Sidewall strength, tire pressure, and tire quality

[OSV]

They aren't actually plys or layers of material any more. The MTRs use Kevlar in their side walls. That is strong stuff.

kevlar is manufactured as a fiber, that can be woven into a fabric.

i have an mtr that's got a rip in the sidewall, i can see the ply layer.

"Kevlar is the registered trademark for a para-aramid synthetic fiber, related to other aramids such as Nomex and Technora. Developed by Stephanie Kwolek at DuPont in 1965,[1][2][3] this high-strength material was first commercially used in the early 1970s as a replacement for steel in racing tires. Typically it is spun into ropes or fabric sheets that can be used as such or as an ingredient in composite material components."

"Goodyear gave some of its dealers and members of the media a chance to test out its Wrangler All-Terrain Adventure, made with a DuPont Kevlar aramid belt" http://www.tirebusiness.com/article/20130802/NEWS/130809984/goodyear-unveils-kevlar-belted-wrangler

 

[OSV]

That won't help. The flats happen when the side gets pinched against the metal rim

that entire post is illogical nonsense, lol... if you are pinching the sides of your tires against the rim it's because you are not running enough air pressure, or more likely in your case, running a c-rated tire that has a weak soft sidewall.

you are so paranoid about your weak tire sidewalls that you had to spend $900 on stauns.

this is the perfect example of an e-rated tire that has strong sidewall, that can withstand direct abuse, without the sidewall getting pinched against the rim, yet still deform with the shape of the obstacle, for maximum traction:

 

[Stumpalump]

that entire post is illogical nonsense, lol... if you are pinching the sides of your tires against the rim it's because you are not running enough air pressure, or more likely in your case, running a c-rated tire that has a weak soft sidewall.

you are so paranoid about your weak tire sidewalls that you had to spend $900 on stauns.

this is the perfect example of an e-rated tire that has strong sidewall, that can withstand direct abuse, without the sidewall getting pinched against the rim, yet still deform with the shape of the obstacle, for maximum traction:

View attachment 355789

That picture is not of a tire forming with the shape of the obstical. It's a direct hit. He backed up and used his lead foot like you were told by others in this thread. A C would wrap on its own without the novice lead foot. I'm paranoid because I run Stauns you say. I run the best of everthing. C tire BFG Krawler and the best beadlock. The Stauns or now Coyote holds both beads. It supports the 6 psi side enough that I can still drive at 50. I can run flat if I pop half way up a dangerouse climb. I cut virgin trails on soft un compacted mountains at the Superlift off-road park and Robilios off road park in New Mexico. I'll probably go to the NRA headquarters soon because they want to cut trails for off roading on their 30000 acre home base. Beadlocks are not paranoid, but more professional grade stuff. I love internal air beadlocks and would pay a grand a piece for them. Next best thing to a 12v fridge.
For sake of conversation let's say an E has a stronger sidewall. A D8 dozer has steel tracks but we don't use them because they beat you to death. They ride ruff, they don't flex, they are heavy, they cost more, they beat your body, they beat up and break more mechanical stuff, they don't track as true, they bounce, the rubber is too hard on the tread causing wheel spin and chunking, the belts under the tread are too stiff to conform to baseball size rocks, the side is too stiff so they flop left and right, they take more air and time to air up, they are the wrong tire. I own two sets of E. One is a KM2. They perform worse off road in every category. They do nothing better but some suggest they allow you to bash into stuff harder as in your picture. That's generally not the object. The object is to finess your way thru difficult terrain with as little wear and tare on the vehicle and environment as you can. If you believe that to be true then buy the right load range to do it. If you say hold my beer and watch this then it does not matter. E tires like and need to be beaten to perform as well as a C or D. If you think an E will get you off the beaten path more often then buy one. It's a great tire for a newb to bash his way around until he learns the ropes.

 

[OSV]

That picture is not of a tire forming with the shape of the obstical.

well if the tire isn't deforming to fit the shape of the obstacle in that photo, what is? are you claiming that the rock is deforming to fit the tire? lol, no.

I run the best of everthing.

no, you don't run the "best of everything", you've already admitted to running junk tires that are over 10 years old: http://www.expeditionportal.com/forum/threads/160352-I-need-a-hardcore-Jeep-tire/page2

in that thread you were told "Tires are only designed to last 6 years due to ozone deterioration"... you ignored that advice, and vulcanized a rotten tire.

the ntsb is very clear on the dangers of running rotten tires like yours: http://www.ntsb.gov/news/events/Documents/2014_Tire_Safety_SYM_Panel_4b_Kane.pdf

For sake of conversation let's say an E has a stronger sidewall. A D8 dozer has steel tracks

you've already confused rock vs. rubber, now it's steel vs. rubber, lol

 

[Coachgeo]

Stumps info made perfect sense to me. There is a difference to Finesse driving wrapping a tire around a rock for traction and a tired wrapped around a rock from ramming said tire into a rock. In a picture they can look similar...... in reality the forces to parts and molecules in the material are significantly different.

