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Getting a new Terrain in a few weeks. I'll be changing the 18" factory wheels with something from Tire Rack or Next Wheels. I'm learning about two measurements called Backspace and Offset. They have something to do with whether or not the wheel will hit the calipers or wheel well. Also will determine how far out the wheel sticks out from the well.

When I search the wheels offered on these sites filtered for a 2011 Terrain I get several model wheels with various Offsets (.35mm, .38mm, .40mm, etc). A question I have is what happens if I were to order a wheel with an Offset other than what the factory wheels are - will that void the warrantee? Will the vehicle perform differently or will there be a safety issue?

I sure hope I don't have to pick a wheel with an offset equal to the factory wheels. That would reduce my selection considerably. (incidentally, what is the offset of the 18" factory wheels?)

Help?

Thanks for you help.

Robterrain
 

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offset will push the wheel further away from the hub......so the tires will stock out past the fender if your offset is too much.....if your changin rim/tire sizes you will most likely need to change offset as the width is now different and you need to compensate....

dunno the offset on the wheels....a call to the dealer, or a swing by a local tire/wheel shop would solve a bunch of questions im sure....
 

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robterrain said:
I sure hope I don't have to pick a wheel with an offset equal to the factory wheels. That would reduce my selection considerably. (incidentally, what is the offset of the 18" factory wheels?)

Help?

Thanks for you help.

Robterrain
I'm sure its different than the 19's so I don't want to guess if give you the width and offset from the 19's.
But if you look from the inside of the wheel, wheel size should be stamped on the backside of one of the spokes. Should be 3 sets of numbers there.[/color]
 

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Maybe, probably, depends on the offset.
 

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If you look inside almost any wheel you’ll find spec stampings.
An example is...18x7JET38. 18 represents the wheel diameter...
The 7 is the width of the wheel which is the distance between the flanges that support the beads of the tire...
The J represents the shape of the flange...
The ET stands for a German term which translates into offset...
The 38 is the offset.

Next you should look for Hub Centric rims.
They are designed to fit closely/exactly over the rounded center portion of the hub and help support the vertical weight and center the rim over the spindle axis...


Factory rims generally are specific to hub centering...as are some aftermarket rims
Some aftermarket rims use/supply "hub centric" rings which are tapped into the center hole of the rim to center the rim over the hub

Offset is the location of the flat mounting surface of a rim relative to the wheel’s centerline. Negative offset moves the rims mounting surface toward the center of the car...
Positive offset moves it away.

Too much positive offset will lead to problems...rubbing issues when the suspension is under compression...turning full lock...scrub radius...torque steer and self-centering after a turn...suspension motion ratio as it relates to spring and damping.
Wheel bearing and hub wear can also be affected if the center of mass is moved to the outside too far.

You could void the warranty on select components if your rim selection has an affect on the aforementioned areas.
 
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