User Tag List

Reply
 
Thread Tools Rate Thread Display Modes
Old 07-29-2013, 05:10 PM #16
the great him's Avatar
the great him the great him is offline
Elite Member
 
Join Date: Nov 2010
Location: Earth
Posts: 6,454
Real Name: Isaac
the great him is a name known to all the great him is a name known to all the great him is a name known to all the great him is a name known to all the great him is a name known to all the great him is a name known to all
the great him the great him is offline
Elite Member
the great him's Avatar
 
Join Date: Nov 2010
Location: Earth
Posts: 6,454
Real Name: Isaac
the great him is a name known to all the great him is a name known to all the great him is a name known to all the great him is a name known to all the great him is a name known to all the great him is a name known to all
ok you are proving physics wrong glad to know
__________________
if a*sholes could fly this place would be an airport -2004 GX470 spm -97 SR5 3.4, SCS Stealth 6's w/305 70 17s MTRs, Icon 2.5" RR w/700#coils, OME861s w/Icon tacoma 2.0 RR, ARBs w/nitro 4.88, PIAA LED lights, 170amp CS144, ARB snorkel, ARB bumper w/xd9000ce, CBI swingout loaded, BudBuilt skids, lil skip tank skid, sliders, LCE 231s(d&s), first gen roll bar mod, LED interior/dash lighting, B&M 70624+perma cool w/electric fan, dual electric fanshttp://www.toyota-4runner.org/3rd-ge...ld-thread.html
http://www.metaltech4x4.com/
the great him is offline   Reply With QuoteReply With Quote
Old 07-29-2013, 05:44 PM #17
the great him's Avatar
the great him the great him is offline
Elite Member
 
Join Date: Nov 2010
Location: Earth
Posts: 6,454
Real Name: Isaac
the great him is a name known to all the great him is a name known to all the great him is a name known to all the great him is a name known to all the great him is a name known to all the great him is a name known to all
the great him the great him is offline
Elite Member
the great him's Avatar
 
Join Date: Nov 2010
Location: Earth
Posts: 6,454
Real Name: Isaac
the great him is a name known to all the great him is a name known to all the great him is a name known to all the great him is a name known to all the great him is a name known to all the great him is a name known to all
ok i see what you are saying, and your theory is correct, lb for lb yes a p rated tire will carry a greater load, but in reality you can run a E rated tire at 25psi and it will hold the weight of a 4runner just fine, you CAN NOT do the same thing with a P rated tire, it simply wont work... if you do not believe me try it.

you are trying to do a lb for lb comparison but your only control is tire size and, you have too many variables to make your statements concrete.

so i can carry a load of 15,000lbs @80psi with my tires, my 4runner lets say weighs 1/3 that @5000lbs(thats with a average daily load roughly). now for my tires to support that load i should only need 1/3 of their max psi correct? yes so i really should only need 26.4psi per tire to hold the weight properly, and i can assure you that at even 25psi in my tires there is no abnormal squatting or increase in rolling resistance, or increased consumption of fuel. now lets try the same thing with your passenger rated tire your max load is 11332lbs @ 35psi. so 5000lbs of the 11332 is roughly 44% so we will run our P rated tires at 44% of 35psi which is 15.4psi... does anyone see a problem yet? you need to run your P rated tires are a high percentage wise psi than you do an E rated tire, no way no how will a p rated tire cary more load then an e rated tire per psi, even in a ratio comparison such as this...

and if you are gonna try and tell me that the side walls will break down faster with an E rated tire run at a lower psi than recommended im not gonna buy it, besides even if it did, i still only have a 5000lb truck, not a 10,000lb truck so im not worried in the least that i might have lost 20% of my tires load carrying capacity

i get your theory, and it works in theory but in reality its never gonna work out, physics and natural "laws" and science and math say otherwise, so does the real world and everyday usage.

