Sidewall strength, tire pressure, and tire quality

[Stumpalump]

A 4" rock should not lift your whole truck off the ground but I'm kicking back so I'll go do the same thing with my 4 ply sidewall load range C. It should be worse than yours with 4 ply.



Fwiw I'm friends with the owners of three tire companies. Good enough freinds that one personally vulcanized my tire. Here are some worthless tidbits I picked up from them over the years.
One owns Sand Tires Unlimited. He told me that the highest cost in a tire was the UV chemical in the rubber. I've used 25 year old tires that he made that are still usable because of the compounds he used back then. I picked his brain and today run with only the fastest guys at Glamis and Dumont in a POS car because of his tires cut the way he told me to cut them.

The other designs tires and works directly with China. Hellava guy. Learned about rotating weight and he said if your not focusing on the side by side market you are going out of business. He has a 300hp hyabusa. Yikes!

The last I've know the longest is a real quiet guy I wheeled with many times in Hot Springs AR. He doesn't advertise, sponsor or anything. It was all we could do to get a banner just to say he was affiliated with us on ride put on by one his best buddies. His name is Warren. He told me that anybody can have a tire made by companies like cooper like he does but what you pay for is a higher percentage of natural rubber. That's what makes a tire tuff. Warren owns Interco. He cast one really cheap aggressive tire in Brazil I think it was. They were a horrible 3rd world tire and so soft they would leave black marks on your hand. They sold like crazy anyway so he flew down and had them change the rubber and make them round. Today they are good. That's the story of the Swamper LTB from the horses mouth. I ran his best tire back in the day and still think it's one of the best off road tires ever built. 36 TSL SX.

 

[proper4wd]

Robert, you obviously don't remember how much you and a small number of others have been opining that E tires are inherently inflexible and unsuitable for off road use on light weight and mid weight vehicles.

Myself and several other have provided numerous rebuttals and proof that this is wrong, yet all you have done is morph your argument to suit. The simple fact - as proven here several times now - is that modern E rated tires can be extremely flexible and compliant off road, and they are finely suited for overlanding/trail use.

These are not the 10-ply nylons or concrete block 1980s radials that you grew up with. It's okay to broaden your perspective.

 

[Stumpalump]

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??

Concrete gets harder everyday for 100 years and rubber does the same. Feel an antique car tire and it's like stone. These tires are date code 1604. 12 years and 3 months old. I know.....
I was not sure if you measured your rock but a 4" looked tiny against my 35" so I upsized to be fair.





I used my engineering grade calibration guage not knowing if yours was spot on or not. Pic is edited but straight on its 16 psi on the nose.



The difference that I've been trying to get across is tread area flex. Note the inside of my tire never leaves the ground. My biggest problem was getting on the rock because my vehicle or hood did not raise at all as I was driving on it. I had to get out and look 5 times.





Tried it twice to see if I was on or off a tread block but it's the same. The rock was not quite half way under the tread the first time so I pushed it in to get it there.



Again I never felt the rock (my main argument for buying a C) and the inside stays planted because the tread block moves a lot more on a C.



Would tires that were not 12 years old help flex more? Who cares these lasted this long and flex as good as a new E or better. I only use the rig on the road to get to trails and keep it in a garage is why they lasted. I'll go find a boulder in the yard and take a pict then air down to my trail pressure and take again. You should be able to see what the Staun beadlock does.

 

[Robert Bills]

Dear Poser4WD:

Your reading comprehension and critical thinking skills are apparently as poorly developed as OHV's.

I have never said that a E load rated tire is "inherently inflexible and unsuitable for off road use on light weight and mid weight vehicles." Those are your words, which you have intentionally chosen in order to create a tangential straw man argument so you can appear smart and inflate your own ego while putting down those who don't happen to agree with you. Donald Trump's penchant for bombast has nothing on you.

What I actually said is that E load rated tires are not as compliant over obstacles at trail pressures on a lighter vehicle than a C or D load rated tire would be, which is a true statement, and that running a tire with a load rating greater than necessary often requires one to air down in situations where one might not otherwise need to with a C or D load rated tire, which is also a true statement. It is a matter of degree, not absolutes.

My point all along has been that tire strength, particularly sidewall strength, is not necessarily related to load rating and the number, thickness and construction of sidewall plies are an important consideration in evaluating a tire, that one must consider all features of a particular tire and balance the relative merits and deficiencies to make the best compromise for one's particular needs, and that many owners of lightweight and mid-weight offroad rigs never made a conscious decision to choose an E-rated tire vs. another load rating simply because they wanted a particular tire or tire size and the only load rating available was an E. In other words, many choose an E-rated tire because they think its the only game in town, not because it''s the best load rating for their rig on the terrain they intend to traverse.

The fact is that one doesn't need an E-load rated tire to run the tough trails in a lightweight or mid-weight offroad rig, but the selection of C and D load rated tires with 3-ply or otherwise tough sidewalls is slim for wheels 16" in diameter and larger. That's just the way it is, which is the result of economies of scale, and the size of the offroad tire market in comparison to the size of the tire market in general, not a testament that an E load rated tire is better on every offroad rig in every circumstance.

My opinion has not morphed. Go put words in someone else's mouth.

 

[OSV]

^^^ 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.

wrong, the article repeatedly stated that it's an e-rated tire.

i'm not sure why you feel like you have to shoot your mouth off repeatedly in this thread, given that we've already established your complete lack of experience with these big tires.

