Wheel offset question

[dkad260]

I wanted to start a new thread in case others needed to search this, and not have it buried in another thread I have going here with regards to changing wheels.

Need help debating new wheels

I love the optional OE 22" wheels on our 2012 Denali, but.....after replacing 2 already, I have the other 2 leaking air at the bead, forgive the dirty wheels, been cold and nasty here. Maybe if I can find 2 more I will keep them, but they aren't cheap, IF I can find them. Bead sealing...

www.tahoeyukonforum.com

My 2012 Yukon XL Denali apparently came with the 22" wheels, assuming it was ordered that way. I have been thinking of going with 20's or even 18's and the question I have is about the OE offset of 31MM and how far the tire protrudes from the fender.

Is it normal to have the outer edge of the tire protrude past the outside of the fender? Granted it's only a small amount, but I don't see this on other vehicles.


This the OE 22" wheel with 31MM offset.

When I tried the 18" wheels from a '22 Silverado with 26MM backspacing, the protrusion was worse and that's with a 1/2" narrower wheel.

This is the 18" wheel with 26MM offset and also a 1/2" narrower wheel.

Is this normal for the GMT900?

The 18" Tahoe/Suburban wheels of this era have a 24MM offset and those I would assume would protrude even more. I'm trying to get an idea if any wheel I choose other than the OE 20" or 22" will even look right in terms of how far they stick out from the fenders....especially the front fenders.

Feel free to post up pics of your tire/wheel swaps of OE sizes and how they have worked or haven't worked.

 

[dkad260]

Now that I think about it, I had replaced both front hub and bearing assemblies a couple years ago, could I have been given the wrong parts? Are there different hub and bearings that vary the mounting position of the 1500 GMT900's? I didn't think to verify the OAL of the new ones to the old.

 

[swathdiver]

The CK910 22" wheel has a 24mm offset. I liked them tucked into the wells. GM also used 20 inch wheels with 22 and 27 mm offsets. The most prevalent being 31mm.

 

[5StarCustmSolutns]

Now that I think about it, I had replaced both front hub and bearing assemblies a couple years ago, could I have been given the wrong parts? Are there different hub and bearings that vary the mounting position of the 1500 GMT900's? I didn't think to verify the OAL of the new ones to the old.

Thats a good question..

I'm gonna guess the answer is: No ....or at least if there are H & B Assem that vary the mount position, it's either: by hundreths or thous of an inch due to poor machining tolerances?
-or-
They're made to move it in or out and probably promoted as such, likely pretty loudly promoted too



Reading your two posts, it made me curious if you had the +/- aspect backwards?? I did for years lol.. Finally my buddy was getting wheels for his JL and he straightened me out. I argued, my ego didn't want to be wrong lol... Called him next morn and said: you ere correct, thanks for making me learn it correctly... and that was only about 7-8yrs ago lol

The higher the number the more tucked into the fender the tire will be " + " = further in, under the wheel well. My 18 offset (+18) poke out almost 0.25" more than OE, which was (+)24mm

The lower the number and further negative the number goes " - " = the further outward, as in poke out. example: -44 wheels would stick wayyy out

 

[dkad260]

The CK910 22" wheel has a 24mm offset

My 22" wheel is the CK916 and has a 31MM offset.

Reading your two posts, it made me curious if you had the +/- aspect backwards??

No, my OE CK916 22" has a 31MM offset. The 18" wheel I'm concerned about in the pics has a 26MM offset but is also 1/2" narrower. Cannot see how it sticks out that much farther than the OE while also being narrower. Maybe the tire is slightly wider at the sidewall amd not as straight, but still is poking out quite a bit.

 

[Scrappycrow]

Maybe the tire is slightly wider at the sidewall amd not as straight, but still is poking out quite a bit.

This is a major part of the equation. Knowing the wheel offset and wheel width will only tell you where the inboard and outboard edges of the wheel sit (understanding that the specified width is at the bead -- the actual external dimension is almost always 1" wider at the lip).

What you need to know is the "design section width" (or "measured section width") as stated by the tire manufacturer, which will be for the "design rim width." For example, the Michelin Defender LTX MS/2 in 275/55-20 is specified as 11.2" wide on an 8.5" wheel. If you were to go to a 7.5" wide wheel with the same offset, it might initially seem that means the tire will stick out 1/2" less, but the reduction will probably be only about 1/4", since the measured section width occurs at about halfway between the bead and the tread outer diameter.

So, when you use whatever formula or online calculator to determine how far the outboard section of the tire is, use the tire's measured section width (adjusting for any wheel width changes from the design rim width) in the calculator.

 

[Joseph Garcia]

I'm running 305/50x20 tires on a 20"x8.5"x31mm wheel (OEM stock wheel) on my 07, and the front tire protrudes slightly (1/4"+) beyond the fender. The rear tire does not protrude beyond the fender (because the rear wheels are built slightly closer together than the front wheels for proper tracking purposes). I originally put a 1/4" spacer on the rear wheels to obtain a similar stance as the front wheels, but I later removed them, as good tracking is better than simply balanced looks.

 

[dkad260]

Thanks for the replies. Sadly for me these 18's may be up for sale soon...

Shame as these tires have 8-9/32, total mileage on wheels and tires is about 4K.

In Metro DC area of anyone is interested, if I finalize my decision I'll throw them up in the classifieds. Feel free to PM me.

 

[swathdiver]

Thanks for the replies. Sadly for me these 18's may be up for sale soon...

Maybe this can help. I made this for me, to get a visual on how the different offsets and tire sizes would look in relation to each other.

 

[Charlie207]

What is the reasoning for the concern?

 

[dkad260]

Maybe this can help. I made this for me, to get a visual on how the different offsets and tire sizes would look in relation to each other.

Very cool graphic of the tires, thank you!

What is the reasoning for the concern?

How far they protrude from the front fenders. Honestly it's not a total deal breaker, but for me they just don't look right..and it's a small nitpick.

I had bought these with the notion the 5MM offset would be countered by the 1/2" narrower wheel.

The wheels and tires are in like new condition, and pains me to part with them.

 

[5StarCustmSolutns]

My 22" wheel is the CK916 and has a 31MM offset.





No, my OE CK916 22" has a 31MM offset. The 18" wheel I'm concerned about in the pics has a 26MM offset but is also 1/2" narrower. Cannot see how it sticks out that much farther than the OE while also being narrower. Maybe the tire is slightly wider at the sidewall amd not as straight, but still is poking out quite a bit.

Word..

I went to 35's on an extreme off-road build for mine this spring, and in the process of deciding 10.5 or 12.5 wide? I learned that the measurements are (supposed to be) taken at the widest point and that number on the side of the tire is almost never the widest point measurement of the actual tire.... i.e.- My 10.5's are actually 11.1". The 12.5's Kenda offers in this model are actually 13.3". Every brand I looked was like this....some wider some narrower than the actual number on side of tire