now what i will agree on is that a P rated tire will have a much softer ride at 35psi then a E rated tire will at 80psi, but just as i have shown above there is no need to run the E rated tire at 80psi in our rigs unless you are looking to the up-most possible mpg say like on a road trip where 98% of your driving will be hwy driving. other than that you can run your E rated tire at a much lower psi, say like 35psi and have at least as nice if not nicer ride than the P tire, all the while having a tire that has deeper treat, and a thicker carcass to help hold up to road hazards like potholes or glass or curbs ect. and with a P rated tire there is as not much leeway in your psi adjustments as there is in a E rated tire, you cant just drop 10lbs and call it good cause you want a softer ride or you cant increase psi cause you want better mileage or you want to carry a heavy load like you can with the E rated tire. nor will the tire hold up off road to rock and sticks or other dangers like an E rated tire will, not to mention the shallower tread.
__________________
if a*sholes could fly this place would be an airport -2004 GX470 spm -97 SR5 3.4, SCS Stealth 6's w/305 70 17s MTRs, Icon 2.5" RR w/700#coils, OME861s w/Icon tacoma 2.0 RR, ARBs w/nitro 4.88, PIAA LED lights, 170amp CS144, ARB snorkel, ARB bumper w/xd9000ce, CBI swingout loaded, BudBuilt skids, lil skip tank skid, sliders, LCE 231s(d&s), first gen roll bar mod, LED interior/dash lighting, B&M 70624+perma cool w/electric fan, dual electric fanshttp://www.toyota-4runner.org/3rd-ge...ld-thread.html
http://www.metaltech4x4.com/
the great him is offline   Reply With QuoteReply With Quote
Old 07-29-2013, 05:52 PM #18
the great him's Avatar
the great him the great him is offline
Elite Member
 
Join Date: Nov 2010
Location: Earth
Posts: 6,454
Real Name: Isaac
the great him is a name known to all the great him is a name known to all the great him is a name known to all the great him is a name known to all the great him is a name known to all the great him is a name known to all
the great him the great him is offline
Elite Member
the great him's Avatar
 
Join Date: Nov 2010
Location: Earth
Posts: 6,454
Real Name: Isaac
the great him is a name known to all the great him is a name known to all the great him is a name known to all the great him is a name known to all the great him is a name known to all the great him is a name known to all
Quote:
Originally Posted by gm350reratliff View Post
I believe the numbers are correct for the 265/70/17 size. Other sizes in load range E will be rated higher, some less. I know for a fact my 285/70/17 BFG ATs (load range E) that were on my silverado were rated at 3195lbs @80 psi. The same size BFG ATs that were on previously (load range D) were rated at 3195lbs @ 65psi. I have seen some load range E tires with over 4000lbs rated capacity while others less than 3000. His chart seems ok to me.
yeah i see that now, i was reffing my tires, i over looked that his graph was off of a 265, my bad, but then again he is also quoting two different tire sizes himself which imo adds to the confusion as well. this goes to a point i was making as well though, that different tire manufactures will rate their respective E rated tires all differently... your 285 70 17 BFG ATs are rated at 3195lb @80psi, while my 285 70 17 Nitto Terra Grapplers are rated at 3750lbs @80psi.... its all extremely variable and one little change in any think can throw things way off... heck there are even different ratings among the E rated tires of the same size and make and design...
__________________
if a*sholes could fly this place would be an airport -2004 GX470 spm -97 SR5 3.4, SCS Stealth 6's w/305 70 17s MTRs, Icon 2.5" RR w/700#coils, OME861s w/Icon tacoma 2.0 RR, ARBs w/nitro 4.88, PIAA LED lights, 170amp CS144, ARB snorkel, ARB bumper w/xd9000ce, CBI swingout loaded, BudBuilt skids, lil skip tank skid, sliders, LCE 231s(d&s), first gen roll bar mod, LED interior/dash lighting, B&M 70624+perma cool w/electric fan, dual electric fanshttp://www.toyota-4runner.org/3rd-ge...ld-thread.html
http://www.metaltech4x4.com/
the great him is offline   Reply With QuoteReply With Quote
Old 07-29-2013, 07:41 PM #19
Canazes9's Avatar
Canazes9 Canazes9 is offline
Member
 
Join Date: Jun 2013
Location: Texas
Posts: 942
Real Name: David
Canazes9 is on a distinguished road
Canazes9 Canazes9 is offline
Member
Canazes9's Avatar
 
Join Date: Jun 2013
Location: Texas
Posts: 942
Real Name: David
Canazes9 is on a distinguished road
Somebody help me out please - why are we comparing optimum inflation pressures of P-Metric tires vs LT tires for an indicated Gross Vehicle Weight of 8800 pounds for a vehicle that has a GVWR of 6300 pounds (2013 SR5 4x4)?

