35" Cooper Discoverer STT Pro on Stock 2015 Ram 2500?

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ngiovas

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I know there are lots of threads on tire fitment, but I wanted to ask about my specific application before I pull the trigger.

I have a 2015 Ram 2500 CC long bed 4x4 that I bought used earlier this year. It came with stock 18" wheels and brand new Hercules Trail Digger M/T tires (275/70R18) which the Hercules web site says are 33.4"x11" diameter. My original plan was to run the Hercules until they wear out, but they are the worst tire I have ever driven on. I have had multiple instances where I was braking on wet pavement at moderate speed and the truck slid. Yesterday we had a dusting of snow and I had to put the truck into 4x4 to back into my driveway because the tires would spin no matter how lightly I hit the accelerator. The road noise is horrible, but I could tolerate that if the tires were decent.

With all of that said, I want to move up to a 35" tire if possible, but I would like to avoid putting a lift kit or leveling kit on if possible. I am looking at the Cooper Discoverer STT Pro 305/70R18. The Cooper site says that they are 35"x12.4". Will these tires rub, or can I get away with them? If there is very slight rubbing, can I put a wheel spacer on? If so, what are the downsides of doing so and what should I look for?

As a side note, this is not my daily driver. I mostly use it for towing and hauling. I drive it an average of 2-3 times a month. I mostly tow on the highway, but I need to be able to drive through snow (i'm in Michigan), wet roads and some rocky/muddy remote roads.

As I mentioned, I wasn't planning to buy tires this soon, but I need to do something before the snow gets deeper as I don't think these tires are safe.

Thanks in advance,
Nick

***EDIT***

Looking at the price of the leveling kits, that may be an option depending on the negatives of installing the kit. Plus, now that the temps have dropped, I would likely have to pay someone to install it for me instead of freezing my hands off :).
 
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Ratket

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Someone has done it I am
Sure, they will chime in shortly.
 

Nick@GotExhaust

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You can fit 35x12.5 tires on stock wheels with slight rub on the radius arms.
 
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Phil21502

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If u want look at a 295/70r18. It's between stock size and 35's. About a 34x12.00 I have these and had zero rub with stock wheels and stock suspension. Added a leveler for looks and didn't do a track bar and then the passenger side rubbed the radius arm slightly.
 

loveracing1988

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I run the mastercraft courser mxt's (a distant relative of the cooper's) in a 315/70r17 on power wagon wheels and have zero rubbing. From what I understand those wheels have a little more offset than stock though. If driving on snow is any concern of yours though find a good all terrain. My tires were about the same as the crappy stock Firestone tires in the snow new and now that they are halfway worn they are garbage, like you I had to use 4wd to get into my driveway yesterday.

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ngiovas

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I run the mastercraft courser mxt's (a distant relative of the cooper's) in a 315/70r17 on power wagon wheels and have zero rubbing. From what I understand those wheels have a little more offset than stock though. If driving on snow is any concern of yours though find a good all terrain. My tires were about the same as the crappy stock Firestone tires in the snow new and now that they are halfway worn they are garbage, like you I had to use 4wd to get into my driveway yesterday.

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loveracing, looks like you are also in Clarkston, so you were dealing with the exact same snow as me :).

I'm starting to lean towards the leveling kit now. I have been digging through some old posts and it sounds like it may not be as bad as I thought it would be. I also watched a couple of videos and the install looks much more straight forward than I thought it would be. The biggest challenge would be dealing with the cold weather.
 

loveracing1988

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loveracing, looks like you are also in Clarkston, so you were dealing with the exact same snow as me :).

I'm starting to lean towards the leveling kit now. I have been digging through some old posts and it sounds like it may not be as bad as I thought it would be. I also watched a couple of videos and the install looks much more straight forward than I thought it would be. The biggest challenge would be dealing with the cold weather.

Lol, small world. I've wanted a simple 1 inch level since I bought my truck, I don't want to go any higher for when I decide to haul something. It just hasn't ever been at the top of my to do list.

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U&A

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For what its worth, i have toyo Open County M/T’s in a 285/75/18. True tire measurment is a 35.1x11.6x18.

No rubbing.

That size is limited on tires but its an AWESOME size
 

theviking

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I'm running Cooper S/T Maxx 35x12.5 on the factory 20" rims with a 1.5" level and absolutely nothing rubs. I was considering the STT Pro's as well but the Maxx series seemed like a better option for on-road and winter use.
 
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ngiovas

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I'm running Cooper S/T Maxx 35x12.5 on the factory 20" rims with a 1.5" level and absolutely nothing rubs. I was considering the STT Pro's as well but the Maxx series seemed like a better option for on-road and winter use.

I will check out the Maxx tires as well.
 

Megazor

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I've been running 295/60r20 STT Pros on my 14 stock Megacab for about a year. Just noticed today that I have been slightly rubbing the front control arms. Just enough rubbing after 10k miles to see the shine come off the paint. In the driveway turning lock to lock they don't touch so they must only be rubbing at max turn on uneven ground/bumps. I've been rotating them every 2500 miles with no issues.
 

Will Ram 2500

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Here is mine with 305/70/18 on tradesman stockers. I do have a 2 inch level spacer with shock relocation bracket. I just get rubbing on the radius arms at full lock both ways because of the positive wheel offset...not a big deal. These trucks look so much better leveled if you can swing that. I have 26k on these tires now. I'm hoping for 40k, but I don't know if they'll go that long. Haven't had lots of snow in KC for a few years, but the small one we got last year with ice under it, they were excellent.20160923_164633.jpg 20160923_164750.jpg
 
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