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Discussion Starter #41
Sorry to bring math into this discussion...

Stock XT wheel: 18X7 +48 Offset
This makes the backspace:

A 7" rim is 178mm wide, midline at 89mm from the back of the rim.
89mm + 48mm = 137mm

An 8" rim is 203mm wide, midline at 102mm from the back of the rim.
137mm - 102mm = 35mm to get the same backspace as stock.

Initially, it looks like you are correct, if you only consider where the back of the rim lines up compared to stock. Once you consider how the tire plays into it though, that offset is not what you think it is:


Let's start by looking at the stock wheel and tire combo:

(225/55/18 +48 offset)
113mm (1/2 section width) + 48mm (offset) = 161mm (tire backspace) = This is the distance from the hub surface to the inner face of the tire, and determines if it clears the suspension components. Let's use this as our benchmark for comparison.

My tire combo (235/65/18 +48 offset)
118mm + 48mm = 166mm = 5mm closer to the suspension components.

GeoJosh's tire combo (235/65/17 +40 offset)
118mm + 40mm = 158mm = 3mm further from the suspension components compared to stock. So you actually have MORE clearance on the suspension than stock. However, you also push the outer face of the tire 13mm out further, which makes it more likely to rub at full lock.

With a 35mm offset and 235mm wide tires:
118mm + 35mm = 153mm = 8mm further from the suspension components compared to stock. This also means you have 82mm of "frontspacing" (distance from the hub surface to the outer face of the tire) vs 64mm with the stock offset. This means you are pushing the outer face of the tire 18mm further out than stock.

Now, none of this takes into account the differences between mounting a 235mm tire on a 7" rim vs an 8" rim (the skinnier rim will "pinch" the tire more, and should be effectively a taller tire, but effectively skinnier compared to the 8" rim.)

I think this is the biggest thing Rim and Tire guys forget about backspacing when they are looking at offsets and wheel width. The wheel backspace still matters as far as clearing steering knuckles and tie rods, etc, but the tire backspace is what matters for clearing the strut and spring perch.
 

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New Year soon, once my dedicated 17" 225 60 Nokian WR SUV 3 winters (on old 17 WRX wheels) are off my '14 XT in the Spring, I'll be starting to look at new Tyres for the OEM 18" XT wheels.

As 95% of my driving is twisty engaging Countryside/Mountain Scottish B-Roads with a v small amount of soft offroad tracks and campsites, at the moment I'm leaning towards Continental Cross Contact UHP in a size of 235 55 18 as a good compromise between performance and comfort.

However that said, I do like the look of the GO15 and the fact you could possibly use them well into the shoulder seasons either side of winter, I did notice that they do the more summer orientated GO12 in the stock size of 18 225 55 in the UK, as I seem to remember GeoJosh mentioning most of his driving is onroad with the ATS (=GO12??), so I have to ask how are the GO15s in 18 235 60 on the road, particularly cornering and spirited driving, do they feel secure & responsive?

Thanks in advance... and HNY folks.... :)
 

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Discussion Starter #43
I do feel like the G015's are a little closer to "on the edge" of traction than other tires I've tried in dry weather spirited driving. Full impending lock-up braking for example, I can get the tires to break loose earlier than a more street oriented tire (thus reducing my braking distance) however, still better than the stock Dueler HL 400s. Cornering is tough for me to compare though, since the '17 has active torque vectoring, it turns better than the '15 I had, and I've only had the G015's on the '17. I still feel like they get to the edge of traction sooner than a street all-season.
This is usually the trade off for an all terrain tire though, so I am ok with it.
 

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YES!- The new Geolander AT/015 in 225/65/R17 fit 2017 Foresters.

Hello, All. My first post in here in a VERY long time. I just picked up a 2017 Forester 2.5i HFA. So far I have 400 miles on it and it's everything I expected from Subaru. My last Scubie was a '06 XT/manual. I miss that car...but I digress. I pulled off the stock tires and put on 225/65/17 Geolandar AT/G015's. They fit PERFECTLY! NO rubbing at full lock. The steering feels much more connected to the road with these tires. The road/surface noise is no different then the stock 91's. Maybe a tad bouncier, but it's what I expect from an AT tire. I am very glad I made the changeover to these tires.

Here are some pictures to illustrate.
 

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YES!- The new Geolander AT/015 in 225/65/R17 fit 2017 Foresters.

Hello, All. My first post in here in a VERY long time. I just picked up a 2017 Forester 2.5i HFA. So far I have 400 miles on it and it's everything I expected from Subaru. My last Scubie was a '06 XT/manual. I miss that car...but I digress. I pulled off the stock tires and put on 225/65/17 Geolandar AT/G015's. They fit PERFECTLY! NO rubbing at full lock. The steering feels much more connected to the road with these tires. The road/surface noise is no different then the stock 91's. Maybe a tad bouncier, but it's what I expect from an AT tire. I am very glad I made the changeover to these tires.