Load carrying capacity isn't the only factor that affects vehicle manufacturer's recommended inflation pressures. Vehicle manufacturer's can and do adjust their inflation recommendations for their tires based on GVWR, mileage, vehicle handling & safety factors and passenger comfort.

From the chart information provided 44psi in an LT tire is equivalent to 32psi as far as load carrying capability. When you realize that the load carrying capacity exceeds GVWR recommendations by about 2500 pounds you must assume that Toyota had other reasons for recommending 32psi in their P rated tire applications.

The greatly stiffened sidewalls of LT tires (esp so those with higher load ratings) help offset some of the reasons for the inflation requirements on the P metric tire in excess of the vehicles load carrying capacity. As long as you don't drop below your min GVWR rating of 6300 pounds you should be fine. As the vehicle manufacturer doesn't provide inflation pressure recommendations for LT tires, you are on your own to figure it out (other than min load carrying capacity).

At 35 psi, (reading the chart, I didn't dig through the data tables for a precise number) the load carrying capacity of an LT tire is ~1875 pounds for a GVWR of 7,500 pounds. As long as you do not exceed the speed rating for the tire (99mph for my MT tires) and maintain the min 35psi inflation you have not exceeded the tires performance parameters. You may (probably will) find that your optimum inflation pressure for the best combination of mileage/comfort/handling will require a higher pressure. Without manufacturer's rec's you are on your own to experiment and figure it out for yourself.

After much experimentation, I have found 38psi to be the sweet spot (according to me!) for my Tacoma w/ E load MT's. I will have to experiment with the T4R when I upgrade the tires, I'm betting I'm going to like 40psi but we will see. Just like my Tacoma, I suspect that when towing I may like additional pressure in the tires, esp the rears. There is no need to inflate LT tires to 44psi unless you plan on loading your T4R up to 8800 pounds GVW....

David
Canazes9 is offline   Reply With QuoteReply With Quote
Old 07-29-2013, 08:04 PM #20
BlackWorksInc's Avatar
BlackWorksInc BlackWorksInc is offline
Elite Member
 
Join Date: Feb 2011
Location: Bend, OR
Posts: 9,906
BlackWorksInc is a splendid one to behold BlackWorksInc is a splendid one to behold BlackWorksInc is a splendid one to behold BlackWorksInc is a splendid one to behold BlackWorksInc is a splendid one to behold BlackWorksInc is a splendid one to behold BlackWorksInc is a splendid one to behold BlackWorksInc is a splendid one to behold
BlackWorksInc BlackWorksInc is offline
Elite Member
BlackWorksInc's Avatar
 
Join Date: Feb 2011
Location: Bend, OR
Posts: 9,906
BlackWorksInc is a splendid one to behold BlackWorksInc is a splendid one to behold BlackWorksInc is a splendid one to behold BlackWorksInc is a splendid one to behold BlackWorksInc is a splendid one to behold BlackWorksInc is a splendid one to behold BlackWorksInc is a splendid one to behold BlackWorksInc is a splendid one to behold
Wow, I knew the 5th gens were porky, but really? 6,300lbs?

You also have to remember that you will increase the weight ontop of GVWR with extra passengers, cargo, and towing; the weight of a trailer on the vehicle imparts load as well. So this may be why the pressure rating is higher than the vehicle's GVWR in an attempt to include all reasonable weight additions to the vehicle.

In any case, Toyota even agrees that LT tires need more pressure. There's a service campaign to replace TPMS modules on TRD FJ Cruisers (They came equipped with optiona LT Tires) because of a higher tire pressure being needed and the baseline P rated tire minimum programmed value being too low (don't ask me why they just don't reflash the module... its Toyota, they haven't been very flash happy in their history...)

Perhaps we need to scrap what we're arguing about right now and start from the ground up. What are the differences in the construction of P, LT, and Commercial tires and how does this affect the tire's flexibility, load, then go into the air pressure. I think that might help allievate confusion.
BlackWorksInc is offline   Reply With QuoteReply With Quote
Old 07-29-2013, 08:06 PM #21
Canazes9's Avatar
Canazes9 Canazes9 is offline
Member
 
Join Date: Jun 2013
Location: Texas
Posts: 942
Real Name: David
Canazes9 is on a distinguished road
Canazes9 Canazes9 is offline
Member
Canazes9's Avatar
 
Join Date: Jun 2013
Location: Texas
Posts: 942
Real Name: David
Canazes9 is on a distinguished road
Quote:
Originally Posted by BlackWorksInc View Post
Wow, I knew the 5th gens were porky, but really? 6,300lbs?