His Steel tracks as an analogy (not a comparison) of how Stiff sidewalls affect off roading makes sense. As to Ozone deterioration .... very different topic and not relevant to any of this cause it is still in the air (pardon the pun). Too many lobbiest in the pockets of large Govt. organizations who get stuff put thru in order to benefit the big Corp. and not really the public. Not that it is a complete lie..... just maybe 10 years is a huge stretch. 15 years maybe....... But then again.. it is off topic and am certainly no expert.

Now back to topic.... this thread mentioned sidewall cuts due to rocks and other objects (Types of brush) slicing tires. This appeals to me and others in here whose expedition rigs are not Yeep and Yota sized but much larger. We will be real tight on trails, such as my LMTV, others Fuso's, Unimogs etc. Far higher possiblity of slices from such things to cause issues for us than pinches. The items I posted about (side wall protectors) are from an industry that has same issue hence why I brought it up.

 

[Stumpalump]

well if the tire isn't deforming to fit the shape of the obstacle in that photo, what is? are you claiming that the rock is deforming to fit the tire? lol, no.



no, you don't run the "best of everything", you've already admitted to running junk tires that are over 10 years old: http://www.expeditionportal.com/forum/threads/160352-I-need-a-hardcore-Jeep-tire/page2

in that thread you were told "Tires are only designed to last 6 years due to ozone deterioration"... you ignored that advice, and vulcanized a rotten tire.

the ntsb is very clear on the dangers of running rotten tires like yours: http://www.ntsb.gov/news/events/Documents/2014_Tire_Safety_SYM_Panel_4b_Kane.pdf



you've already confused rock vs. rubber, now it's steel vs. rubber, lol

Having fun with the Internet while school is out for the summer?

 

[OSV]

Having fun with the Internet while school is out for the summer?

of course you have to resort to personal attacks, because you don't have any excuse for the stupidity of trying to patch a bad sidewall cut on a rotten tire.

 

[OSV]

Stumps info made perfect sense to me. There is a difference to Finesse driving wrapping a tire around a rock for traction and a tired wrapped around a rock from ramming said tire into a rock. In a picture they can look similar...... in reality the forces to parts and molecules in the material are significantly different.

His Steel tracks as an analogy (not a comparison) of how Stiff sidewalls affect off roading makes sense.

no, it doesn't make any sense at all, and i'll point out that you did make that rather silly sidewall protector suggestion, that got no traction in the thread because it made no sense either.

stump, and others, are directly contracting themselves, by first claiming that all e-rated tires have stiff sidewalls, while at the same time claiming that not all tires are made alike... so if sidewalls from different manufacturers are different, why doesn't that apply to e-rated tires as well.

here is another example of an e-rated tire that is deforming around an object, it got a good review for flexibility: "The Xtreme M/T’s are some of the stickiest tires we’ve ever seen work and all types of rock is their natural habitat. The tires tread and sidewall worked incredibly well in concert! Wedging the aggressive sidewall onto rocks provided enough traction to pull the heavy Jeep up, as well or better, than using the flat tread surface. When the tires wrapped around rocks or folded over, there was always plenty of sidewall thread to keep forward progress. Rarely did a tire slip, even on the most dusty and sandy or wet surfaces. Each Kerfed lug was able to do its job by flexing and grabbing at what it could, to fight for traction." http://www.off-road.com/trucks-4x4/tire-test-the-pro-comp-xtreme-mt-23658.html

 

[Trophycummins]

Just because I feel like this thread needs more pictures.

This is a BFG MT which has a retread vulcanized to the sidewall because the sidewalls been repaired 3 times.

 

[Robert Bills]

here is another example of an e-rated tire that is deforming around an object, it got a good review for flexibility . . . .

^^^ I hope you realize that you are quoting a 2008 article and that the ProComp Xtreme MT2 in 37x12.50R17 is Load Range D, not E.

With all due respect, your ability to use Google to pull quotes out of context is quite good but your reading comprehension and critical thinking skills need some work.

 

[madmax718]

If you pump a C range tire up to psi, it won't like it very much, and it will deform and wear down the center as an over inflated tire, and C range tires generally max out at 50 PSI. E range maxes out around 80 PSI. Its shell is designed firmer, and to offer less flex.

