285/75/17 vs 285/70/17?

[lmturne1]

I currently have a set of Nitto Trail Grapplers installed and am due for a new set within the month. They are on the black TRD T4R wheels and I am contemplating upsizing to 285/75/17 in the same tire. I will attach the specs of the two different sizes below.

Has anyone had a set installed, and if so what suspension setup, wheels (offset), and spacers (if any) do you have installed as well?

Did you encounter any issues at full turn or flex?

My rig is outfitted with an ICON stage 3 kit with the billet adjustable UCA's and no spacers.

In the image provided, the top and bottom lines are the specs in question. Disregard the middle line.

 

[salong53]

I'd just go outside, turn my wheels to full lock in both directions, and measure to see if you'll have clearance for the added radius of the tires. If you have 0.47" to spare, you'll be fine. I doubt you'll have that much room though.

(34.09" - 33.15" = 0.94" divided by 2 equals a 0.47" increase in radius)

 

[Titanpat57]

or search...

there's only 4,639 tire size threads...I guess one more doesn't matter..

 

[wfo9]

You can get them to fit. Most people run them with 17x8 - 10 offset (4.1BS).
It still requires some trimming.. and a body mount chop. Probably also need to relocate the washer bottle like I did. Caster also needs to be maxed out...

I'm running 305 70 MTRs, which is about the same at 34.1" diameter.

I flex my truck out all the way often.. And I only get a very faint rub here and there. Nothing I can even hear really, but I can see slight evidence under careful inspection.

I would also highly recommend a re-gear to run this size tire. You will really be pushing the limits on stock gearing.

I plan to go up to a 315 next, but will also probably add a 1/4 body lift to help clear a little more tire.

 

[Kodiak555]

They fit! That's my exact setup. I put the wheel/tire on without the coilover so I could run the suspension through full articulation. My setup fits with zero rubbing. I am not running spacers. I tried to, but they rubbed when I tested the full articulation. I'm not sure about the BMC, since I performed it prior to my lift install.

 

[lmturne1]

The consensus after performing a simple search and finding multiple threads addressing my initial question is that a multitude of smaller mods have to be completed prior to installation.

1) BMC, castor adjustment, & possible fender lining trimming
2) Increased (2") bumpstops in the rear
3) Possible regear, depending on how much weight you've added to your rig.


After the addition of the rear bumper in a few weeks, and a front bumper in a couple months I can confidently say that I will have crossed that threshold. So the ends, in my case, won't justify the means.

285/70/17 are here to stay..... at least for the next 35K miles...

 

[gmatherly]

The consensus after performing a simple search and finding multiple threads addressing my initial question is that a multitude of smaller mods have to be completed prior to installation.

1) BMC, castor adjustment, & possible fender lining trimming
2) Increased (2") bumpstops in the rear
3) Possible regear, depending on how much weight you've added to your rig.


After the addition of the rear bumper in a few weeks, and a front bumper in a couple months I can confidently say that I will have crossed that threshold. So the ends, in my case, won't justify the means.

285/70/17 are here to stay..... at least for the next 35K miles...

I have a similar setup (285/70/17 nitto ridge grapplers on scs Ray 10s and a 3" toytec lift) and I CAN NOT get the rubbing to stop. I'm a few weeks away from the BMC which I have no problems with but today the black plastic behind the front passenger side tire popped off when I drove through a ditch.

I feel like nobody else here is having the issues I'm having so what am I doing wrong!?

 

[Jhalko]

I have a similar setup (285/70/17 nitto ridge grapplers on scs Ray 10s and a 3" toytec lift) and I CAN NOT get the rubbing to stop. I'm a few weeks away from the BMC which I have no problems with but today the black plastic behind the front passenger side tire popped off when I drove through a ditch.

I feel like nobody else here is having the issues I'm having so what am I doing wrong!?

Is it the wheels? I mean usually it’s spacers or some odd backspacing for the wheels from most posts. I assume you have high caster and did the fender liner mod as well right?

