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Largest tires on Stock Rebel suspension and wheels

MO Rebel

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Regarding auto recalibration with nav:


I drove past one of those roadside radar signs finally. The displayed speed was within 1 mph of the speedometer, which seems pretty close. However, it was in a 25 zone so I was only going 28 mph at the time (sign showed 29).
The jury is still out on whether the truck recalibrates automatically when you have nav, because the difference from the tires at such a low speed is minimal. I should be traveling 30.5 when the speedometer shows 28, so either the radar was 1 mph above my speedometer, or 1 -2 below my actual speed. That's about as inconclusive as it gets. Has anyone looked into this yet?
I considered going by the radar faster so the difference is great and more evident, but I don't really want the speeding ticket, or to be the a-hole flying through a 25 mph zone. I guess I'll have to keep looking for one set up in a 45 or 55 zone.

Just download this free app. It is spot on in calculating actual speed.
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Shots

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Yeah, that's probably a better choice than flying through a 25 zone, or driving around forever looking for a display posted in a faster zone.
 

Shots

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While recently searching for TSB's on an unrelated item for another thread, I came across one for oversize tire calibration. FCA will charge you $125 to recalibrate the speedometer. → TSB link

Notice they mention that the customer ".... must have their odometers and speedometers calibrated to be compliant with NHTSA odometer reading standards .... "
This would certainly support the prior discussion about the legal requirement to make corrections after adding new tires, that vendors are putting the responsibility on you.

And for $125, I'd buy a programmer instead. It's not much more, and you can do a lot more with it than a one time computer flash.
 

troni

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FWIW, I just installed LT285/75R18 Nitto Terra Grappler G2s on my 2019 Rebel Quad Cab. Had pretty bad rubbing with the front tires during a tight steer. The issue was due to the 1.5 inch spacers I was running when I had the stock tires mounted. Once I removed the spacers, all was well. Well, sort of....once I remove the spacers, the newly placed wheel weights rubbed on the front calipers, so back to the tire shop, I go. Hope this info is helpful to someone. :)
 

Shots

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......Well, sort of....once I remove the spacers, the newly placed wheel weights rubbed on the front calipers, so back to the tire shop, I go. Hope this info is helpful to someone. :)
Yeah, I moved a few of my wheel weights because they were hitting the caliper too. It has nothing to do with the tire, just minimal clearance of the Rebel wheels over the caliper. This could happen with any size tire, depending on how the shop balances them. Probably more likely to happen on a bigger tire though since they tend to need more weights.
 
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JBV

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curious as to further experience with this tire size. in theory, you should have a smoother ride off paved roads, slower acceleration, longer braking, etc. do you notice any of these pros and cons from stock? looks like LT285/75/18 is an uncommon tire size when doing my research....
 

Shots

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The size is a bit uncommon, but the diameter isn't. They're just narrower 35's than normal. A lot of people run 35" tires with typically being 35x12.5 R__. I don't want 12.5" wide tires because they are abysmal in snow/ice, which I realize isn't an issue for everyone. Some people may choose them for other reasons.
A 285 wide tire is between 11" and 11.5" depending on the manufacturer. That makes a noticeable difference in the winter in NE Ohio.

As for braking/acceleration concern., I don't notice any difference. That said, I don't drive aggressively. If you're heavy on the accelerator you may notice a minimal difference. Although I doubt it would be enough to feel, even though you're able to measure it. Likewise, braking* may have a slight measurable difference but I doubt it would be enough to notice without controlled/scientific testing.
* I'm talking threshold braking. Skidding will be identical because the influence of the radius is eliminated because the tire isn't rotating.

Keep in mind, we're talking a fairly minimal tire size change here.

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This is a photo of my OEM Goodyear tire vs my 285/75/18 Cooper tire. OEM size calculates to 33.2" and the Cooper is 34.8". Overall diameter is 1.6" so only a 0.8" difference in the radius. The OEM set weighed 83.2 lbs, while the Coopers weigh 85.9 lbs. So a 2.7 lbs difference.

So yes mathematically speaking, doing controlled tests, performance would probably be measurably different. You've got a little more rotational resistance from weight, with a slightly larger radius. However, it's small enough with this particular change that it will likely be imperceptible without taking measurements.
 
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JBV

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all makes sense. maybe a bit different for me, my vehicle is actually the 1500 with ORG, which is very similar to the Rebel in most ways, but stock tire size was LT275/65/18. i run Sumitomo Encounters at 70 profile. the next size up is your Cooper's. they would fit my truck for sure. thanks for your well informed input.
 

JBV

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do the Cooper's have the mountain snowflake on them? they say it depends on the size on their website.
 