"Additional Tire Specs:
Pro Comp Xtreme Mud Terrain
Sidewall Size Print: 37x12.50 18
Weight: 87 pounds
Actual Height: 36.9 tall
Tire Width: 12.5 wide
Tread Width: 10 tread
Load range E
Max Load LBS 3,970
Durometer 67"

 

[Stumpalump]

Up a rock with a straight edge at 16 psi. No wheel spin.



The tread area is what sucks up the bumps that you feel as much as the side.





This is just over 6 psi with 35 in the Stuan (Coyote) inner beadlock. I stuck it right on the side of what could be called the cliff.



You can see how the beadlock holds the tire just right and protects the rim.



The rock after I backed off. 27 psi in the other 3 tires. Locked front and rear.



C or E both get you off road and that's a blast. I had fun in my own yard!

My passion is hualing azz and power sliding thru the big bowls at Glamis sand dunes so I have a desert car. As I told Phil here are the new bling parts. I knocked 27.5 lbs of unsprung rotating weight off with Willwood breaks, aluminum hat single rotor and had my freind machine the outside of the 930 Porche CV joints down before they got polished and coated. Old stuff was similar but had S10 Chevy breaks. I hope these breaks work as well.



That may not seem like a massive weight reduction but the car weighs under 1700 and the tire with a quart of slime on a beadlock rim only weighs 38 lbs. Here it is next to the BFG that I can't hardly lift.

 

[Stumpalump]

wrong, the article repeatedly stated that it's an e-rated tire.

i'm not sure why you feel like you have to shoot your mouth off repeatedly in this thread, given that we've already established your complete lack of experience with these big tires.

"Additional Tire Specs:
Pro Comp Xtreme Mud Terrain
Sidewall Size Print: 37x12.50 18
Weight: 87 pounds
Actual Height: 36.9 tall
Tire Width: 12.5 wide
Tread Width: 10 tread
Load range E
Max Load LBS 3,970
Durometer 67"

I generally don't defend anybody especially I guy I don't know. What I do know is that he has run C, D and E and currently has E on a lite vehicle. That may not qualify him for your argument but he ran Pritchett. I ran the whole thing thru the fee gate. It's a clinic in what works and he went thru it. He also did Rubicon. Unless he slept thru it then that a fine qualifier in my book. Let's add he has been going off road since you were probably born. I bet I have. Enough on us and our experiance. What is yours? What 4x4' have you owned and wheeled? How many sets and in what range tires have you bought? What trails, off road parks or organized off road events have you attended? What website did you get banned from or left that gives you the web wheelers attitude that you have? Last, are you 21 yet?

 

[Robert Bills]

OHV,

I asked if you were aware that the currently available ProComp Xtreme MT2 in 37x12.50R17 is a Load Range D tire. You responded by regurgitating the specs for the 2008 ProComp Xtreme MT 37x12.50R18.

Different tire, and a simple "yes" or "no" would have sufficed.

I may not have as much experience with 37" tires as you seem to claim, however you're the guy who posted on Expo that you started the Rubicon but turned around and went home before you even reached the tough part of the trail. That would render those 37" tires more a fashion statement, wouldn't you say?

See you on the trail.

Or maybe not.

 

[OSV]

OHV,

I asked if you were aware

no, robert, you didn't "ask" anything, there was no question mark in your post, what you did was try to discredit the proof that you were wrong, by attempting to bring an entirely different tire into the discussion and you failed, just like you did when you claimed that load ratings were not a measure of tire strength.

get back to us when you actually have experience with the tires that you keep posting mindless fud about...

 

[OSV]

I generally don't defend anybody especially I guy I don't know.

you can't even defend your own arguments, like that ghetto fix you did with the big sidewall rip on the rotten tire.

you keep telling us how bad e-rated tires are, but you can't speak from first-hand experience, because you are running worn out c-rated tires.

 

[Robert Bills]

In my humble opinion, two members, one a know-it-all from New England and the other an armchair four wheeler from somewhere in Central California, have turned this thread from a useful discussion on sidewall strength, tire pressure and tire quality into their own personal mud pit for the mindless spewing of irrelevancies and attitude.

Congratulations Poser4WD and OSV, I have now added you to my "ignore" list and will no longer have the displeasure of ever reading one of your useless posts again.

Time for me to imbibe a celebratory adult beverage.

 

[OSV]

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.

the thread turned ugly in large part because you went off-topic on page three, with the claim that "when aired down to typical trail pressures an E rated tire will not conform as well to rocks and other obstacles as a C rated tire."

stop blaming other people for behavior that you yourself were engaging in.

 

[Robert Bills]

This message is hidden because OSV is on your ignore list.

Ah, the sweet sound of silence.

Goodnight all.

 

[Stumpalump]

you can't even defend your own arguments, like that ghetto fix you did with the big sidewall rip on the rotten tire.

you keep telling us how bad e-rated tires are, but you can't speak from first-hand experience, because you are running worn out c-rated tires.

You are a troll. I showed you how 12 year old 4 side ply C's out flex and out grip you new E's with pics. I'll do it tomorrow with the first hand experience you say I don't have with one of the two sets of new E's that I already told you I own and use. You have been shown your wrong and you know bought the wrong tires. Crying about it on the web won't fix it but you just can't stop so you troll. I won't hit ignore until I click your name and read all your worthless posts but my bet is Robert has the right idea.

 

[Hilldweller]