 

[gmatherly]

Is it the wheels? I mean usually it’s spacers or some odd backspacing for the wheels from most posts. I assume you have high caster and did the fender liner mod as well right?

I guess it could be the wheels but so many people use the scs wheels on here, that I'd assume the issue would be documented more. I have a pelfrybilt bumper so the front of the tires do t have any rubbing issues. Caster is maxed out at 4 degrees and I'm prepping for the BMC.

Even with the BMC, it won't address the issue of popping that black piece of plastic off of fender.

 

[codyHTX]

285/70 BFG KO2 on 17x7 (~50% tread) vs 285/75 BFG KO2 on 17x8.5

BFG and their whack sizing. spec'd to be taller, but looks wider / larger tread blocks. haven't tried to measure anything yet, I'll update over the weekend

edit:
measured both wheel/tire combos off the vehicle
285/70: 31.5" (with about 0.5" tread worn)
285/75: 33"

i thought the 75's were wider but both measured 9" across the tread. i think its an optical illusion due to a 1.5" wider wheel (better suited for 285) and the tread blocks themselves being physically bigger to accommodate the larger circumference

 

[Decipher]

^Excited to see this come together!

33s look right (285/70) but damn does that 285/75 look mean. What a difference!


Sent from my iPhone using Tapatalk

 

[Jetboy]

FWIW - I have 285/75/17 Cooper AT3s.

Body mount chop was required. Not really even close to fitting without. Lift makes no difference in tire fit in the front, so height doesn't matter. But I have about 2.5" lift (adjustable Fox suspension). Alignment and UCA matter. I have JBA UCAs and alignment set to about 4*. They still rub on the front bumper lip at full lock in reverse a little bit. Otherwise. After a mild BMC there's plenty of clearance at the body mount/fender area.

What stood out most in the Cooper version as compared to a Toyo AT2 was that the 75 was both taller but also significantly narrower tread. They're even narrower than my street tire set, which are 275/65/20 - by almost an inch at the tread.

Mine are on stock wheels. I have some custom 1" spacers that I use. I machined the back side of my OEM wheels for space for the studs. This is getting into a bit more custom machining that you should not DIY unless you have some experience machining aluminum.

 

[Spanky4R]

FWIW - I have 285/75/17 Cooper AT3s.

Body mount chop was required. Not really even close to fitting without. Lift makes no difference in tire fit in the front, so height doesn't matter. But I have about 2.5" lift (adjustable Fox suspension). Alignment and UCA matter. I have JBA UCAs and alignment set to about 4*. They still rub on the front bumper lip at full lock in reverse a little bit. Otherwise. After a mild BMC there's plenty of clearance at the body mount/fender area.

What stood out most in the Cooper version as compared to a Toyo AT2 was that the 75 was both taller but also significantly narrower tread. They're even narrower than my street tire set, which are 275/65/20 - by almost an inch at the tread.

Mine are on stock wheels. I have some custom 1" spacers that I use. I machined the back side of my OEM wheels for space for the studs. This is getting into a bit more custom machining that you should not DIY unless you have some experience machining aluminum.

Question about your 285/75's. When stuffed & front wheel turned how close are u to the fender, not the well but actual outside edge of it & did you lengthen the front bumpstops? I'm about to order some 285/75 Falkens & just wanna make sure I'm all good.

 

[rochmpr]

Question about your 285/75's. When stuffed & front wheel turned how close are u to the fender, not the well but actual outside edge of it & did you lengthen the front bumpstops? I'm about to order some 285/75 Falkens & just wanna make sure I'm all good.

When I was running 285/75 Toyo MT's, the lugs would catch some of the fender screws that hold the fender flares on on the inside of the upper portion of the wheel well. It was not bad, but you could hear it and see wear marks. Since stepping up to 315/70's, I have trimmed out about an inch from the entire fender and flare and now do not have any rubbing. This is with stock bump stops and referencing the front only. In the rear, I have never had any rubbing issues with either size tire.