Shots

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do the Cooper's have the mountain snowflake on them? they say it depends on the size on their website.
They've got an "M+S" stamp, but not the 3 peak like the Duratrac had. The treads do have siping so I suspect the reason they didn't get the mountain and snowflake was because the rubber is too hard to meet all the requirements to meet that standard. That's likely why you're seeing the stamp on some but not others of the same tire, depending on size. I wonder if some are made of softer rubber than others. For example, maybe a C or D rated vs an E rated, where both wouldn't be available in all sizes.
 

cnyram

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FWIW, I just installed LT285/75R18 Nitto Terra Grappler G2s on my 2019 Rebel Quad Cab. Had pretty bad rubbing with the front tires during a tight steer. The issue was due to the 1.5 inch spacers I was running when I had the stock tires mounted. Once I removed the spacers, all was well. Well, sort of....once I remove the spacers, the newly placed wheel weights rubbed on the front calipers, so back to the tire shop, I go. Hope this info is helpful to someone.

Is your truck original or have a 2" level in the front? I'm doing the same 285/65R18 but Falken At3'S on oem rebel wheels. I have 1 1/2" spacers right now along with a readylift 2" level and upper control arms with no rub. I'm replacing my level lift with a 3 1/2 lift, but reading as many posts to figure out if no spacers or 1" spacers will rub. I know some have posted using 1/2" or 3/4" spacers but I think 1" are the smallest that come with mounting studs and I don't want to replace the wheel studs if I don't have to. Anyone with a 3 1/2 lift and 285/75R18's, feel free to chime in! Thanks in advance.
 

stancedeuros

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it's posted elsewhere, but for the sake of forum integrity and congruency, I'm running a 295/70/18 just fine on my stock, no air setup. I wheeled it this weekend with no issues. I did remove the tiny 'mudflap' trim piece up front and trimmed off the mounting bracket for it. I'm running 1.5" spacers on the factory wheel set. I run the factory running boards as well with obviously no issues. This pic has them removed as I was attempting to drill 1" lower holes in the mounting brackets to move them up to the cab further. tempImageET1QPa.jpg
 

JBV

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it's posted elsewhere, but for the sake of forum integrity and congruency, I'm running a 295/70/18 just fine on my stock, no air setup. I wheeled it this weekend with no issues. I did remove the tiny 'mudflap' trim piece up front and trimmed off the mounting bracket for it. I'm running 1.5" spacers on the factory wheel set. I run the factory running boards as well with obviously no issues. This pic has them removed as I was attempting to drill 1" lower holes in the mounting brackets to move them up to the cab further. View attachment 147799


just curious as to why you went with 295/70/18 vs 285/75/18 ?
 

cskindt

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just curious as to why you went with 295/70/18 vs 285/75/18 ?
In my mind, I chose the 295/70 for the slight bias towards width rather than height.
The cost and all specs were negligibly different between the two sizes.
Practically, I'm not sure it would make any difference on the road. 📝
 

Rebellion Ram Qatar

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Hi all from Qatar,
I have a 2019 Rebel with factory Air Suspension and have fitted a BFG 35/12.5/18 with minimal rubbing ONLY @ full turn @ lowest ride which practically is not for use except loading and unloading from and to the bed.
 

stancedeuros

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just curious as to why you went with 295/70/18 vs 285/75/18 ?
I wanted width over height. I’m sure the difference would have been fine and I could clear the 285s with ease, just had 295s in stock at my local tire shop.
 

Myersc

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I also went with 285/75/18 tires. I have the Falcon shocks set to level with an additional 1/2 wulf spacer in the front. No rubbing at all. I went with .75" spacers in the front and 1>00" spacers in the rear.
Truck looks great! Can you clarify your front height? Are the Falcon shocks set to level, the same as factory ride height for a Rebel? Then you mention the 1/2" wolf spacer but I don't understand your reference to 3/4" spacer in the front. And did you do 1" in the back? Thanks!
 

NHjake98

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The falcon shocks are set to level but I did not get a complete level out of them, which is disappointing for the money. I put the 1/2" Wulf spacer in the bring it up to where I wanted it which is very close to be level.

The front tires normally stick out 1/4" further from the back from the factory. I don't like that look so I have a 1" Borla spacer in the rear and a 3/4" spacer in the front so the poke is the same front to back.

I really do like the way the falcon shock ride. They are very planted and not too hard. With the Hellwig sway bar in the back and the Falcon shocks all the way around, the tuck rides and handles perfectly.

Hope that helps
 

DieselRebel

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Switched over to TRX Rims with same 285/75 tires and they fit nicely
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