In any case, Toyota even agrees that LT tires need more pressure. There's a service campaign to replace TPMS modules on TRD FJ Cruisers (They came equipped with optiona LT Tires) because of a higher tire pressure being needed and the baseline P rated tire minimum programmed value being too low (don't ask me why they just don't reflash the module... its Toyota, they haven't been very flash happy in their history...)

Perhaps we need to scrap what we're arguing about right now and start from the ground up. What are the differences in the construction of P, LT, and Commercial tires and how does this affect the tire's flexibility, load, then go into the air pressure. I think that might help allievate confusion.
6300 pounds is the GVWR - the vehicle, fuel, passengers, cargo, everything. I don't remember the curb weight off the top of my head, around 4700 pounds if I remember correctly.

I agree w/ extra pressure, at the very least you've got to go up to 35psi, but beyond that you're going to have to experiment a little.

David
Canazes9 is offline   Reply With QuoteReply With Quote
Old 07-29-2013, 08:08 PM #22
BlackWorksInc's Avatar
BlackWorksInc BlackWorksInc is offline
Elite Member
 
Join Date: Feb 2011
Location: Bend, OR
Posts: 9,906
BlackWorksInc is a splendid one to behold BlackWorksInc is a splendid one to behold BlackWorksInc is a splendid one to behold BlackWorksInc is a splendid one to behold BlackWorksInc is a splendid one to behold BlackWorksInc is a splendid one to behold BlackWorksInc is a splendid one to behold BlackWorksInc is a splendid one to behold
BlackWorksInc BlackWorksInc is offline
Elite Member
BlackWorksInc's Avatar
 
Join Date: Feb 2011
Location: Bend, OR
Posts: 9,906
BlackWorksInc is a splendid one to behold BlackWorksInc is a splendid one to behold BlackWorksInc is a splendid one to behold BlackWorksInc is a splendid one to behold BlackWorksInc is a splendid one to behold BlackWorksInc is a splendid one to behold BlackWorksInc is a splendid one to behold BlackWorksInc is a splendid one to behold
You're right, was thinking something else for GVWR; GVWR does not include trailers/towing weights though.

Curb weight 4th gen is about 4,300lbs, 5th is about 4800lbs on the higher end, 4,400lbs lower end (I doubt that number though) and for fun, 1st gens are around 3,700lbs. Pretty damn porky for an SUV that only has a V6...

Last edited by BlackWorksInc; 07-29-2013 at 08:11 PM.
BlackWorksInc is offline   Reply With QuoteReply With Quote
Old 07-29-2013, 10:55 PM #23
JB.'s Avatar
JB. JB. is offline
Senior Member
 
Join Date: Dec 2004
Location: So. Nevada
Posts: 3,161
JB. will become famous soon enough
JB. JB. is offline
Senior Member
JB.'s Avatar
 
Join Date: Dec 2004
Location: So. Nevada
Posts: 3,161
JB. will become famous soon enough
Quote:
Originally Posted by the kid View Post
ok i see what you are saying, and your theory is correct, lb for lb yes a p rated tire will carry a greater load, but in reality you can run a E rated tire at 25psi and it will hold the weight of a 4runner just fine, you CAN NOT do the same thing with a P rated tire, it simply wont work... if you do not believe me try it.
I love easy experiments that bring real evidence to endless discussion. I perform them whenever possible. Unfortunately, I don't own P tires but otherwise I'd be happy to run them at 25psi for a while (with due caution). I'm sure cornering would be less stable and mpg would suffer, but what else is it you imagine would happen?

I'm not saying LT tires are bad -- look at my sig. If someone is going to beat up their tires offroad, by all means get some. But I do dispute the common idea that they're the only way to go and are superior to P type tires. P-metric tires generally outperform them on pavement, especially in wet conditions where the water is not deep.

LTs simply have certain performance characteristics that may or may not be desirable depending on application. One important way they're different is the load/inflation curve and it's something worth knowing. The tire load reserve on 4th and 5th gens is generous enough it mostly doesn't create a problem but it could create one on, say, a 3rd gen with the smallest stock tire size offered and then switched over to an LT of the same size with no adjustment in pressure.

