Beartracker

How much air do you guy's like to run in your 6 ply 31" tires for on and off road wear and tear? I'm off road about 3-4 days a week but nothing real bad, mostly old logging and mining roads. Got my new Wild Country TXR tires the other day and they are 6 ply and are on my 01 Tacoma and will be carrying about 500 extra lbs all the time including Myself, truck bed tool box, all my tools and so on.
They are 265/75/R16 .
I'm running about 29 in the front and 32 in the rear right now. Thanks, Mike

lee

i run 30 up front, 32 in back... no real idea why, sullivan tire did that when they installed my new tires so i just keep it that way.

toyota2

I usually run 32 all around for street driving. Any reason to run a little less up front? On a side note beartracker looking at your sig. you do not have a lift have you had any rubbing with the tires. I have an 02 ex.cab but was told that size might rub at full lock.

Thanks

Beartracker

Thanks Lee, sounds like we are real close. When I ask the guy who put mine on how much air did he put in them he stated 32 in the front and 35 in back. That just seemed a little high to me. Guess I'll just have to see how they are wearing over time and go from there. Thanks again, Mike

Beartracker

This Toy came with 31" from the factory and they rub just a bit if I'm cranked one way or the other and hit a low bumb on one side or they other but it's very minor. Just turning it, it does not seem to rub. You can't even see any mark on the tire where it's hitting so, it's very little. This is the third set for this truck.
Keep in mind that different tire companies seem to measure differently. Some will be slightly over and some slightly under.
The reason for more air in the back than the front on a truck is to allow for the extra weight you may place in the bed of the truck, Mike

toyota2

Mike

Thanks for the Quick reply. My Tacoma came with 265/70/16 and its about time for new tires and was wanting to up size to the 75's but was told they might rub. I was looking at bfg at's if that matters.

Thanks again
Shawn

rimpainter.com

265/75/16's here. 35psi on the street, 25psi off-road.

Beartracker

Shawn, If you get much rubbing it wont be enough to hurt anything and the tires will wear down and that will take care of that,Lol.
You may want to try a place like Wal Mart or a major tire dealer. Many of them allow you to try them for 30 days and if you don't like them you can bring them back. Mike

96 Runner, Your the first I heard of running that much air. How do they handle and ride for you? How about the wear? Let me know when you get time. maybe I should run mine a little higher .Thanks, Mike

rimpainter.com

Handles/rides fine, no problems. My max psi is 44. I keep a close eye on the shoulders of the tire to ensure there is no premature wear, in 20K miles, all is good.

Flamedx4

About 7.6 cu ft. in each...

Flamedx4

ON nearly all vehicles you will run more in the Front than in the Rear, as the weight distribution is nearly always more front than rear. Poper inflation pressure is 100% dependant on the weight the tire actually supports. You would never, ever want more in the rear on a truck - not unless you actually ARE carrying the 'big load' back there. Certainly not in your day-to-day driving. If you load the truck, change the pressure, don't drive it with high pressure all the time. If 32 was correct for the front then 35 would be way too high for the back - the back end would actually have a tendency to slide out on corners! On most trucks the rear weighs a lot less than the front, so the rears will have a lower pressure than the front when properly inflated. On my '90 with the 35s (big tires on a lightweight truck play havoc with proper inflation for tire wear) I run 30 on the front and 26 on the rear. This is a compromise - to wear properly they actually should have even less psi but they get way too spongy and it drives terrible if I go any lower. On my F150 with my current 285/60R18 tires I run 40 in front and 34 in back, with the previous 265/70R17 tires I ran 42 in front and 34 in back. The last set of tires wore evenly across the tread all the way to the wear bars, so I definitely had the pressure right.

Beartracker, don't set your pressure according to what others set - even if they have the same truck and the same tire and rim, how do you know they are doing it correctly? Take some time to find the right pressure for your rig.

The correct air pressure will cause wear to be even across the tread face of the tire. With new tires just watch as the nubs wear off and adjust accordingly. Or, make a chalk mark across the face and drive on a straight road for a bit and look to see where it's wearing the chalk off. If it wears in the middle, let air out. If it wears on the edges add more air.

Tire rotation is still required because fronts and rears wear differently due to steering & cornering.

{By the way - the 7.6 cu ft answer was arrived at by calculating the volume of a 31x10.50R16 tire (3.3 cu ft) and inflating it to 33psi (2.36 atmospheres.) All arbitrary numbers to be sure and probably bad science too...}

Beartracker

Wow, I have been driving trucks for over 40 years and have never heard of anyone not keeping the back tires 2-3 lbs. heavy.
Also you have to keep in mind that 6 ply will take more air than 4 ply and your driving habbits, style ,road conditions and weather will have allot to do with proper tire inflation so the idea of finding out what the proper inflation is for my size tire can go out the door,Lol. A person who lives on the Arizonia desert where it's 110 all day will not want to use the same air as the guy who lives in the north pole either. Way to many variables to try to get scientific about such things.
My question was to people driving with my size tire and set up under close to the same conditions and styles. A few days a week off road and a few on but without rock climbing and going through mud bogs. One person stated that they have 20,000 miles on there tires and they are wearing fine. Nothing scientific about that. Just proven facts.My last tires (same size but 4 ply) and not as agressive lasted me 30,000 by running 28 lbs. in the front and 31 in the back and they have many miles left on them. Just rotate them when due and change the preasure acordingly. Never had a problem doing that in all these years.
Just wanted to see what others have had work for them under the same conditions over time. Thanks for your info though, Mike