If your carrying a heavy load, C will flex earlier than E's. (of the same tire type, of the same weight truck). I guess you could use a E, but you can also use an F. Strength against cuts has more to do with sidewall design (how high the tread goes up the side), or type of sidewall material.

But its not like they don't test this:
http://www.nhtsa.gov/DOT/NHTSA/NVS/Vehicle Research & Test Center (VRTC)/ca/Tires/811797.pdf

BTW, michelin XPS traction uses a full steel case- It may or may not prevent sidewall cuts. I've had steel sidewall tires ripped apart as well. (not from a rock).

 

[Stumpalump]

^^^ I hope you realize that you are quoting a 2008 article and that the ProComp Xtreme MT2 in 37x12.50R17 is Load Range D, not E.

With all due respect, your ability to use Google to pull quotes out of context is quite good but your reading comprehension and critical thinking skills need some work.

Pro comp is not even a tire company. It's nothing but a TransAmerica sales group that gets companies to whore out cheap products with a fancy name on it. They are called pro-crap for a reason. Cooper made some of their cheapest tires with their name on it for a while but I think it's all China now. Not worth looking up because they buy the cheapest crap they can get with their name on it no matter who makes it for them.

 

[Robert Bills]

. . . Strength against cuts has more to do with sidewall design (how high the tread goes up the side), or type of sidewall material.

But its not like they don't test this:
http://www.nhtsa.gov/DOT/NHTSA/NVS/Vehicle Research & Test Center (VRTC)/ca/Tires/811797.pdf

The following quotes from the Abstract and the Executive Summary in the linked NHTSA report are quite illuminating:

From the Abstract:

. . . Six passenger tire models were also tested using an experimental sidewall bruise/strength test and generated statistically different levels of bruise width, penetration, and rupture force between 1-, 2-, and 3-ply sidewall tires. [Emphasis added.]

From the Executive Summary:

The final goal of the agency research was to evaluate tire sidewall strength/bruise resistance. A sidewall test was proposed that used existing FMVSS tread strength test fixtures in an attempt to duplicate the sidewall bulges or broken cords seen in tires damaged during service. This method was used on five passenger and two light truck tires to examine the concept. The sidewall strength results show a difference between tire sidewall constructions. These results suggested plunger penetration and breaking force were significantly influenced by the number of plies in the tire sidewall. [Emphasis added.]

The NHTSA report supports what Stumpalump, I and several others have been saying all along, specifically that sidewall strength is influenced more by the number and type of plies than by load carrying capacity rating, i.e., that generally speaking an offroad tire with 3-ply sidewalls will have more puncture resistant sidewalls than a similar tire with a greater load carrying capacity rating but only 2-ply sidewalls.

The OP's original question was,

"Are there tires out there that have notably tougher sidewalls than my [Dakota Definity load range E A/T] tires that are more suited to my uses or do I just need to chill out and be more careful?"

The answer is yes, there are tires with tougher sidewalls. The OP's tires are a Pep Boys store brand manufactured by Cooper and designed to meet a particular price point. Although given an E load rating, they only have 2-ply sidewalls. Compare that with the Cooper Discoverer ST/Maxx, also an E load rated tire, but with "3-ply “Armor-Tek3®” sidewall construction consisting of two 1,500 denier plies + one 1,000 denier ply.

The ST/Maxx and other Cooper tires with the "Armor-Tek3®” carcass construction are known for their tough sidewalls. The reason is the 3-ply sidewall construction of the Cooper tires, the thickness of the plies and the materials used.

Load rating is simply a measure of how much weight a tire is rated to carry at a particular tire pressure. As demonstrated by the sidewall failure of OP's load range E tire, load rating alone is not a reliable measure of sidewall strength.

 

[proper4wd]

I feel guilty that you guys are being deprived of first hand facts in this thread, so I actually just took 20 minutes out of of my evening to help.

This is a BFG AT KO2, 295/75R16 LOAD RANGE E at 16psi gathered first hand in my own driveway.

On flat ground, spread and contact patch:

And conformed to an obstacle (this rock is about 4-5" tall):

Can we put this silly thought that Load Range E tires "don't work" to bed now??

 

[Robert Bills]

This thread started with a question about sidewall strength after the OP suffered tire damage in the Shasta-Trinity National Forest, my local area, which is known for sharp volcanic rock and debris from the many active logging sites. He was looking for tires better able to handle this particular terrain than his Pep Boys tires.

The current discussion is about sidewall strength not being directly related to load ratings.

Your photos and your condescending attitude have no relevance to the original question or the current discussion.

But thanks for sharing.