As far as the sidewall, here's a small point to consider. Yes, the LT sidewall is stiffer but the deeper tread and thicker carcass mean there is less air volume inside a tire that has the same outside dimensions. The P tire holds more air volume at the same psi. I'd love to do the same deflection experiment on a P tire that I did on the previous page. I'll bet the curve would look nearly identical (please feel free to contribute some experiments along these lines yourself.) Also, I specifically asked the tire engineer about sidewall life, specifying that size, load and (low) psi were the same between the tires and that rough treatment of the tire was not part of the equation. He said he would expect the aired down P tire sidewall to last longer. This is mostly academic and irrelevant for offroading, but it illustrates a non-intuitive point that helps demonstrate why the load/inflation curves can be different between the two.

But the Tire and Rim Association publishes the load tables, not me. If you think they are misleading, write to them.
__________________
2005 Limited V8
Bilstein 5100 at .85
5th gen SR5 springs
BFG AT KO2 LT265/70/17 Load C (Replaced Revo 2 LT265/70/17 Load E)
Hanna sliders

Last edited by JB.; 08-01-2013 at 06:13 AM.
JB. is offline   Reply With QuoteReply With Quote
Old 07-29-2013, 11:18 PM #24
JB.'s Avatar
JB. JB. is offline
Senior Member
 
Join Date: Dec 2004
Location: So. Nevada
Posts: 3,161
JB. will become famous soon enough
JB. JB. is offline
Senior Member
JB.'s Avatar
 
Join Date: Dec 2004
Location: So. Nevada
Posts: 3,161
JB. will become famous soon enough
Quote:
Originally Posted by the kid View Post
....this goes to a point i was making as well though, that different tire manufactures will rate their respective E rated tires all differently... your 285 70 17 BFG ATs are rated at 3195lb @80psi, while my 285 70 17 Nitto Terra Grapplers are rated at 3750lbs @80psi.... its all extremely variable and one little change in any think can throw things way off... heck there are even different ratings among the E rated tires of the same size and make and design...
Dude, you're killin' me.

I'm trying to be polite (I didn't even bring up your advice in the other thread to run an LT at lower than P road pressure to break it in) but you've had ample opportunity to check out the sources which you apparently refuse to do. Tire size and type, alone, determine load capacity, regardless of brand. Again, write to the TRA.
__________________
2005 Limited V8
Bilstein 5100 at .85
5th gen SR5 springs
BFG AT KO2 LT265/70/17 Load C (Replaced Revo 2 LT265/70/17 Load E)
Hanna sliders

Last edited by JB.; 07-29-2013 at 11:34 PM.
JB. is offline   Reply With QuoteReply With Quote
Old 07-30-2013, 09:40 AM #25
scanny's Avatar
scanny scanny is offline
Senior Member
 
Join Date: Aug 2010
Location: Mississauga, ON
Posts: 1,163
scanny will become famous soon enough
scanny scanny is offline
Senior Member
scanny's Avatar
 
Join Date: Aug 2010
Location: Mississauga, ON
Posts: 1,163
scanny will become famous soon enough
I'm going to offer a good solution for the LT tire pressure. Instead of arguing abut this just look in the manual. It clearly says how to determine maximum load for a tire. Basically you'll need to check door sticker for Gross Axle Weight Ratings (there is two for front and rear axle) and pick one whichever is greater. Then you divide this number by two and now you know your maximum load of tire. Then you find your tire in the LT tire load table and see the correct maximum pressure. No guesses, confusion or arguments.
__________________
2022 4Runner TRD Off Road, Lunar Rock
Goodyear Wrangler Duratracs
scanny is offline   Reply With QuoteReply With Quote
Old 07-30-2013, 10:24 AM #26
Canazes9's Avatar
Canazes9 Canazes9 is offline
Member
 
Join Date: Jun 2013
Location: Texas
Posts: 942
Real Name: David
Canazes9 is on a distinguished road
Canazes9 Canazes9 is offline
Member
Canazes9's Avatar
 
Join Date: Jun 2013
Location: Texas
Posts: 942
Real Name: David
Canazes9 is on a distinguished road
Quote:
Originally Posted by scanny View Post
I'm going to offer a good solution for the LT tire pressure. Instead of arguing abut this just look in the manual. It clearly says how to determine maximum load for a tire. Basically you'll need to check door sticker for Gross Axle Weight Ratings (there is two for front and rear axle) and pick one whichever is greater. Then you divide this number by two and now you know your maximum load of tire. Then you find your tire in the LT tire load table and see the correct maximum pressure. No guesses, confusion or arguments.
Scanny,

That will give you your correct minimum pressure, not maximum right?