Here are some pictures to illustrate.
Thank you so much for posting your impressions, I was expecting this for a long time...

I'll probably do the same in my 17', only things that scares me is warranty, computer/diff problems due to change of dimensions and homologation problems (I live in Spain and any changes done to the car must pass an inspection, paying, of course).

Please, keep posting your impressions in snow, mud...

Thanks!
 

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I have gone with 16" steel wheels for GO15 215/70/16 so I can switch between the normal wheels with Primacy 3's on when I want or don't need ATs for a period of time. The diameter on these is only 5mm larger than the stock 225/60/17. I have only used them on the road so far and they feel good, no more noise and no change in ride quality.
 

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Hello All,

I mounted Geolandar G015's 225/65R17 on my 2015 FXT. I downsized my rims by purchasing a set of old FRS/BRZ wheels 17x7 48mm offset, 20 lbs. My question is, what PSI are you guys running these tires? I'll try to find out the optimal PSI for these things, but I'm wondering if anyone has already figured this out.
 

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Got these on this weekend from @Discount Tire, went with a 235/65/17 on method rally's that are a 38mm offset. Overall couldn't be any happier. They fill out the wheel well perfect without a lift, barely rub in the front, not enough to have any concern, and are actually quieter then the stockers! I had the Geolander A/TS on my Silverado and evne with a beefier tread they lasted forever, were quiet, and rode great. made it an easy decision to go with the G015's.


 

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monkeyracer, I have this tire in 225/65/R17 on my '15. I've got a few weeks and 1500 miles on them but no rain yet. I lost a few MPG over the stock tire and the ride is not quite as smooth but it's only noticeable when I think about it. I'm not a fan of the loss of highway handling (100 mile daily commute) but the gravel, dirt, field, and rock handling is superior. Since those are the roads I live around and enjoy exploring I'm happy with the switch. The worst road they've seen so far is made of fist-sized rocks and mud but they brought me through fine. I'll admit that I did chicken out on day 1 when I tried a mud road but felt a slip just a car length in. When I've got someone with me to help dig it out I'll find that one again.

From the pics I can't be sure but I think the 17 has more "armor" on the side wall.



I think the 10mm less width in the 225 saves the tire from rubbing at full turn but only barely.
Hey man, nice tires. I have a quick question because I just mounted these on some aftermarket wheels and when I hit dips I?m getting a scrape in the rear. Have you felt this at all? Thanks!
 

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Hi there!

I got a pinch blowout on my Duellers and I'm having such a hard time deciding on new tires.

Monkey, how is the rubbing? Is it really noticeable? Or just occasional?

Also, am I much better.off just going g the 17 route?

I can't really drive my car.much on the Donut so I really need to.get this figured out!

I'm about to just buy these geolanders I just don't want to regret it.

If you get on it, do they perform? Or do you lose traction?

Sent from my Nexus 6P using Tapatalk
 

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Hey man, nice tires. I have a quick question because I just mounted these on some aftermarket wheels and when I hit dips I?m getting a scrape in the rear. Have you felt this at all? Thanks!

I would have replied sooner but I've been away for a while. In the beginning the rear tires were SO close to the wheel well and I think I did feel that with dips but it didn't seem to affect anything.

Now to update my long-term review: I am on my second set now. I had to replace 2 of them after one got a metal object lodged in the sidewall. Then original pair began to lose some of its sipes along the outer edge somewhere around 20,000 miles of wear so I replaced those. Now I have about another 26,000 (and a bit of gravel every day) on the newer pair and they are losing the same set of shallow sipes around the outer edges. They don't drive like new but they do have still have fine tread depth so I don't plan to replace them yet.

We had ice for a couple days this past winter and a couple inches of snow. The tires handled fine up and down these small Texoma hills.

Would I buy them again? Well, I don't know how I feel about those same sipes disappearing so quick but they do have the handling I expected of them.
 

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It appears that Yokohama has a new size for the Geolander A/T G015: 225/55-18 has anyone put this on a 14+ XT with the OEM wheels?

I would love to know how they look and perform on the car. I had been planning a 17" wheel purchase next spring but I have not seen this tire size before. Is is a super duper new size? or did I miss this size when previously searching and get excited looking at new rims...
 

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I wish I could see these pics! I want to run 235/60/18 on my 2018 Forester Black Edition with a 1" lift and 20mm spacers! I am worried about the rubbing though.
 
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