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what looks good, I have a 2006 ext cab

I found some wheels but they are

Size: 20x9

Bolt Pattern: 8x170mm

Offset: 30

Finish: Triple Chrome Plated

Hub Bore Diameter: 5.125


duuno what this means
 

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From: CustomTacos.Com

Wheel Backspacing and Offset



Before mounting a set of aftermarket wheels, there are some dynamics involved with fitment that are best to understand first.

1. Wheel Diameter. This is the diameter of the wheel. Stock wheels are commonly 15 or 16 inch diameter. This dimension is usually in 1 increments (i.e. 15, 16, 17) but some manufacturers offer 16.5, which is rare.

2. Wheel Width. This is the width of the wheel, measured inside the outer lip of the wheel. This dimension is usually in 1/2 increments (i.e. 7.5, 8)

3. Wheel Center. This is the center of the wheel in relation to the width.

4. Offset. The distance from the centerline of the wheel to the face of the mounting surface of the wheel that contacts the hub.

4.1 Zero Offset. Indicates the mounting surface is at the wheel center.

4.2. Negative Offset. Indicates the mounting surface is behind (or inboard) the centerline of the rim. This is often found on standard rear-wheel-drive vehicles and on so-called reversed rims. (Diagram below shows negative offset)

4.3 Positive Offset. Indicates the mounting surface is in front of (or outboard) the centerline of the rim. This is often found on front-wheel-drive vehicles. Stock Tacoma wheels have Positive offset.

5. Backspacing. The distance from the mounting surface to the inside lip of the wheel. This measurement is closely related to offset (without actually measuring, backspacing is about equal to [Wheel Width / 2] + [Offset] + [about 1/4] ).

6. Centerbore. The centerbore of a wheel is the size of the machined hole on the back of the wheel that centers the wheel properly on the hub of the car. This hole is machined to exactly match the hub so the wheels are precisely positioned, minimizing the chance of a vibration. This measurement may be critical to clear the hubs of a 4WD.

7. Bolt Circle. Also known as PCD (Pattern Circle Diameter). The bolt circle represents the diameter of an imaginary circle that goes through the center of the bolt holes. 4x2 Tacoma Bolt Circle: 5 lug on 4.5 PCD; 4x4/Prerunner Tacoma Bolt Circle: 6 lug on 5.5 PCD.


 

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what looks good, I have a 2006 ext cab

I found some wheels but they are

Size: 20x9
The diameter which is 20" in your case is the straight across beadseat-to-beadseat distance, not the outer edge distance. The width (9") is the distance from the front bead seat to the rear bead seat, not the outer measurement of the wheel.

Bolt Pattern: 8x170mm
The number of bolt holes (8) in addition to the centerline of one hole to the centerline of the one farthest from it. (170mm)

Offset: 30
This is a tricky one, I'll do my best. The relationship of the wheel's mounting pad to it's centerline. The mounting pad is where the wheel meets the hub assembly. Zero offset is when the mounting pad is centered on the wheel. Negative offset, which is mostly common when upgrading wheel width is when the mounting pad is more towards the center of the vehicle. This makes your wheels stick out of the fenders more. A positive offset is just the opposite, it stuffs the tires more inside the fenders. Is your offset positive or negative? This is most commonly measured in mm.

Finish: Triple Chrome Plated
Prolly steel, but ask.

Hub Bore Diameter: 5.125
This is the diameter of the hole in the center of the wheel.


duuno what this means
My advice is go to a local tire store with the part # of the wheels and ask if they will fit. Hope this helps, If not please let me know.
 

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Thanks guys! learned it!
 

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I think my MKW wheels have THE PERFECT offset for 05-07 Superduty... I would try to get wheels that matched that if it could be found out what they are.
 

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This thread came up in my search for information on offset and backspacing specs for my 2005 Excursion - sounds like some good information from very knowledgeable sources! My SUV came equipped (pre-owned) with what I assume are the 5-spoke, 18-inch factory rims from an F350; the inboard rims were rubbing the front springs and the rear wheelwells. I added 2" spacers to provide better clearance, but I'm getting flak from the wheel/tire shops about working on vehicles with spacers. Given that the Excursion is based on the F250, do they share the same wheel specs vs. the F350? If that is the case, my intent is to find a similar set of 5-spoke, 18-inch rims from an F250 and to eliminate the spacers. Thanks for your help!
 
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