Gregg

I never go less than 32psi frt or back. 40 psi back when hauling/towing heavy stuff. Generally stay around 35psi more mileage help. Only in the MN winters do I drop down to 30psi for traction and balance out my wear pattern from too high in the rest of the year.
'01 taco, Dcab,4x4, TRD, 275/75/16 Mich M/S LTX, 6 ply. and yes they just barely rub on one side in the front. Perfectly acceptable.

Beartracker

Greg, That sounds right to me. I'm going to try 31 front and 33 back for now just to see how it feels. Different tires will act different even if they are the same size as we all know. This is my first set of Wild Country TXR but the size is the same as the rest of them. I have heard nothing but good things about these tires and would like to try to get the best performance and longevity out of them. Thanks for your input on this subject. Love Minn. and hope you guy's are staying a little cooler than we are. In the 90's almost every day here , Take care, Mike

SolidDigital

Flamed is right, I always run more in the front also..

Silver_Truck

Good post flamed....I also run more in front then the rear and most people with trucks that I know do the same and with regards to the big tires being a pain to get to good inflation pressures I find that to be true also...but running bias tires takes away some of that squirleyness I run 19 in the rear and 21 up front and still don't get even wear. the rears wear quickly in the centre if I fill em up as much as the fronts

Beartracker

Different people do things in different ways I guess. We never did it that way in Ohio, West Virginia or PA that I know of and as stated above I have been driving trucks for many years and 4x4 was my first when I was 16 and I'm 59 now.
You have to keep in mind that we were always hauling something at one time or another so it was senseless to air your rear tires up and down several times a week. Never had tires wear uneven from that. In fact the back always wears better than the front no matter what you do due to all the turning thats done every time you wheel or just drive, unless your a flat lander with straight roads only,Lol.
Never had any trouble with the rear end sliding because of more air either. The 2 or 3 lbs of air I 'm talking about never hurt a thing for me or many, many others. But it sure makes a difference when I want to toss an extra 200 lbs of stuff in the back. Mike

Flamedx4

The amount of air pressure in a tire is dependant on load. This is fact, not just my opinion. An empty truck has a terrible weight balance, around 65/35 or even more skewed on some. So, the front tires are carrying more weight. Therefore they need more air. It's just that simple.

Unless of course you are always carrying a load, then you need to add air to accomodate the load. Go find the tire manufacturer's load charts and see for yourself.

Beartracker

Flamed, Don't get me wrong here I'm not trying to prove you wrong or even argue with you. I just can't see where you are getting your facts.
Every vehical I have ever owned has recommended more air in the back tires than the front and in some cases even air preasure all the way around. But NEVER have I seen where they recommend the FRONT tires have more preasure than the rear.
Here is what's on the tire preasure recommendation on the sticker on the inside of my 01 Tacoma door and in the owners manual:

225/75/R15 26 front 29 rear

265/70/R16 26 front 29 rear

They have one that they list as 26 front and 26 rear with a code beside it. Don't know what the code is.

In the manaual they list even more sizes and one is 29 front and 32 back.
NO where do they state or recommend more preasure in front than in the rear.

Flamedx4

Not offended, conversation/debate/exchange of ideas is all good.
Here's the thing - if you put the max payload in your bed, those pressures probably will be correct. Manufacturers have to hedge - if they tell you it's okay to haul 1500 pounds they must tell you to keep enough air in your tires to do that. I have on many occasions in the past 20 years sat down with Bridgestone and Goodyear tire engineers and worked on tire issues, both to allow me to include the correct info in our owners manuals and to respond to litigation. (Blowout causes crash = insurance company sues vehicle manufacturer....)

All tire manufacturers publish charts to tell you how much weight the tire will support at a given air pressure. Correct inflation pressure varies with the weight the tire must support. More weight = more air pres. Period. Too little or too much can both be disastrous.

With something like a 4runner and all your stuff in it the weight will be pretty evenly distributed front to rear and the tires would wear pretty evenly with pressures about the same front and rear - but with pickups the rears want to wear the center faster (indicating overinflation - need to reduce tire pressure) and the fronts want to wear a rounded crown in the center (indicating underinflation- need to increase pressure.) This is true for most cars too but REALLY true for pickups where the rear is so light.

The correct tire pressure for any tire - car, truck, bus, semi - doesn't matter - is the amount of air it takes to get the wear evenly. But, this isn't always possible. To get 35s on a Yota to wear properly they'd need about 12 pounds - horrible for ride and handling and leading to excess hysteresis - heat buildup! Of course, extremely mismatching the tire to the rig in this fashion messes things up a bit and you just have to compromise best you can.