How much of the lug bolt should stick out of the back of the wheel? Too long can destroy brake parts, right? Too short and your wheel isn't attached well enough, right? So how much bolt is the right amount to thread in?

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William Weatherby

Whatever the car came with.
But if you need to measure what you have, remove the rear hub, depending on what car you have, not a big deal.
Then using the bolts you have, mount the wheel and measure. You don't want the bolts to stick through, as you mention. This is only for the rears, but don't go crazy in front either.

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83 SD

84 CD

The bolts that came with your car work great with the wheels that came with your car. When you get different wheels, you might need different bolts.

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William Weatherby

The lug bolts appear to protrude 16mm out the back of the stock wheels. Does this sound right?

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William Weatherby

Mount the rear hub to the wheel off the car, then measure.

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83 SD

84 CD

Yes, 16-17mm is correct.

proper is 12mm or about 1/2in