That idiot is smarter than you think - what he said is true.

6.5 +41 are stock Z85 wheels. You can confirm by the manufacturer sticker on the driver side door jamb (for the width) However, your factory wheel may only be 6" wide if you have the steel wheels. You can pull your wheels and look for a stamping on the inside for the offset. My 2008 Z85 wheels are stamped +41.

Factory backspace is 5.2". The wheel spec you listed is 5.4" (tucked in 1/4" more than stock). However the wheel is 2-inches wider therefore it will poke a lot. That 2" difference in width has to go someplace....right?

The stock tire is probably P225/75-15. that is pretty appropriate for a 6.5" wheel...if you look at a tire of your choice in an 18" wheel you can cross reference what width wheel is approved by the tire manufacturer. Because of the larger wheel and shorter sidewall (removing 3" of rubber), you might be able to get a slightly more narrow tire than 265 to fit on an 8.5" wheel.

Go ahead and call me an idiot if you wish.

 

Yeah I punched it in on the calculator and came up with pushing it 37mm out. they are 15" aluminum wheels that are on it, and they say 23mm.

Now the question is whether to go with a:

18x8 +35

or

20x8.5 +35

Planning to do 3/4 drop in the future. What is recommended?

 

Unfortunately I am useless for lowering....

The +23 factory offset sounds suspicious. Again, useless for that too then.

I can only assist with tire/wheel sizing for stock and lifting.

 

20x8.5 +35 with a 255/35/20 should be fine on stock suspension, correct?

 

I am running 20x9 with +25 offset and they still tuck if you are looking for that look. Also on 255/35/20 tire

Before I was running a 20x9.5 with a +35 offset and it stuck out about 1.5 inches. I hope this helps



With a 3/4 drop, you will have a lot of gap on a Z85

 

I wonder if the +23 is a 2wd offset wheel. My truck is 4x4.

Assuming stock tire is 225/75-15, the 255/35-20 is about 1.25" shorter than stock.

According to the calculator, an 8.5" wheel at +35 gives a backspace of 6.1" which I believe is too far tucked and will rub with a 255 tire. I know that twill not work on a 4x4.

 

Looks like a lot of people are running that setup judging by the lowered wheel chart, I went ahead and ordered wheels and tires

 

The lowered wheel/tire chart is definitely going to be your best bet on what will/won't work, just make sure you're paying attention to the mods listed for the size you want.

And imo, 20's on these trucks lowered look great. Make sure to post pics!

 

A lot of gap where? Are you saying a z85 needs more than a 3/4 drop?

 

This is a 5/6 drop on 20x9 with 255/35/20 tire

 

Looks good, not sure I'm ready to go that low yet though

 

It's not that bad, as long as you have a low pro cross member

 

AND a C-Notch

 

I have a stock 2005 z85 ls I want 18x9 wheels which offset should I get?

 

Well this kind of leaves alot of options without all the info. What size tire will you be running and what look are you going for? tucking the wheels or more of an offroad look?

 

Im kind of wanting to go with an offroad look maybe later down the line when I have the funds and yes its 2wd im not necessarily wanting a low profile tire. Would you suggest I go 18x8

 

What size tire do you think you want to go with?
An example is your stock tire size is 225/75-15 (28.3").
If you went up to a 235/55-18 you would get nearly the same size (28.2). I don't know if that size is available, but you can tell how the sidewall being reduced gives you the overall height.

What you need to do is check the tire web sites (a tire that you are considering to use) for the size you want to go with and see what they recommend for wheel size. Perhaps a 235/55-18 has a recommendation of 9" wide wheels.
They all vary a little bit.

The various tire manufacturers have a chart with the recommendations listed on their web pages.

 

Mounted my wheels today, drop will be here Christmas eve. Here's a pic.

 

That's a 20x8.5 on the 255/35 falken 722

 

Details please.
What backspace did you end up with? How close is it to rubbing, or how much rub does it have, if so?
And pics from front the front or rear to show these guys the stance?

 

Wheels are kmc spider, 6.13 backspace, no rub at all anywhere, tons of room all around!

 

Nice job. Glad it worked out for you.

 

I have an 07' GMC Canyon SL 2wd on some old 205/75r15 and want to slap on some new tires. Kind of looking for a more aggressive look. Will some 31/10.5r15 fit on the stock rims and tuck under the truck without a lift or trim? If so I'm looking at General Grabber AT 2.

 

Check your manufacturer door sticker (driver side door jamb). I think your factory wheels are 6" wide. That is too narrorw for a 10.5" tire.
A 31" usually fills up the fenders of a 4x4 Z85 truck (similar to yours but taller). So I doubt you will get 31's to fit.

Are the tires you listed stock size? If you are unsure, the stock size is also listed on the manufacturer sticker.

Assuming they are stock, A 31" tire is 15" larger (which is very significant) and won't fit.

I can't remember the stock tire for an 07 2wd but I think your tires are undersized. Please confirm. Even if your stock is 225/75-15, I think 31's are too tall.

 

Yeah they are 6". What would you recommend? Maybe 30/9.5r15? I'm a noob so you'll have to excuse my ignorance. Might have to bite the bullet and get some new wheels.

 

Stock tire size please?

265mm is 10.4" wide.

I'm afraid the size that will fit your truck is going to be a little disappointing.

 

205/75r15 is stock size.

 

I might guess that a 235/75-15 is about as big as you want to go.

Sounds almost like you have a W/T model with the steel wheels.

The tire I listed is almost 2" taller (6.5%) than your stock tire (1.8") and over an inch wider (235mm-205mm=30mm)
That is also the stock tire size on a Z85 4x4 of the same model year.

If you are lucky a 245/75-15 might stuff under the fenders. You will need to check the tire manufacturers site for a tire you're after to see if that size is available, and to see if a 245mm tire is recommended for a 6" wheel.

 

Word, thanks for the very useful information.