Cooper Discoverer S/T Maxx

[Redline]

Thanks for the feedback, any experience with the ST MAXX in the snow? I actually ordered the AT3's on Friday but just saw the 255/80 ST MAXX and am thinking about changing my order.

Nope, not enough to remember or talk about. I got my set late last winter, a very dry winter here. Hoping to get some snow and ice time with them this coming year, but I'm confident they will be will be good enough for my uses in the Sierra Nevada. Probably not as good as a more heavily-siped design, but all designs are a trade-off. I'm very happy Cooper is making this tire in the 255/85 & 255/80 sizes.

 

[jpat30]

They performed great on their maiden voyage! On-road and off-road manners are grippy and predictable, although with this talk of the "right side pull," I am getting that even with two alignments. It's not that bad in the Xterra as some others' vehicles, but I'll be rotating this week to see if anything changes.




Sure thing. Anything specifically you need measured? I'll chalk up some quick measurements/pictures for you tomorrow (overall height/width and contact patch).

Overall height is most what I am interested in but contact patch would be great too. Thanks Richard

 

[richard310]

Overall height is most what I am interested in but contact patch would be great too. Thanks Richard

I took some pictures yesterday but I'm not at home to upload them. The OD actually measures out to 32" on my spare (stated on the website as well) but with about 40psi and the weight of the truck, it's actually 31." The contact patch is about 9" with a 10" overall width unweighted.

 

[Applejack]

I got to test mine out in the snow yesterday. It wasn't a deep snow test by any means, 3-4 inches at most but it was the first chance I got to see how they would perform in the white stuff. They are not great when the snow is packed. They tracked fine in fresh snow but just about any tire with a decent amount of tread will do that when there is only 4 inches. I always take tires to the same test locations so that I have some kind of a baseline. Not exactly scientific mind you, but just some good old "real world" testing. On the packed snowy road to our local ski resort I got the chance to try and push them a bit, throttling and trying to drift corners a bit. The STM's don't like to be pushed. Where my old Duratracs felt really composed and confident, the ST MAXX is quite vague feeling, making difficult to determine where the traction threshold is especially in terms of lateral grip. Where the Duratrac's felt more like a purposed snow tire, the ST MAXX offers nothing beyond what one might expect from an average all terrain. The tables may turn when the snow gets deep but, I have yet to find deep snow yet, and I have very serious doubts these tires will outshine the DT's, but I will give them a fair shot to be sure. So far they are a little disappointing in every area I have tested them, especially since so many people have praised them so highly, it really got my expectations up.

 

[kojackJKU]

My thoughts too. They worked.....But rode like a brick, wandered over the roads and had an inherent right hand pull no matter of wheel alignment, tire rotation, even swapped wheels in the tires. Still pulled to the right all the time. The BFG I have now are a much better overall tire.

 

[1stDeuce]

I've been in snow a few times and been more than happy. This weekend i ran some icy trail in 2wd that would have had me sliding around on the old worn STT's, but I think any decent all terrain would have been just as good. Maxx's are not really "winter" tires by my judgement, as they don't have nearly enough siping to be great performers, but they seem very much adequate for the things I do with my Jeep. And when it comes to chewing through and keeping me moving, they are downright impressive!! I dug my way up this really steep climb on Imogene the other day, and it just kept going. In the end, it was easier to put two tires in the dirt on the scary edge and crawl up, but it was impressive that they just kept pulling out in the snow with a bit of wheel spin.


And this was this weekend up La Plata Canyon. No problem once I aired down a bit from the 31psi that I normally run. 2wd on packed snow/icy trail getting here was no big deal until it got steep, and then 4wd fixed it. I was able to make first tracks, but once it got too steep, I couldn't climb while pushing snow with the axles. My lite little Jeep on 255/85's at 15psi did about as well as the 80 series on 35" MTR's at 10psi.



Hmm, that picture makes it look like 6" of snow, but I was dragging both axles, so I'd say 15+" by the time I turned around.

If you want an on-road ice and snow tire, you might want to consider a more winter friendly design, like the AT3 or whatever that new tire is. Or the new BFG AT from what I hear. But if you want a heavier lugged tire that'll do almost everything well, the STMaxx seems to do it all!

BTW, If you really are worried about ice, it's also studdable if you happen to live out west... A studded mud tire will kick the snot of of any non-studded A/T out there once the roads get icy.

