15x8 vs 17x9 wheels? Tire availability, price and load ratings?

Rickyd

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Hey guys I'm looking at getting rid of the crappy 15x10 steel wheels on my jeep for some aluminum mammoth boulder's in either 15x8/3.75" backspace or 17x9/4.75" backspace.

Possibly going from 33x12.5 to 33x10.5. But not set in stone.

I like the 285/70-17 tire. Lots of choices and imbetween the two widths above. But limited availability in load range c? Another downside to this is the 4.75" backspacing possibly creating clearance issues inboard.especially with a taller tire like the 35x10.5/17 in the future?

I know what the good ol 15x8 entails. I just have zero experience with the world of 17" tires. Any advise? Experience to share?

Thanks
 
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I made the mistake of going with 16 x 6 inch wheels . Very few tires to choose from for a 6 inch wide wheel , especially 33 inch tires .
Luckily , Falken came out with a 255/85r16 that is C rated and works well on my narrow wheels . For years I ran a 235/85r16 and was happy with it even though it was E rated . When I decided to go taller , selection was rather limited . 16 x 7 wheels would have made it easier .
 
which one is lighter? is my go too for making decisions, If you’re looking for a tie breaker on wheel & tire decisions:
 
I wouldn't entertain 17s unless I was for sure using 35" tires.

But 4.75" backspacing is perfect for 33x10.5s.

There's a lot of controversy on load ratings. I've only had C on my Jeeps but if D and E really ride much worse then 17s make the selection pretty thin. It also makes the tires more expensive, which I understood in 2002 but now because in 2024 they have to be making far more 17s than 15s. They cost what the market will bear, I guess.
 
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Hey guys I'm looking at getting rid of the crappy 15x10 steel wheels on my jeep for some aluminum mammoth boulder's in either 15x8/3.75" backspace or 17x9/4.75" backspace.

Possibly going from 33x12.5 to 33x10.5. But not set in stone.

I like the 285/70-17 tire. Lots of choices and imbetween the two widths above. But limited availability in load range c? Another downside to this is the 4.75" backspacing possibly creating clearance issues inboard.especially with a taller tire like the 35x10.5/17 in the future?

I know what the good ol 15x8 entails. I just have zero experience with the world of 17" tires. Any advise? Experience to share?

Thanks

For a 33” tire I’d stay with a 15” wheel.

For a 35” tire I’d go with a 17” wheel.

The weight difference in the wheel will be negligible. Weights of tires can vary widely.

Load doesn’t matter as much as I thought. My 35x12.5r17’s are Load D and I can’t tell much of a difference with my 35x12.5r15’s Load C’s onroad. I have switched back and forth regularly lately.

For backspace, 3.75”. You could make the 17x9” Mammoths with 4.75” bs work with a 1” spacer. However, running a 10.5” wide tire on a 9” wide rim wouldn’t be desirable for me.
 
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I like 15's on a TJ. There aren't a lot of wheel choices in a 17". Many end up using TJ to JK adapters, which I'm not a fan of unless there's a real need to do so. Though a 17" will give you more room for brakes.

Custom 17" are an option. That way you can order the BS and bolt pattern you want.
 
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I'm in the same situation as you (15x10" wheels). I'm going with the 15x8" charcoal Mammoth Boulder wheels when money permits. I had them with 33s on my old Sahara.
JEEP6 (2017_11_20 00_38_12 UTC) (3).jpg

My inspiration.
Mammoth boulder wheels (2).jpeg
 
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I'm in the same situation as you (15x10" wheels). I'm going with the 15x8" charcoal Mammoth Boulder wheels when money permits. I had them with 33s on my old Sahara.
View attachment 548877
My inspiration.
View attachment 548881
That is probably what I'll wind up doing. Top it off with a 33x10.5 km2 if i feel like skinnys

i do like the idea of the 285/70/17 size.11.2" wide But the big wheel will more than likely look odd.
 
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That is probably what I'll wind up doing. Top it off with a 33x10.5 km2 if i feel like skinnys

i do like the idea of the 285/70/17 size.11.2" wide But the big wheel will more than likely look odd.

I don't think they look odd. Maybe I'm just used to it, but I've had plenty of 33's on a 17" wheel. 285/70R17 on both my jeep and my colorado

1723050380751.png


1723050537457.png
 
I will be making a similar decision as well, except I'm already running a 15 X 8 wheel with 33 X 10.50 KO2's. I'm leaning heavy towards 17's. 285/70R17 Toyo Open Country R/T Trails in a C load on Mammoth 17's. I don't see 15" tires getting any cheaper or having more sizes available in the future.
 
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I don't think they look odd. Maybe I'm just used to it, but I've had plenty of 33's on a 17" wheel. 285/70R17 on both my jeep and my colorado

View attachment 548892

View attachment 548894

From what i read,285/70-17 is imbetween a 12.5 and 10.5 in width and a little taller than a "33". But floatation sizes almost never measure true.

What is your experience comparing them?
 
I hated my 17" wheels with 33s. Maybe it was because the wheels were ugly. :unsure: I bought it that way and changed them soon after.
SAHARA 03 1 (2017_11_20 00_38_12 UTC).jpg

jeep s 1 (2017_11_20 00_38_12 UTC).jpg
 
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I'm with Boog on this one. I think 17s / 33s looks off (cringy even). 17s / 35s is better. If you're playing on more than service roads and need to air down to low double or single digits, more sidewall = more better. 15/33 or 15/35. Just my 2 cents.
 
These are 15x8 with the 3.75 offset with 33x10.5 K02s. I’m partial of course but like the look with plenty of sidewall. The 3.75 offset with the 10.5s have worked well. There’s no poke outside the fenders (but right on the edge) and has made my life easy since there’s less interference issues with the offset plus more narrow tire. Combo did better than I could have hoped off road as well and with the wheels being relatively inexpensive, I don’t mind all the new rock rash!


IMG_6473.jpeg
 
I have the 17x9 Mammoth Boulders and love them. There is plenty of sidewall with a 33" tire and 17" wheel. Anyone who tells you different hasn't seen or used 17's with 33's off road. I can get these down to 16 PSI without any issues. When these tires need replacing, I will be going to a 35 and adding a 1" body lift.

The only thing I'd do differently, is go with the gun metal gray color. The only reason is for a little break from the black. I may still yet order a set and have them made into beadlocks.

17" wheels give you the option of either standard or metric tire sizes.

20240415_155756.jpg


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