lug bolt pattern

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Mar 5, 2009 | 10:29 AM

taonindo

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Car: 82 firebird

Engine: 406

lug bolt pattern

tire shop is telling me 3rd gen is a 5 on 4.75..but i measure it to be 4.5...am i measuring wrong? it is center to center right?

Mar 5, 2009 | 11:24 AM

DJP87Z28

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Re: lug bolt pattern

Quote:

Originally Posted by taonindo

tire shop is telling me 3rd gen is a 5 on 4.75..but i measure it to be 4.5...am i measuring wrong? it is center to center right?

You can not measure a odd number B/C center to center. The correct B/C is 4.750

Mar 5, 2009 | 11:30 AM

taonindo

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Car: 82 firebird

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Re: lug bolt pattern

that makes sense...thank you. after 2 hours of searching i think i knew every thing but that...lol...thanks agian

Mar 5, 2009 | 11:31 AM

Stephen

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Re: lug bolt pattern

center to center & 4.75" is correct

Mar 5, 2009 | 01:35 PM

AlkyIROC

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Re: lug bolt pattern

You measure across 2 studs like you were doing but you measure differently. From the outer edge on one stud to the center of the second stud will give you 4.75.

Small GM bolt pattern has always been 4.75". The large GM pattern is 5" found on pickup trucks and the larger model cars.

Ford and Dodge small pattern is 4.5"