 

[kojackJKU]

I've been in snow a few times and been more than happy. This weekend i ran some icy trail in 2wd that would have had me sliding around on the old worn STT's, but I think any decent all terrain would have been just as good. Maxx's are not really "winter" tires by my judgement, as they don't have nearly enough siping to be great performers, but they seem very much adequate for the things I do with my Jeep. And when it comes to chewing through and keeping me moving, they are downright impressive!! I dug my way up this really steep climb on Imogene the other day, and it just kept going. In the end, it was easier to put two tires in the dirt on the scary edge and crawl up, but it was impressive that they just kept pulling out in the snow with a bit of wheel spin.
View attachment 256679

And this was this weekend up La Plata Canyon. No problem once I aired down a bit from the 31psi that I normally run. 2wd on packed snow/icy trail getting here was no big deal until it got steep, and then 4wd fixed it. I was able to make first tracks, but once it got too steep, I couldn't climb while pushing snow with the axles. My lite little Jeep on 255/85's at 15psi did about as well as the 80 series on 35" MTR's at 10psi.

View attachment 256680

Hmm, that picture makes it look like 6" of snow, but I was dragging both axles, so I'd say 15+" by the time I turned around.

If you want an on-road ice and snow tire, you might want to consider a more winter friendly design, like the AT3 or whatever that new tire is. Or the new BFG AT from what I hear. But if you want a heavier lugged tire that'll do almost everything well, the STMaxx seems to do it all!

BTW, If you really are worried about ice, it's also studdable if you happen to live out west... A studded mud tire will kick the snot of of any non-studded A/T out there once the roads get icy.

I beg to differ, a studded MT tire is down right dangerous on icy roads. the studs do nothing. I had at set of hankook MT studded on my F150 and that loved to try to loop out on me on icy roads. If the AT has more siping it will grip better. But arguing which NON winter tire is better for winter is like arguing which light is better for the daytime. I run full winter tires studded and you have a night and day difference in traction.

We just got out first taste of winter this week, and I still have my BFG AT's on. While they are ok, for everything other than soup mud, they are not that great in snow/ice. I need to get my W/Ts spooned on this week.

 

[1stDeuce]

?? On ice, your studded tires were not good?? It's possible they put the studs in too deep I suppose, but they really should have been much better than a non-studded all season... KojakJKU, you just keep getting the shaft with everything you do...

 

[kojackJKU]

Nope they were done right. Just there is no siping in a MT tread to flex and form with the ice to create more surface area and therefore more grip. Simple physics. MT are made for mud, not snow. not ice, hell not every driving on pavement a lot.

 

[Hilldweller]

I used to use MTs on ice all the time. Just fine.

...with chains.... :sombrero:

 

[kojackJKU]

Ha ha I just use tires made for winter. They work great. I think chains are overkill. No one here runs them.

 

[Mad_Texan]

Anyone have the 255/80/17 on a full size? I see most pictures online of these on mid-size trucks (tacoma, etc) or on the rear of duallys but not any on a full size. Too narrow? Trying to decide between the 285/70/17 Cooper AT3's or the 255/80/17 ST MAXX for my 2013 F150 SuperCrew Heavy Duty, both are 32.8" tall. Stockers are 245/70/17 BFG Rugged Trail which are anything but rugged.

I have mine on a full size... I'm pretty happy with them so far!

 

[Omar Brannstrom]

Hi

Iam not an expert but correct me if Iam wrong.

I have got the impressions that a dedicated winter tyre is best for plowed roads but for unplowed roads with deep snow it aints so good then a tyre like S/T Maxx would be better with bigger lugs in deep snow.

 

[kojackJKU]

I am not sure on that omar, I think the winter tires compound and design trumps any other tire unless maybe a mud tire aired way down. that might do it. I know that on the polar expedition vehicles they use swampers aired down to like 10 psi on beadlocks. But that's not conditions I see when driving in the winter.

 

[Hilldweller]

Real snow tires are designed to pick up snow, hold it in the tread/siping, and use it to adhere itself to the next snow it encounters. Sorta the opposite of mud tires that do their job best when they clear their voids of mud on each revolution.

My Toyo AT-2 Xtremes worked quite well in snow, both virgin or left-over. My Cooper STTs didn't work so great on the packed stuff but were okay on deep virgin stuff. My MTR/Ks were okay on the fluffy stuff but not so good on packed.
Old MTRs and other unsiped MTs I ran were scary on almost any snow without chains.

We used the chains on an old Power Wagon on NJ highways to pull cars out of ditches in bad weather. That truck was a riot.