Cooper Discoverer S/T Maxx

T.Low

Expedition Leader
I would trust Consumer Reports even less. They are very biased. Most American cars don't get much of a break. Jeeps in particular are hated. The most revealing thing for me was several years ago when I was contacted by Consumer Report when they were promoting Obama Care. Whatever your opinion is of Obama Care, the fact that Consumer Reports was promoting it and asking me to support it during an election cycle tells me much about their bias.



Damn. There goes that, then. I guess it's just me and God, then, and I'm more than a little shakey with Him at the moment. But that's for a different forum.
 

mikelite80

Adventurer
I just pulled the trigger on these babies! 255/85R16 for my '01 4Runner. My tire guy owes a shop and mostly does work on stupid expensive cars was very impressed with these. He said they were a very well built tire, better then others he'd seen from Cooper. He tells me this as we are standing next to his guys putting tires on a Ferrari, so I tend to trust him about tires. No offense to the guys at Costco just throwing rubber around.

So far they are awesome. WAY quieter then the BFG MT's they replaced. It's been so long but I'd say they are quite as road tires. I'm hoping to get out and get them dirty after the holiday weekend.

If you are on the fence I say go for it!
 

Applejack

Explorer
image.jpg

This weekend I loaded up the 4runner with about 800lbs of people, dog, camping gear and headed out to the high desert where the ST Maxx's would be seeing heavily corrugated roads, sandy and rocky climbs that are challenging because you can't build much momentum. The Cooper's did fine but they did want to dig more than my Duratracs did. I was running street pressure (35 psi) all the way as i had done with the GY's many times before. What I am happy to report is that the numb feeling I was reporting before seems to have subsided. I think for now I will say this, if the Duratracs still offered a 3 ply I would have still purchased them, but I do think these tires will be a pretty darn good all rounder. As I get more testing done I will give a more concise report on my blog and I will post a link.
 

T.Low

Expedition Leader
http://www.coopertire.co.uk/dakar-2013


Somewhere out in the internet "cloud" is Dakar tyre data from the race. Would be entertaining to read an article on how tires are actually chosen by the different teams, how many of what tires were in the race, how many blowouts, racer reviews, etc.

For example, many articles include a sentence about the Minis with tire puncture problems, bit none say wether they were the Michelins or the BFGs. Not that it would necessasarily be indicative in itself of a lame brand or model, but interesting to read (and read between the lines), anyway.

It's the internet, the info is out there somewhere...
 

mvbeggs

Adventurer
STMAXX in 37x12.50R17

Just replaced my Toyo Open Country M/T's in 37X13.50R17LT with Cooper STMAXX's in 37x12.50R17's. I'll let you know how they work out.

Initially, it appears gas mileage has improved. The Jeep's handling feels to be the same as well. (compared to the Coopers, the sidewalls on the Toyos are pretty heavy and stiff)
 

zzz150

Adventurer
i ran cooper st maxx 285/70/17 on a 2 inch lifted regular cab 4x4 f150 on a cross canada northern routes trip that was just around 21000km and was very happy with them, did get a flat but whatever i ran over was sharp, sliced through a tread block into the belts. will get these tires again on my upcoming heep 2dr in a 255. with about 35000km total on them on a small full size that has seen probably 5000km of gravel and other off road driving they are in good condition.
 

kojackJKU

Autism Family Travellers!
yeah, They last forever. I wish they would make a D range with softer side walls, I would run them again. Its just that they are tooooooo damn stiff for the JK. I may run them on my F250 when I get the lift and stance fixed up on it. 2wd, stock, low, boring. I wont be using it off road much but want an eye catcher for work.
 

1stDeuce

Explorer
(I apologize... this got out of hand. If you're not interested in tire construction and load rating, don't bother to read...)

I keep hearing many wishes for LR "D" instead "E". I hate to say it, but I don't think that's going to help.

The construction of my (nearly 8 year old) LR D 285 STT's is on the same 6-ply (3-ply sidewall "Armor Tech") carcass that the LR E 285 ST Maxx's have, and also the same as the current STT's, which are now E rated! The rating used to follow the actual number of ply's in the sidewall, and C tires were 4, D were 6, and E were 8. Obviously, more plys meant a stiffer sidewall. That's just not the case much anymore,
or at least with the Coopers.

