LT 285/65/18 Cooper Discoverer STT pro all terrain

[Drome]

Yes more on tires I know. I'm currently running LT 275/65/18 BFG k02s. I'm not real happy with the ride and road noise. I ditched my air ride after way to many problems and to much money spent. I put in the heavy duty Oldman EMU coil spring conversion with the 2 in lift.
I am extremely happy with the results. I'm not one who rock crawls or any heavy fourwheeling. Moderate trails and a little advanced trails for me. Moab was a breeze for the new coils on the moderate trails. Good clearance, no rubbing... I was expecting some. I will admit that I miss the automatic leveling.
A little about my LR3,
2006 SE.
Non locking
155000 miles.
Recent work,
New maf
New plugs
BG 44 flush
Replaced lower steering shafts
Two sets of off road lights
Nerf bars rather than running boards
The engine is running very strong.
So back to the tires. I really want to try a 285/65/18 Cooper discover sst pro. It looks like it has enough clearance. I checked with cooper and they said they will be OK on my 8 in rim width. I want a quieter tire with good off road capabilities. I've read good things on this tire. I'm just wondering on if I will now get some rubbing. I can live with some off road rubbing during heavy articulation, but nothing else. Any one have any experience with this tire or tire size?

 

[Houm_WA]

You sure about that size? I run those tires in a 275/65R18....not 285. Maybe check that.

Anyway mine are 32.6. if your 285 Is not a typo you're gonna rub for sure. Also....my Coops are LOUD.

Oh....and it's DiscoverER Pro not DiscoverY.

 

[m_lars]

You sure about that size? I run those tires in a 275/65R18....not 285. Maybe check that.

Anyway mine are 32.6. if your 285 Is not a typo you're gonna rub for sure. Also....my Coops are LOUD.

Oh....and it's DiscoverER Pro not DiscoverY.

Are you sure your 275/65 are 32.6 and not 32.1?

I’ve got the cooper s/t maxx in 265/70/18 which measure (theoretically) 32.6” compared to the nearly identical 32.58” of a 285/65/18

I had minor rubbing backing up at full right lock with about 1” of GapTool lift with BOTH my 265/70/18 s/t maxx AND 275/65/18 Duratracs. I was able to remedy that with a grinder and a flappy disc in no time flat. I did additionally get a rub in the rear wheel wells at the pinch seam when I went to the taller coopers, which I have since flattened.

Houm_WA says those his pros are loud, I would call my s/t maxx noticeable, but far from loud. They are definitely not as aggressive as the pros, but I am very impressed with their performance in dirt, and snow if that matters.

 

[Houm_WA]

The 32.6 is based off of Cooper's specs. I haven't measured or anything. They are louder than my MT/Rs and that's really the only basis of comparison I have. I think it's to be expected if you're buying a tire with open tread.

 

[m_lars]

The 32.6 is based off of Cooper's specs. I haven't measured or anything. They are louder than my MT/Rs and that's really the only basis of comparison I have. I think it's to be expected if you're buying a tire with open tread.

Ha! I didn't even think to check the specs on their website, I've always just done the math based on the size listed. All three of the sizes discussed here run larger than the theoretical size listed on the sidewall.

LT275/65R18 123\120Q E RWL 32.28" (calculates to 32.07")
LT285/65R18 125\122Q E RWL 32.91" (calculates to 32.58")

LT265/70R18 124\121Q E BLK 32.87" (calculates to 32.61")

Regardless of the minute details, I would think he's ok based on what I have experienced with my slightly different tires from the same manufacturer. They're obviously wider, but nearly identical diameter. I don't think they'd rub rear (after flattening the pinch seam and moulding the inner fender) and I think you could adjust the front wheel well IF necessary.

Agreed on the open tread remark, I wouldn't expect them to be quiet based on how the tread looks. I actually looked at them and decided to go less aggressive due to my commute.

 

[Houm_WA]

What about the frame horn in the front? mine is an '05 and the horn is a non-issue. I still think ball joint can be tricky, too.

If I had to run one set of tires I'd make a different choice. I switch between those and my Nokians.

 

[jwest]

285/65 is not the best choice for the factory 8” wheels. The guy above w 265/70 has the best size because they provide max height while fitting the best during turning as well tucking into fenders at full compression.

285/65 is a lot wider than the 265/70 and without the full spectrum of physical mods, they’ll run like hell in several places.

While it gets mentioned that 1” ‘lift’ via IIDtool helped, it doesn’t change anything whatsoever in the full function and clearance of these tires. The strut will move and that 1” becomes irrelevant.

The only true ‘lift’ is to use the strut spacer which actually limits the fully tucked position where rubbing can occur. It’s kind of like having the HD steel spring kit on as far as the ride height and tire position.

 

[zelatore]

I don't log in here often but I saw this pop up in the weekly thread email.

Here's the simple answer - it won't fit without constant rubbing.

I'm running the Cooper SST-Pro in 275-70-18 on stock wheels. I've done all the usual cutting and trimming and run Johonson Rods.

The real worry is the upper A-arm knuckle. With my 275 I have only the smallest bit of clearance. About 1/8" inch. In fact, I touch at certain degrees of articulation when the truck flexes out (if you can use that word with these trucks....) I've never actually felt it touch but I've taken the paint off the knuckle.

You're wanting to run a 285 - 10mm wider than I have and I'm already touching here. That won't work unless you run spacers. BUT - if you do that it will cause all sorts of other problems because it increases the swing radius when you turn the front tires. I have a set of 1/2" spacers I used to run with smaller tires - I've tried them with these and no-go. It causes the tire to badly rub the front of my sliders when turning and that's not something I can cut as it provides a lot of the strength to the slider (Tactical Rovers) and we all know how much these trucks use the sliders in the rocks!.

I've heard some people say they run a 285 tire, but usually it's just an AT and not a more aggressive MT like the STT/Pro. The STT/Pro has a fairly large sidewall lug compared to more moderate tires which is what leads to the contact with the knuckle.

As for the tire itself, I like it but don't usually recommend it for the LR3/4. Honestly these trucks aren't great for tougher trails - if you want to do that you'll be SO much better off with a solid axle rig. Given that, I think the best fit for these based on mission is a more aggressive AT tire like the Cooper ST/Maxx, the Goodyear Duratrac, or the KO2

 

[zelatore]

(edit)
I see from the pictures you're not running rock sliders - in fact, it looks like you have running boards (!). That tells me you are not looking to do much more than fire roads. That's fine - it's what these trucks are best at. With that in mind, I really don't think you'll be happy with a full MT tire. It's going to be louder, more expensive, and get worse gas mileage. Again, I would recommend staying with something in the AT world.

 

[Drome]

I've been delayed by a medical emergency with my wife. It may be a few weeks now. But it will give me a chance to post some pics of the clearances I have currently. I get them done tonight after I get back from Denver.