A very basic question: how do you measure a wheel to tell if it is 5 on 4 or 5 on 4.5?

On a 5 lug wheel, pick a lug, then count two more lugs around the bolt pattern (i.e. ouf of 5 lugs use #1 and #3). Measure them center to center with a tape measure to see if they are 4" of 4.5"...You also can take them to your local tire store and ask them what bolt pattern they are (they should help for free, thinking that you might be interested in a new set of rims...)

-D.Idiot

I thought it was from the center of the lug to the far outside edge...I could be mistaken.

-josh

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64 Dart 170 /6

No. The bolt pattern is measured by measuring the diameter of the circle the bolts make. On a 4 bolt wheel this is easy... just measure center to center on two opposing wheel studs. On a five bolt you have to scribe a circle through all the stud centers and measure its diameter. This degree of precision is only necessary when trying to match offbrand wheels to your car, and then you have to look at backspacing. I just take my worn out front hub with me and try to drop it in to the wheel. You will eventually be able to visually distinguish Chrysler bolt patterns as you become accustomed to it.

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I've been calling it as i see it for my entire life and that's not about to change. Take it or leave it.

Stud to stud on a 5 bolt wheel is going to fall short of the true diameter of the circle, so don't get fooled. I like to go from the center of the wheel (or hub/axle) to the center of a stud to find the radius (2" radius = 4" circle, 2 1/4" radius = 4 1/2" circle).

Thanks for the tips!!