For stock sized LT tires on the 5th gen 265/70R17 the min pressure is 35psi. That is the min acceptable for an LT tire, will give 7500 GVWR, 3,750 per axle. But there are other reasons to increase tire pressure beyond min load specifications. Increased tire pressure may give increased gas mileage, improved on road handling characteristics which are to be balanced w/ passenger comfort and tire wear characteristics.

The min pressure for the P metric tires is 26 psi which yields GVWR capacity of 8,000 pounds, 4,000 per axle. Again, this meets the minimum necessary to be within the design parameters for this vehicle and tire combination. Toyota recommends tire pressure of 32, not the min of 26 to increase performance in other areas beyond load carrying capacity. Presumably the additional pressure increases gas mileage, provides enhanced on road handling and tire wear characteristics while providing an acceptable compromise in ride comfort.

A good starting point to provide optimum mileage/road handling would be a similar percentage increase from min in the LT tires as the percentage increase in min over P metric tires. 32/26 = 123% over min. 35x 123% = 43psi. That is the equivalent psi in the LT tires.

The problem with that is that LT tires have much stiffer carcasses and side walls than P metric tires and as such don't require as much air pressure increase over min to achieve optimum mileage, on road handling and wear benefits. The optimum is likely be somewhere in between 35 and 43 psi and you will have to determine what feels best for your particular tire/load combination. I suspect that in instances where the same LT tire is offered in both a D and an E rated tire, the E rated tire will require a slightly lower optimal pressure (maybe 1-2psi?).

Thoughts?

David
Canazes9 is offline   Reply With QuoteReply With Quote
Old 07-30-2013, 11:52 AM #27
eddiebx's Avatar
eddiebx eddiebx is offline
Senior Member
 
Join Date: Aug 2012
Location: My Computer
Posts: 3,113
eddiebx will become famous soon enough eddiebx will become famous soon enough
eddiebx eddiebx is offline
Senior Member
eddiebx's Avatar
 
Join Date: Aug 2012
Location: My Computer
Posts: 3,113
eddiebx will become famous soon enough eddiebx will become famous soon enough
Quote:
Originally Posted by JB. View Post
I love easy experiments that bring real evidence to endless discussion. I perform them whenever possible. Unfortunately, I don't own P tires but otherwise I'd be happy to run them at 25psi for a while (with due caution). I'm sure cornering would be less stable and mpg would suffer, but what else is it you imagine would happen?
Due to my own negligence I've done this before for ~750 mile long road trip. I did not find anything wrong besides the outer edges of the tires wearing off a bit more than the center. I actually didn't even notice any significant difference in handling throughout the drive and only found out after I got back from my trip and checked my tire pressure (which was in the low 20s). And yes if you are wondering, now I check my pressure before I leave for a road trip instead, lol.
eddiebx is offline   Reply With QuoteReply With Quote
Old 07-30-2013, 12:36 PM #28
scanny's Avatar
scanny scanny is offline
Senior Member
 
Join Date: Aug 2010
Location: Mississauga, ON
Posts: 1,163
scanny will become famous soon enough
scanny scanny is offline
Senior Member
scanny's Avatar
 
Join Date: Aug 2010
Location: Mississauga, ON
Posts: 1,163
scanny will become famous soon enough
Quote:
Originally Posted by Canazes9 View Post
Scanny,

That will give you your correct minimum pressure, not maximum right?

David

Well it depends on point of view, from Toyota (truck) point of view, minimum tire pressure are for not loaded truck, and maximum is for fully loaded truck. You don't have to go any higher than that.

From tire and people point of view tire maximum pressure is written on tires.

a little bit mix up in terms , so let's say that our truck requires 35 psi to support fully loaded axles. Then you can set any pressure higher than 35 psi up to tire max pressure limit.

In my experience when I run tires at 44psi they were running quieter and provided better fuel economy but they started wearing more in center and outer side weren't fully touching the pavement which might be not a good thing in slippery conditions.

I did "chalk test" at 44 psi, sort of - I was driving on gravel road and was shocked that at 44 psi about an inch of each side of outer side lugs was black when tire in centre was grey from dust. