Technical How to measure your bolt pattern

I've had this saved for a long time and thought it might be helpful to some of the newer guys. HRP


Have you ever bought a project car or even a completed car that was the brainchild of another hot rodder? Sometimes, you never know what type of suspension or brakes are used in a project car, but it’s pretty common to have mis-matched bolt patterns. For instance, it’s common to use a Camaro or Nova subframe and front suspension, which features a small five lug GM pattern, measuring 4-3/4 inches. And let’s say they robbed a Ford 9-inch out of an old F-100 pickup, and it still had the stock five lug bolt pattern, which measures 5-1/2 inches. If you’re unsure about your bolt pattern and you’re on the hunt for a new set of wheels.

In most cases, American automobile manufacturers used a five lug bolt pattern, starting in the late ’20s. The five lug pattern remains a common trait for passenger cars and light trucks, even in modern automobile manufacturing, but every company has a different approach. For instance, General Motors had two common bolt patterns, 5×4-3/4-inch and 5×5-inch. The smaller pattern is extremely common, as Camaro, Corvette, Chevelle and many more GM makes and models featured the 5×4-3/4-inch pattern. The larger pattern was used for light trucks, as well as many full size cars in the Buick, Oldsmobile and Pontiac lines.


On the Ford Motor Company side (including Mercury and Lincoln), it also comes down to two common five lug bolt patterns, 5×4-1/2 and 5×5-1/2, although Ford did produce a few passenger cars with 5×5-inch bolt pattern. The small pattern, again, was mainly used for mid-size and full size passenger cars starting in 1949, such as Fairlane, Galaxie, Torino and more, while the larger 5×5-1/2-inch pattern was used for light trucks. Also remember that the 5×5-1/2-inch pattern was common for early Fords, ranging from 1928 to 1948, with the exception of “wide 5” hubs, which were only available from 1936 to 1939. Wide 5 wheels are very easy to identify, because of the extremely large five lug bolt pattern–5×10-1/4 inches to be exact. Wide 5 wheels are pretty rare, and there are no reproductions of these wheels currently on the market.


Finally, we end this bolt pattern lesson with Mopar, which used 5×4-1/2-inch bolt patterns for many of its vehicles for quite some time. The only exception is the smaller 5×4-inch bolt pattern, which was used on smaller vehicles such as the Plymouth Valiant and Dodge Dart. One difference in a typical Mopar application is the center hole is typically smaller than that of a Ford wheel, even though the bolt pattern is the same. Also, it is important to note that many Mopar applications from the ’60s and ’70s had left-hand-thread and right-hand-thread lug nuts for each side of the car.

So, how do you measure the bolt pattern? It’s easy. Grab a tape measure and measure from the outside of a wheel stud, to the center of the third wheel stud. See the illustration for an example, as it can be tricky, since there isn’t a precise measuring point on a five-lug hub. Now that you’ve learned about wheel bolt patterns, put your knowledge to use the next time you visit a swap meet.

 

Good thread. When I was getting read to order my new wheels, I went to measure the bolt pattern and almost got the wrong wheels, by measuring wrong.

 

Always good information to have on hand.

 

Of course I try to keep one of these handy in case my measuring skills are a little suspect.

 

Such a simple thing so many get wrong

 

Once I realized my error, I measured mine 4 or 5 times! THEN, one more time before I hit Jeg"s "submit order" button!

 

Add the terms and details for what and how to measure back space on wheels to this thread.

 

I've got one of those things Don pictured. Makes life easy when used wheel shopping.

 

I have a few of these. Needed different ones at different times. 5 lugs, 4 lugs, metric, and there are ones for 6 and 8 lug.
Like reading glasses there are some in each vehicle that might go to flea market. Then you go with your friend and have to buy more so you buy the right wheels!

 

very helpful information , thanks for posting it up HRP

 

From Jeg's:

http://www.jegs.com/images/wheelmeasureguide.pdf

Tire & wheel calculator:

http://www.rimsntires.com/specspro.jsp

 

I'm like Lothiandon1940 in that I found this little plastic gizmo on the table that a swapmeet cheapie tool vendor had. He had several different combinations be they 4 , 5. 6 or 8 lug. about 4 bucks.

I've got an aluminum one I got off Ebay a few years ago that slides right in my hip pocket to carry when I might check the lug pattern on a wheel or axle.

 

Don has it....you can buy those at just about any swap meet...those little red plastic wheel bolt space make nice X-mas gifts....missed a few.... Chevy was six bolt early on - for cars and trucks....cars to about 1948....others that ran the 5 on 5 1/2 - Lincoln / Imperials and Willis/Jeep.....

 

This one is great. No mistakes.




Sent from my iPhone using Tapatalk

 

Learn something everyday - on 5 lug wheels I always thought the 'bolt circle' referred to the ACTUAL diameter of the circle not the the center-to-center of the furthest apart lugs!

 

It does refer to the circle on 5 lug wheels. center to center on 4, 6 and 8 lug wheels.

 

Cool! Just ordered one only $10 CDN shipping included from Amazon Canada.

 

............Just to clarify, it's not the center-to-center of the furthest apart lugs, but the center-to-outside edge of the furthest apart lug hole. Look closely at Danny's examples above.

 

This is sort of a worksheet some might find useful when trying to determine what backspace or offset you might need for your particular application. It could help when you call up a wheel company with your needs. Taken from an old Wheel Vintiques catalog.

 

Exactly, and there-in lies the reason for years of confusion. It just goes against common measurement fundamentals we were taught as pups...

 

OK.....I learned TWO things today!!!

 

The tool Don pictured on his post is really useful. Ordered the 5 lug US one off the auction site today for $7.50 including shipping. Easy to carry and cheap insurance against mis-measuring and buying a wheel you can't use. Thanks for the heads up guy's.

Gary

 

Like everything else in this world even the cheap swap meet tools are more costly,I looked at the one I bought at the swap meet at least 20 years ago and I believe I paid a dollar for it,the guy had a big box full of them. HRP

 

Good FNG lesson, HRP.

Singlefinger Speed Shop,
still lurking around Detroit

 

Inflation Danny. I think I payed $3-$4 for mine 5 or 6 yrs ago.

 

From axle or hub center to stud center using my Steve Austin eye. But in my case, I need a tape measure because my eye wasn't equipped with a measuring software.

 

As "1940" mentions and illustrates in post #20, the pattern on 4, 6, 8 lugs are measured center of lug to center of lug, whereas 5 lugs are measured center of lug to outside of lug (as illustrated in Danny's O/P.
When going to swap meets, I always carry a small pocket tape measure and a paper stock lug pattern folded up in my wallet because it's easier to pocket than the plastic disc.
You can print one on heavy paper stock here;

http://www.easternmarine.com/tech-info/wheel-hub-bolt-circle-template/

(click on the pictured template for a full size PDF)

 

It does refer to the circle at the center of the studs but since there aren't two directly across from each other, center to outside of those two is nearly identical to the circle diameter. Different size studs change the measurements slightly but they are close enough.

 

On 5 lug bolt patterns, I just measure center to center (or edge to edge) and then add 1/4" to arrive at the lug bolt spacing diameter. Find this the easiest way to remember.