The D vs E rating really only sets the max PSI of the tire at rated weight, and for tires with a heavy carcass anyway, is really more about the certification process than construction. My STT's are D rated for 3303 lbs at 65psi, while new STT's are E rated for 3704 at 80psi. I'm fairly confident that they made NO modifications to the tire itself, but rather just re-certified at the higher pressure.

In the past, customers wanted the weight carrying capability, and thus the larger tires were certified as D because there was plenty of carrying capability even at the lower pressure given the larger size. Lately, and due largely to TPMS in trucks requiring the tires to be at 80psi regardless of load capacity, customers are asking for the OE rating (E) when they buy oversize tires. While this provides weight capacity FAR in excess of the dinky OE E rated tires, it allows them to run 80PSI, which keeps the TPMS lights out. Therefore the 6-ply tires that might have formerly been classed as a D tire are now certified as an E. In most cases, and certainly with Coopers, it's the same tire!!

Make sense? What you really want is a 4-ply LR C tire, but the ST Maxx doesn't come as a 4-ply tire, since they use the same 6-ply "Armor Tech" carcass for all versions... In the case of the STMaxx, C just means it was certified at a lower PSI and load... It's still 6-ply, and therefore probably not "softer" at all. If you want a softer tire, you'll have to get one that doesn't have 6-ply construction.

With correction to pressure for the size of tire, I couldn't really tell much difference between a 4-ply 265 LR C goodyear AT/S and my 6-ply 285 LR D STT's in terms of ride quality. I ran 28 in the D's vs. 30 in the C's, which felt the same to me...)

I think the weight of the tire may have some effect on ride, particularly on washboard surfaces, but again, if pressure is adjusted accordingly, there shouldn't be that much of a difference. The sidewall construction has VERY little to do with the spring rate of the tire at normal pressures.

I feel for those of you with TPMS that must put the factory recommended door pressure in... Your ride quality is suffering, but not because of the load range rating, rather due to the large tire really needing less pressure to carry the same weight.

Just some things to consider.
Chris
 
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Fargo

Adventurer
...
I keep hearing many wishes for LR "D" instead "E". I hate to say it, but I don't think that's going to help.

The construction of my (nearly 8 year old) LR D 285 STT's is on the same 6-ply (3-ply sidewall "Armor Tech") carcass that the LR E 285 ST Maxx's have, and also the same as the current STT's, which are now E rated! ...

...My STT's are D rated for 3303 lbs at 60psi, while new STT's are E rated for 3704 at 80psi. I'm fairly confident that they made NO modifications to the tire itself, but rather just re-certified at the higher pressure.

....
Chris

I also have the STT in a load range D and have wondered about this. Did you ever contact Cooper or do any research to verify if they are the same tire or not? Or is this just a hunch?

I would be most interested in hearing how the ride is between the two tires from someone who has run both the Load Range D STT and the Load Range E STMAXX on the same vehicle in the same size tire.
 

Hilldweller

SE Expedition Society
http://expeditionportal.com/field-tested-cooper-st-maxx/

Finished my first review of the 255/80R17 S/T MAXX treads, and providing the link above for those that might be interested but don't visit The Portal's main page.
Thanks; keep us posted.
I have over 16K miles on my 255/80-17s and still admire their all-around performance.
They are getting louder though. Sound like STTs almost now. Doesn't bother me a bit but it's worth noting.
 

Redline

Likes to Drive and Ride
Thanks; keep us posted.
I have over 16K miles on my 255/80-17s and still admire their all-around performance.
They are getting louder though. Sound like STTs almost now. Doesn't bother me a bit but it's worth noting.

Yep, as you know, many traction tires get louder as they wear... But as loud as the STT, wow!? ;)

I removed a set of ******** Cepek Mud Country treads with over 10k from the 4Runner to mount the S/T MAXX. The Mud Country were/are quiet for a mud-terrian, and I still like them, louder now than when new. But in recent years I've really tried to stay with tires similar to the S/T MAXX (******** Cepek FCII, Fun Country, etc), or less than a full-on mud for less noise and better, even wear.
 

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