STMAXX or KM2 - Another 255/85R16 thread

Fargo

Adventurer
Currently I have Cooper STTs in a 285/75R16. They have been great tires, but they are now at about half life so I am hoping I can get $125-$150 each for them and buy a new set of tires. So that puts me in the market to try out a 255/85R16.

I'll be honest and admit that most of my driving is on the road. I live in ND and the only time I really get offroad (other than a prairie trial on occasion) is when we take a vacation in MT or CO every couple of years. So I really need a tire that is reliable on the highway to make those trips. My STTs have been great. The noise has been pretty minimal and the little siping they have has been enough through the rain and even the snow in most cases.

The reality is that the STMAXX is probably a better tread design for my needs. They are also a little shorter than the KM2s so they might fit a little better. Although I am setup for the 285s so I don't think that is a big issue.

The KM2 of course are more aggressive and look better. I also understand that BFG has software sidewalls and I wonder if it might ride better with the KM2s. I do have some concerns that the KM2s have no siping and could be terrible in the winter and bad in rain. But I expect I could sipe them.

So the way I see it, the STMaxx has a quieter tread advantage and possibly better wet weather. The BFGs might have a ride advantage but I expect will be noisier. The KM2 is also taller to give more clearance and aggresive tires just look better. They could also be siped if winter driving becomes an issue.

Now here is the crazy part. From checking with local pricing, I can actually get the KM2s about $20 cheaper per tire ($250v$230) than the Coopers. Of course once I add siping to the price, they are about a wash in pricing.

So what are your thoughts and recommendations. Anyone had both STT and KM2s or STMAXX to compare to my current tires.
 

Kylsix

Bad Mofracki
Me and two buddies each got different tires (all on 2012/2013 Tacomas). One got Duratracs, one got KM2s, and I got the S/T Maxx (in 255/85-16), so I have pretty decent first hand experience with each tire.

I'll start with the S/T Maxx since I have the most experience with them. Road noise is incredibly negligible. Everyone who rides in my truck makes the same comment about how quiet they are when cruising down the highway. They are absolutely awesome on dirt roads and snow, and have had no noticeable trouble with them at all in varying terrain. I've gone every bit as far in deep snow, sand, mud, etc. as my buddies with the different tires. Now, the 255/85-16s are E-rated and have a particular puncture resistance that makes the sidewalls pretty stiff. Depending on the size of your vehicle, this might not be ideal. I got used to it, but some people complain about the stiff ride (OME suspension doesn't help with that either).

The KM2s are pretty damned comparable to the S/T Maxx tires, and if they came in the size I wanted I probably would have picked them up. They have performed equally well in every bit of terrain as the S/T Maxx tires and Duratracs, but ride a little better on surface streets as they are a softer tire. They are a bit louder than the S/T Maxx. However, what is gained in comfort is lost in puncture resistance, so you really need to decide how important that is to you.

I'd stay away from Duratracs for sure, though. I'd recommend the S/T Maxx for any real overlanding/off-roading, but the KM2s might be a little better for a daily vehicle.
 

1stDeuce

Explorer
I don't drink the BFG koolaid, but I can give you some Cooper-aide if you like. :)

I switched my jeep from 285 STT's to 255/85 ST Maxx's. I couldn't be happier. It drives noticeably better than it did with the 285's, and snow/wet traction is quite a bit better. They're still not great on ice, but short of a winter tire, not much does well there... They are definitely quieter than the STT's, and in my Jeep, I can't actually hear them at all unless I air down on pavement, and even then its not much. By comparison, the "New Fun Country" tires on my truck are LOUD.

At the same pressure, the E Maxx's ride better than the D STT's I took off. (I run 30 all around on the road, and air down to 15 offroad unless it's sandy.)
I think the KM2 tread compound is OK, but it's going to wear out faster. If ice is a concern, siping will help either tire tremendously.

If you can find a good deal on 17" wheels, the 255/80R17 Maxx's are quite a bit cheaper than 255/85R16's, and there's still plenty of sidewall. I've got 17's on my truck, and planning to put 255 Maxx's on it when the 265 Cepek's wear out. (Hoping the Maxx's have a rebate this summer...)

As for looks, I like the Maxx sidewall. It's not gawdy, but it looks at least as "aggressive" as the KM2's IMO.
Chris
 
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Fargo

Adventurer
Now, the 255/85-16s are E-rated and have a particular puncture resistance that makes the sidewalls pretty stiff. Depending on the size of your vehicle, this might not be ideal. I got used to it, but some people complain about the stiff ride (OME suspension doesn't help with that either).

The KM2s are pretty damned comparable to the S/T Maxx tires, and if they came in the size I wanted I probably would have picked them up. They have performed equally well in every bit of terrain as the S/T Maxx tires and Duratracs, but ride a little better on surface streets as they are a softer tire. They are a bit louder than the S/T Maxx. However, what is gained in comfort is lost in puncture resistance, so you really need to decide how important that is to you.

I'd stay away from Duratracs for sure, though. I'd recommend the S/T Maxx for any real overlanding/off-roading, but the KM2s might be a little better for a daily vehicle.

Did you and your buddies all get 255/85R16s? Size could make some minor differences. But this is a great comparison. Thanks.

I'm surprised to hear you say the KM2s are so similar to the STMAXX. I expected them to be a lot louder and scary on wet roads or winter roads. The softer sidewall of the KM2s would be nice since they are going on a Jeep LJ. I think I could deal with the weaker sidewalls for the offroading I do. Noise may not be too much of an issue in the end. The Jeep does have some wind noise. But it would be nice to make it a bit quieter.

You really surprised me at the end saying the KM2s would be better than the MAXX for daily driving. I would have thought the STMAXX would be the better daily driver. Do you like the KM2s better due to the sidewalls?

What is it about the duratracs you don't like. If they made them in a 255/85 I would have purchased them without even looking at others.
 

Fargo

Adventurer
I switched my jeep from 285 STT's to 255/85 ST Maxx's. I couldn't be happier. It drives noticeably better than it did with the 285's, and snow/wet traction is quite a bit better. They're still not great on ice, but short of a winter tire, not much does well there... They are definitely quieter than the STT's, and in my Jeep, I can't actually hear them at all unless I air down on pavement, and even then its not much. By comparison, the "New Fun Country" tires on my truck are LOUD.

At the same pressure, the E Maxx's ride better than the D STT's I took off. (I run 30 all around on the road, and air down to 15 offroad unless it's sandy.)
I think the KM2 tread compound is OK, but it's going to wear out faster. If ice is a concern, siping will help either tire tremendously.

If you can find a good deal on 17" wheels, the 255/80R17 Maxx's are quite a bit cheaper than 255/85R16's, and there's still plenty of sidewall. I've got 17's on my truck, and planning to put 255 Maxx's on it when the 265 Cepek's wear out. (Hoping the Maxx's have a rebate this summer...)

As for looks, I like the Maxx sidewall. It's not gawdy, but it looks at least as "aggressive" as the KM2's IMO.
Chris

This is great info too since I currently have the same size STTs and looking to move to the same size MAXX on my Wrangler. I'm very glad to hear the Maxx rides better than the D range STTs. I've never complained about my STTS but I had concerns about moving to a load range E.

Interesting to hear your thoughts on the new fun countrys too. I also have considered the new Extreme Countrys. But if the fun countrys are that loud then I guess I don't need to look at the Extremes.

It was also interesting the hear the KM2s have softer rubber. If I siped the KM2s, do you think the KM2s would be a better winter tire than the ST MAXX?
 

1stDeuce

Explorer
It was also interesting the hear the KM2s have softer rubber. If I siped the KM2s, do you think the KM2s would be a better winter tire than the ST MAXX?

I doubt the rubber is softer, but there's definitely less of it. (Some say land vs. sea, the Maxx's have more land and less sea, the KM2 are mud tires, with more sea than land.) Totally a guess, but a siped KM2 would probably do about as well wet/snow as a Maxx. A siped Maxx would probably be better still.

IMO, the KM2's are "old technology". The new BFG A/T's are supposed to be about the best non-winter tire out there in snow and ice, but the KM2's are still on old tech rubber, and IME, they're a bit slick in the rain and snow. Maxx's have a more modern rubber compound, so that helps with traction. It's not all about the tread pattern anymore, with some of the crazy rubber compounds they've developed.
 

Fargo

Adventurer
I doubt the rubber is softer, but there's definitely less of it. (Some say land vs. sea, the Maxx's have more land and less sea, the KM2 are mud tires, with more sea than land.) Totally a guess, but a siped KM2 would probably do about as well wet/snow as a Maxx. A siped Maxx would probably be better still.

IMO, the KM2's are "old technology". The new BFG A/T's are supposed to be about the best non-winter tire out there in snow and ice, but the KM2's are still on old tech rubber, and IME, they're a bit slick in the rain and snow. Maxx's have a more modern rubber compound, so that helps with traction. It's not all about the tread pattern anymore, with some of the crazy rubber compounds they've developed.

I didn't remember that the KM2 was that much older than the STMAXX. It would be interesting to know more about the rubber compound. I thought the KM2s wore faster due to softer rubber, but it could just be the fact that their is less surface (land) area to wear on that they wear faster. I had thought a siped KM2 would outperform a STMAXX, but as you said I could also sipe the Maxx.

I think the MAXX would probably be a better tire for me. Even though I have STTs, I've often thought of the Cooper tire as being more of a 2nd tier tire and BFG being a 1st tier. But that may not be the case. It seems the STMAXX is often more expensive than the BFG. So maybe the BFG is not as much better of a tire ans I had always thought. Wet traction is very important to me. I may have to pay a little more and go with the less aggressive STMAXX even though I like the looks and appeal of the KM2 better.
 

Mo4130

Adventurer
I had the km2s when my rig wasn't a daily driver out in Washington and they defiantly hum going down the highway. Realistically if most driving is going to be on road don't be that guy that gets mid terrains and drives on the street the time. Get the maxx and be done with it.
 

RubiconGeoff

Adventurer
The ST Maxx is a more well-rounded tire that performs in all terrain types. The KM2 is a mud terrain tire that's fairly street-friendly, but has some serious compromises in the name of mud performance. The ST Maxx is definitely more street-friendly. I am in love with how quiet and smooth my 315/70R17 ST Maxx's are, and they have been wearing very evenly withoutk any of the cupping/feathering that mud terrain tires are known for. The ST Maxx's set the benchmark for puncture resistance, whereas BFG's have not been known for this (although hopefully the new KO2 has addressed this shortcoming). I would personally pay a hefty premium for the ST Maxx's over the KM2's.
 

Fargo

Adventurer
The ST Maxx is a more well-rounded tire that performs in all terrain types. The KM2 is a mud terrain tire that's fairly street-friendly, but has some serious compromises in the name of mud performance. The ST Maxx is definitely more street-friendly. I am in love with how quiet and smooth my 315/70R17 ST Maxx's are, and they have been wearing very evenly withoutk any of the cupping/feathering that mud terrain tires are known for. The ST Maxx's set the benchmark for puncture resistance, whereas BFG's have not been known for this (although hopefully the new KO2 has addressed this shortcoming). I would personally pay a hefty premium for the ST Maxx's over the KM2's.

Nice summary. You address well the reasons I prefer the MAXX to the KM2 and give good insight into the tire. I think the biggest draw to the KM2 is that it is taller and although the sidewalls are believed to be weaker, I think they will give a softer and more compliant ride. Also, BFG is usually thought of as a superior tier 1 tire while Cooper is often considered a tier 2 tire. Although, I'm not sure that is accurate or just a perception based on marketing forces.

Did you have any specific compromises in mind that the KM2 suffers from for the sake of mud? Or just the general noise and wear issues of a mud tire?
 

RubiconGeoff

Adventurer
Did you have any specific compromises in mind that the KM2 suffers from for the sake of mud? Or just the general noise and wear issues of a mud tire?

I'm just referring to the general compromises of a mud-terrain tire versus an all-terrain or a street tire. Bigger tread blocks and bigger voids mean more noise, higher rolling resistance, more uneven wear, reduced traction in rain, snow, and ice, etc.

The ST Maxx has an aggressive all-terrain tread pattern in its center, with mud-terrain shoulder tread blocks. Every tire is a compromise; it's just a matter of finding the right tire for your own particular needs. My Jeep is a daily driver that sees fairly extreme off-road use, so the ST Maxx suits my needs perfectly: it's the most road-friendly aggressive tire on the market. It's not the best at any particular terrain, but it's the best at being the right compromise for me.

I would not call my Load Range D ST Maxx's a rough-riding tire. I felt no difference switching directly from Load Range D BFGoodrich casings to these Load Range D Cooper casings, but you can of course adjust the ride quality by fine-tuning your inflation pressure.

BFG is usually thought of as a superior tier 1 tire while Cooper is often considered a tier 2 tire. Although, I'm not sure that is accurate or just a perception based on marketing forces.

I would also not call Cooper a "tier 2" tire manufacturer. They are one of the world's largest and most technologically advanced tire companies, certainly on the same level as Michelin/BFGoodrich.
 

Robert Bills

Explorer
. . . BFG is usually thought of as a superior tier 1 tire while Cooper is often considered a tier 2 tire. Although, I'm not sure that is accurate or just a perception based on marketing forces. . . .

It is marketing. Michelin/BFG, Goodyear and Bridgestone/Firestone are often referred to as "flagship" tire lines based upon their relationship with auto manufacturers as OEM tire suppliers. Cooper's strategy from the outset was to focus on the lucrative replacement tire market. Cooper has been in the tire business since 1914 and is the 5th largest tire manufacturer in the U.S., 9th worldwide.
 

Mo4130

Adventurer
To break it down. Ones a mud terrain and the other isn't. Which one to you want. A mid terrain or an all terrain.




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Fargo

Adventurer
To break it down. Ones a mud terrain and the other isn't. Which one to you want. A mid terrain or an all terrain.




Sent from my iPhone using Tapatalk

After all my research, it starts to look like it really does break down that simple. Its just like me to not see the forest for the trees.

After all my research I am pretty much decided on the Maxx. In large part for the simple fact that I don't need a mud tire. Now I just need to sell my old tires. Thank you to everyone.
 

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