I went to a tire shop to balance some wheels. A few days later I had to take off my front wheels to change brake pads. These clowns from the tire shop torqued my wheels down so tight; I couldn't get the lugs off. The cover on the bolts caused the lugs to be stripped. has anyone had that experience?

 

Personally, no. As I only take the wheels, not the car to a tire shop.
But there are lots of threads on this, just search this forum for ‘lug nuts’. Here’s one to get you started:

Lug nuts

 

There are two common issue at hand
1. Many shops do not use the correct metric sized socket.
2. Rarely do independent shops read the torque settings.

Fessing up, I did go to a cheap tire source once, many years ago. And never since.
1 Ruining the 2 part nuts
2 Marking up the wheel and insisting it was the fault of the low profile tires I selected for installation
3 Marking them up a second time when balancing the wheels and not using the adhesive weights on the inside of the rim.
4. I have to tell them how to lift the car with a hoist.
Nope. Never since. Never again

 

to get them off you have to remove the outer casing punch a hole dead center trough the casing and use a pair of needle nose pliers to remove the casing be care full not to scratch your wheels !!!! use the next size smaller socket and take them off you might have to force the smaller socket on then order stainless steel solid lugs and you will never have this problem again there called swollen lugs see it all the time Ran

 

To convert the lug nuts to the standard common lug nut, what would be the best size to use?

 

Stock Toyota ones; there is at least one lengthy thread in here with part numbers, sizes and all that info.

 

these are the ones

you need

 

If they are actually OEM, they are the junk two-piece nuts that should never be used, ever.

 

there on my xkr right now they are solid stainless steel one piece

 

The seller’s eBay ad says that they are SCM steel. The "SCM" in the designation stands for "steel, chromium, molybdenum."
A Japanese standard, although it doesn’t say what grade it is.

 

i like them they went on fine look good you have to make your owe decision on what you want

 

X00217 1B9X under barcode on box Part no. MIKKUPPA QLN037 12 x 1.5 size ~1/8 inch longer barrel/thread engagement. Requires larger 21mm socket.