there and remove chips? Wire with a dab of grease perhaps?
Safer yet, yank the head, and use a Bridgeport to get the correct angle on the hole. Drill, STI tap, Helicoil/threaded insert, with red locktite holding it in place. This is the cleanest, most accurate way to repair the hole. Also the most $$$ expensive.
Whatever turns your crank...

 

you can use a vacuum and a plastic tube taped to it and suck out 99% of the chips,ive fixed engines like this for 40 + years