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Tire width benefit?

JeepXJ93

JeepXJ93

NAXJA Forum User
Location
CT
I'm going to be getting M/T's for the Jeep soon again and i was about to go to 32's but decided for a 3.5" lift that 31's are fine, I have been running 31x10.50 and i'm happy w/ them, but i found the M/t in a 31x11.50 and was wondering if the wider footprint will benefit mudding/hill climbing at all? I'm assuming the wider the better for mud, but i see more loose dirt and rock than mud. What do you guys think? Thanks for any opinions.
 
You will have problems with hitting your control arms if you don't have aftermarket ones and even those will rub. The rear should be fine. My bro has 35x13.50x15 Toyo MTs and they fit, but there isn't that much room between the inner sidewall and the springs. He has a RE 5.5" lift with fixed upper and lower CA's. We're going to run spacers/adapter or just a full width axle though to get a wider track width.

Troy
 
I would go with the wider tires if you have the right offset of rims. If your on stock rims...I would stay with the narrower tires...which will still rub control arms...but not as bad.
 
a wider footprint would be bad for mud - cause you to float more, rather than dig through the soft stuff and grab the hard underneath...


the wider tires are nice for rocks, and i prefer them because there is more contact with the rocks...

now - more contact means less traction - so dont go to crazy...
traction is the weight on each inch of contact... more inches of contact, means weight on the area of tire in contact - means easier to slip...
 
ahhhh thanks Ranger, so in short for my needs the narrower is a bit better, i dont see too much rock crawling its mostly small mud pits and dirt/loose rock hills and trails. Thanks for the breakdown of the whole traction issue i didnt think about that. 31x10.50 for now
 
MaXJohnson said:
Read that slowly

you might want to check the batteries in your calculator.
Click to expand...

read the statements afterwards...

traction is the friction between the tire and the surface.
more weight on a smaller contact patch will have more friction than the same weight on a larger contact patch...
I run 33x12.50's

i like the wide tires because they allow me more line choices - even the 2" per tire matters in the trails i have ran in the past, so...

what are you trying to say Max? explain please...
 
Anyone who grew up on a farm knows that tall, skinny tires do better in mud and fat tires do better on sand.
As for rocks, I'd say you need to establish a balance of traction for the given contact area, what I might term as tire loading. Weight applied per square inch of tire footprint per a given angle on front & rear.
 
I do not agree with the fact about tires width. A skinny tire is good in the shallow mud when you can hit the hard surface under. But what if that layer of mud is deeper like muck or a swamp? Well thats where flotation come in. The tire width depends on where you wheel and what kind or terrain that you come across. As far as rocks go, its kinda the same thing of the terrain. contact patch has allot to do with it. A skinny tire will fall in some cracks that wider tires would not. But a wide tire can get you in trouble too. Tire bite and costruction and inflation is another factor. I myself run a 18 inch wide tire on my cherokee. It has great flotation in the mud in the northeast and get me out of trouble with some of the rocks. The fact that i can airdown to low pressures and fold the tire around rocks more than a skinny tire can also helps me out. On smoth rock my tires suck, they cant bite anything so i am relying on the contact patch which has a small amout of weight on it. IT DEPENDS ON WHERE AND WHAT YOU WHEEL AND WHAT YOU LIKE!!!!


Oh yea about the farm thing it depends on where you farm. Around here we have black dirt and when that gets wet there is no bottom, only 6 or 8 wheelers will go though it.

Pete
 
What PB said

x2

Also....I don't think the width of the tire matters when talking about traction on ROCKS...generally....If you have the whole tire touching....then traction is good (regardless of tire size). And if your only using part of the tire....then what does the size of the tire have to do with traction...only the part you are using matters.

BUT...as RANGER said...sometimes those wider tires open up an otherwise impossible line.
 
