NEW Shoes for RUBICAT : 37x13.50R17 Cooper Discoverer STT Pro M/T Tires

[wayoflife]

Thanks Eddie for the comparisons and comments.

Sounds like so far (with "limited" mileage on the STT's) you'd put the Toyos and STT's above the Nittos and the Toyos seem to still be at the top. Look forward to continuing to follow your thoughts on the STT's as you continue to put miles and trips on them. Thanks again.

Yes. I would still put Toyo MT's on top but only because I've been able to test them out over the long haul. So far, the Cooper Discoverer STT Pros are proving themselves to be an outstanding tire as well and I would argue, hook up better than the Toyos on the rocks. Long term testing will give me a better idea of what I like more.

 

[Jk909]

Yes. I would still put Toyo MT's on top but only because I've been able to test them out over the long haul. So far, the Cooper Discoverer STT Pros are proving themselves to be an outstanding tire as well and I would argue, hook up better than the Toyos on the rocks. Long term testing will give me a better idea of what I like more.

Sorry for the stupid question but aren't toyo and nitto almost the same exact thing? I thought the tread pattern was the same, is the compound of the rubber different?

 

[JAGS]

Okay, compared to Trail Grapplers, the Cooper STT Pros were a bitch to install on our Chamber Pro II's. The bead was just so much thicker and I needed Cindy to help me get the bead seated on the mounting lip. Installing the ring took more effort too and after getting all the bolts tightened to torque spec, there was still a gap between the ring and the wheel. After putting on about a hundred miles, I went back and checked all the bolts and was able to tighten them down more. Everything is now seated more to what I would expect to see and they held up perfect in Moab.

Since I'm not currently running beadlocks, would this be a better or worse situation on standard wheels? You think any concerns popping a bead or anything?

 

[Greg__Berger]

Since I'm not currently running beadlocks, would this be a better or worse situation on standard wheels? You think any concerns popping a bead or anything?

I'n not running mine on beadlocks either, although they are mounted on the stock 7.5" rim. I've had them down to 14 PSI a few times out on the trails and never came anywhere close to worrying about losing a bead. I'm sure the narrow rim plays a big role in that though.

 

[wayoflife]

Sorry for the stupid question but aren't toyo and nitto almost the same exact thing? I thought the tread pattern was the same, is the compound of the rubber different?

Toyo is the parent company of Nitto and so yes, a lot of their tires are the same or at least in certain sizes. For instance, with the exception of tread, a 40x13.50R17 Trail Grappler will have the same rubber compound and internal structure as a Toyo MT in the same size. Likewise, a 40x15.50R20 Mud Grappler will be the same as a Toyo MT in the same size too. Toyo doesn't make a 37x12.50R17 like Nitto does with their Trail Grappler - they only a 37x13.50R17 and only in a load range E. Needless to say, the 37" Trail Grappler is a totally different tire and one that is unique to Nitto. Don't get me wrong, it's still a good tire, I have just found that the 40" version of it is better and not just because it's bigger. Likewise, I am finding that the Cooper STT Pro is a better tire in a 37" size or at least, so far.

 

[wayoflife]

Since I'm not currently running beadlocks, would this be a better or worse situation on standard wheels? You think any concerns popping a bead or anything?

Nope, you shouldn't have any concerns about rolling a bead with these tires on a standard wheel. The issues I pointed out were only in regards to bead lock wheels.

 

[Jk909]

Toyo is the parent company of Nitto and so yes, a lot of their tires are the same or at least in certain sizes. For instance, with the exception of tread, a 40x13.50R17 Trail Grappler will have the same rubber compound and internal structure as a Toyo MT in the same size. Likewise, a 40x15.50R20 Mud Grappler will be the same as a Toyo MT in the same size too. Toyo doesn't make a 37x12.50R17 like Nitto does with their Trail Grappler - they only a 37x13.50R17 and only in a load range E. Needless to say, the 37" Trail Grappler is a totally different tire and one that is unique to Nitto. Don't get me wrong, it's still a good tire, I have just found that the 40" version of it is better and not just because it's bigger. Likewise, I am finding that the Cooper STT Pro is a better tire in a 37" size or at least, so far.

