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Discussion Starter #1
I found a set of bmw spec'd wheels that I like and was curious if any one would know if they would fit. The specs are 18x9.5 with a +10 offset
 

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You'll possibly have 2 issues.

A 9.5 inch wheel has an overall outside dimension of 10.5". Half of that is is 5-1/4". Add the 10mm offset and I get a backspacing of 5.643 inches. That might hit the ends of your tie rods on a 2wd. I know the 15x7 GM 4wd wheels have 6" back spacing and they aren't even close to fitting on a 2wd. Those BMW wheels have only 3/8 less backspacing. Your stock 2wd backspacing is 4" on a 15x7 S10 wheel. 4-1/2" on ZQ8 16x8's.

The other issue is the difference in bolt pattern. BMW is 5x120mm (4.72mm). S10 is 5x4-3/4" (120.65mm).
There has been and is two schools of thought on the bolt pattern.
One is they will bolt on so run em.
The other is "Not on my truck".
There have been endless discussions about machining tolerances and metal stress and fatigue.
There have been endless discussions about "I'd only kill myself" vs. "Yeah, and my family too if they're on the same road when your wheel comes off"
Hopefully your question won't ignite this AGAIN.

I personally am a cheap SOB, so if I had them I'd try them, but I wouldn't spend much money for something that almost fits. There are a lot of choices that do fit. For 30-40 years the 5x4.75 wheels were the most common wheels on the road. Not recently, tho. The rise of the foreign cars muddied the water with all kinda bolt patterns.
 

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Randy
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Remember a wheels size is measured in side the bead whereas the back spacing is based on outside width. Since most current wheels a JJ's the bead is 1/2" thick on each side. An 8.5" wheel has an outside width of 9.5"
Conversely if someone is selling 9-1/2" wheels take along a tape measure because a 9.5" wheel is 10.5" outside.
You need to remember this when comparing offset (MM's) to backspacing (inches). An inch is 25.4mm.
S10 4wd wheels are offset 51mm or exactly 2 inches. 2wd are 0.
 

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Don't put 120mm wheels on a 4.75" bolt pattern, you will likely experience what loosing a wheel feels like.
 

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Discussion Starter #7
Remember a wheels size is measured in side the bead whereas the back spacing is based on outside width. Since most current wheels a JJ's the bead is 1/2" thick on each side. An 8.5" wheel has an outside width of 9.5"
Conversely if someone is selling 9-1/2" wheels take along a tape measure because a 9.5" wheel is 10.5" outside.
You need to remember this when comparing offset (MM's) to backspacing (inches). An inch is 25.4mm.
S10 4wd wheels are offset 51mm or exactly 2 inches. 2wd are 0.
Thanks. My blazer is 2wd it's an xtreme
 

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I turn.
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I've been following the 5x120 vs. 5x120.65 debate for 15 years and used to swear against running BMW wheels. I've given up - on the multiple forums I frequent, I've only seen one actual example of a failure on a high horsepower pro-touring car running drag radials and stock wheel lugs and it likely wasn't the wheel's fault.

I run 5x120's for my daily VMR wheels on my F-body using ARP lugs and am currently swapping my front end to C7 hubs, which have a 5x120 pattern that I will run with 5x120.65 wheels. There are literally hundreds of things I would worry about more than a 0.13 mm bolt hole tolerance on 99% of old GM products.
 
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