I just switched from a 33x12.50 down to the TSL 32x9.50. I had stock rims and the 12.50s were way too wide. I just tried my 32x9.50s out and they rock. I'm a big fan of narrow tires for in the woods. The TSL 34x10.50s LTBs are awesome too. The weight of your vehicle rests on a smaller contact point, forcing the narrow tire into the ground and biting, rather than floating on top of soft stuff and spinning. The wide footprint spreads out over rocks and gives you more traction on rocks if you are a rock guy, but for trails, woods or ruts tall and narrow it the key!
 
JeepXJ93 never said what rims he is running. On stock rims, 10.5" tires come rather close to the rear springs, and 11.5" tires on the same rims will come 1/2" closer.

I wouldn't do it.

Aftermarket rims with less backspacing would make this comment irrelevent.
 
XJ_ranger said:
now - more contact means less traction - so dont go to crazy...
traction is the weight on each inch of contact... more inches of contact, means weight on the area of tire in contact - means easier to slip...
Click to expand...
Actually more contact equals the same traction. The area of contact doesn't matter. If the amount of weight remains the same than the traction/friction remains the same. It's just distributed differently. The larger the contact patch is the less friction there is per square inch, but there are more square inches of said friction. It all evens out.

K
 
XJ_ranger said:
read the statements afterwards...

traction is the friction between the tire and the surface.
more weight on a smaller contact patch will have more friction than the same weight on a larger contact patch...
I run 33x12.50's

i like the wide tires because they allow me more line choices - even the 2" per tire matters in the trails i have ran in the past, so...

what are you trying to say Max? explain please...
Click to expand...

contact area X contact pressure X coefficient of friction = grip (traction)

The coefficient of friction is not static and falls off slightly as contact pressure increases, so doubling the contact pressure doesn't quite double the available traction. Increasing the pressure per square inch due to a smaller contact patch will result in less grip than the same weight spread over a larger contact patch. Just the opposite of what you are saying.

Going beyond rubber to surface adhesion, in most off-road stiuations, traction is more dependent on mechanical grip. Mechanical grip depends on the rubber interlocking with a rough surface at the micro level, plus tread edges interlocking with the terrain and the tire carcass wrapping around rocks at the macro level for maximum traction. In this respect, a wider tire at low pressure is almost always superior. The exception already stated being shallow mud (and snow).
 
MaXJohnson said:
contact area X contact pressure X coefficient of friction = grip (traction)

The coefficient of friction is not static and falls off slightly as contact pressure increases, so doubling the contact pressure doesn't quite double the available traction. Increasing the pressure per square inch due to a smaller contact patch will result in less grip than the same weight spread over a larger contact patch. Just the opposite of what you are saying.

Going beyond rubber to surface adhesion, in most off-road stiuations, traction is more dependent on mechanical grip. Mechanical grip depends on the rubber interlocking with a rough surface at the micro level, plus tread edges interlocking with the terrain and the tire carcass wrapping around rocks at the macro level for maximum traction. In this respect, a wider tire at low pressure is almost always superior. The exception already stated being shallow mud (and snow).
Click to expand...

It still depends on what surface you are on....skinny for shallow mud, wide for mud that is deep, and also wide for sand.
Airing down the tire makes a wider foot print*

After reading your statement 10 more times, i finaly understand it!
And realize that my above statement basicaly says nothing that you already dident point out....

bty do u have to speak with such big words?!!?!?
 
Last edited:
MaXJohnson said:
The coefficient of friction is not static and falls off slightly as contact pressure increases, so doubling the contact pressure doesn't quite double the available traction.
Click to expand...
I knew there was something I was missing. Thanks for the info on coefficient of friction not being static.

K
 
yup

i agree with everything said here...

and i run wider tires rather than skinnier, but in margin - i run 33x12.50's instead of 33x9.5's or 33x16.5's

it is all dependant on what you run - and saddly enough i cant justify building for anything other than what i run, which 90% of the time is road... cold hard pavement...

wider tires have a negitive effect on gas milegae - might affect your decision as well...
 
Snarky said:
bty do u have to speak with such big words?!!?!?
Click to expand...


ENGLISH, learn it; use it.




:lecture:
 
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