 

[Spanky4R]

Ok, that helps. If it's that close just a washer or two may keep it outta there. They're gonna be AT3W's measured at 33.86

 

[WEAK_E90]

285/70 BFG KO2 on 17x7 (~50% tread) vs 285/75 BFG KO2 on 17x8.5

BFG and their whack sizing. spec'd to be taller, but looks wider / larger tread blocks. haven't tried to measure anything yet, I'll update over the weekend

edit:
measured both wheel/tire combos off the vehicle
285/70: 31.5" (with about 0.5" tread worn)
285/75: 33"

i thought the 75's were wider but both measured 9" across the tread. i think its an optical illusion due to a 1.5" wider wheel (better suited for 285) and the tread blocks themselves being physically bigger to accommodate the larger circumference

pics on the car Cody?

 

[Jetboy]

Question about your 285/75's. When stuffed & front wheel turned how close are u to the fender, not the well but actual outside edge of it & did you lengthen the front bumpstops? I'm about to order some 285/75 Falkens & just wanna make sure I'm all good.

It's close - but does not rub anywhere at full stuff at any steering angle. The only minor rub I get is on the front bumper cover in reverse at full steering lock. I looked for a pic at full stuff. You can see it's close - but it doesn't ever touch. I have just the regular OEM bump stops.

(Not sure who the guy in taking video is. I assume he was with our group in some way, but I didn't see him around amp and I've never seen any video. Maybe he was with someone else on the trail?)

This video kinda shows how close it gets. It stuffs really nicely into the fender well without rubbing.
<iframe width="1280" height="720" src="https://www.youtube.com/embed/sWkJPQZPIfc" frameborder="0" allow="accelerometer; autoplay; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>

 

[666HailSanta]

Recently put 285/75's Wildpeak's on my truck and regret not doing it sooner.

I'm running a 3/2 lift with -10 offset wheels and SPC uppers running 4 degrees of caster - running a 2inch extended bump stop in the rear and Wheeler's bump stops up front.

Couple of things worth noting:

- Had to re-do my BMC to get a lil' more aggressive with it, but not a big deal.
- Trimmed the front lip of the bumper to prevent rubbing in reverse
- Bent in the pinch weld
- Removed my valence caps (will trim them eventually), no rub when driving on the street but it gets real weird when flexing out.

But that was it. No rub from what I could tell (or saw/heard). I loved having the extra tire and it was super grippy at 15PSI.

It performs about the same as 285/70's in terms of gas mileage and being geared like garbage (so slow). I've got a set of 4.56's on the way to fix it though!

 

[canadian bum]

It's close - but does not rub anywhere at full stuff at any steering angle. The only minor rub I get is on the front bumper cover in reverse at full steering lock. I looked for a pic at full stuff. You can see it's close - but it doesn't ever touch. I have just the regular OEM bump stops.

(Not sure who the guy in taking video is. I assume he was with our group in some way, but I didn't see him around amp and I've never seen any video. Maybe he was with someone else on the trail?)

Quick hijack. But what are you running for rear bumper protection? Custom?

Also I'm running 285/75R17 Ridge Grapplers and still have the front mud flaps on and no BMC. Stock Rims, Stock Upper control arms. Can see where the rubber takes the paint off the front of the upper control arms but that's minor. And then when bottoming out the front suspension can see where it rubs a little on the plastic fender liner all along the top. It's pretty much perfect fit.

 

[Terra Firma]

285/70 BFG KO2 on 17x7 (~50% tread) vs 285/75 BFG KO2 on 17x8.5

BFG and their whack sizing. spec'd to be taller, but looks wider / larger tread blocks. haven't tried to measure anything yet, I'll update over the weekend

edit:
measured both wheel/tire combos off the vehicle
285/70: 31.5" (with about 0.5" tread worn)
285/75: 33"

i thought the 75's were wider but both measured 9" across the tread. i think its an optical illusion due to a 1.5" wider wheel (better suited for 285) and the tread blocks themselves being physically bigger to accommodate the larger circumference

This is the exact combo I am looking to move to (SCS and 285/75/17 ko2). Hows the ride and mpg delta from the smaller ko2's?

Thanks!