Thanks man. Your insight has helped me save money and make the right decision on more than one occasion [emoji106]

 

[geberhard]

Eddie, any idea if Cooper is planning to release these in 40" flavor?

Thanks, Gui

 

[wayoflife]

Eddie, any idea if Cooper is planning to release these in 40" flavor?

Thanks, Gui

I sure hope so. I'd be getting some for Moby for sure if they do.

 

[JayKay]

Eddie, to answer your "silica compound" question...Cooper has been using this tread compound for a few years in some of their street tires, the Discoverer CTS featured this technology over all other Cooper models. The compound name is based off of "silicon", which is the synthetic material added to the natural rubber in the building process of the tire. There is a trade-off that we've seen in the tire dealer business...the tires with a large amount of silica base perform exceptionally well on wet or snowy road surfaces, but overall mileage is compromised (they tend to wear faster). Cooper actually reduced the mileage rating of the CTS from 70,000 to 65,000 towards the end of their production, because of the issues with most customers getting way less than what the tire was rated at as far as mileage. Cooper has now released the Discoverer SRX in its place, which is a completely redesigned tire.

As far as a daily driver is concerned. Some may wanna look into the Discoverer ST Maxx, same 3-ply sidewall found in the STT Pro, but with a more highway friendly tread design. Now available in a 37/12.50R17

Just trying to give advice on a subject I deal with every day and thanks Eddie for the great first-hand review!!!

 

[JayKay]

One thing to add, I think that Cooper has gotten this "silica" issue figured out with the STT Pro. I believe they added this technology to help their mud tire perform well across the board. Great as an off road tire and great as a daily driven tire. Thats an advantage over most other tires in its class because most M/T tires perform best in one situation...off road.

 

[geberhard]

Jeepkeeper thanks for the insight as well. To Eddie's comment, we have some peeps looking for 40's when are they coming out? Thanks!

 

[JayKay]

Jeepkeeper thanks for the insight as well. To Eddie's comment, we have some peeps looking for 40's when are they coming out? Thanks!

I don't have an answer for that, I don't work for Cooper, just an independent dealer. I'd say with Cooper pushing into the off-road industry, it won't be long until at least the STT Pro will be available in a 40".

 

[WJCO]

They are definitely at the top of my list for my next tire. Hope soon.

 

[OhNoTheJiggies]

Nope, you shouldn't have any concerns about rolling a bead with these tires on a standard wheel. The issues I pointed out were only in regards to bead lock wheels.

Question on the bead topic, since it's my first time installing my own tires onto my beadlocks...
The back bead, does it go over the lip of the wheel on yours, Eddie?
I mounted them and aired up to 35 PSI to see if it would do the audible *pop* onto the bead but it didn't. This is how it looks... Just wondering if yours is the same or if you could post a picture of yours.

 

[geberhard]

Jiggies yours is in the right spot, no it should not go over the rim

 

[OhNoTheJiggies]

Jiggies yours is in the right spot, no it should not go over the rim

Thanks. I wasn't sure if it was supposed to sit over a little like the rim guard thing or whatever it is. But Ive been driving on em for about 800 miles up to Mississippi and all's well. Great tires so far

 

[mastrcruse]

Hey Eddie and others that have been running these tires. How do you like em' still? My overly confident side said I'd DD 40's but I'm growing older (turning 30 soon haha) and thinking 37's will be a good balance for rocks and DDing. Looking at these and wanted to get an update.

 

[wayoflife]

Hey Eddie and others that have been running these tires. How do you like em' still? My overly confident side said I'd DD 40's but I'm growing older (turning 30 soon haha) and thinking 37's will be a good balance for rocks and DDing. Looking at these and wanted to get an update.

Honestly, so far, I really really like them a lot. The real test will be to see how many miles we get out of them but if they hold up, I'll definitely be getting another set in the future. I like these way better than Trail Grapplers.

 

[MedixJK]

I'll definitely be getting another set in the future. I like these way better than Trail Grapplers.

Sooo glad to hear you say this...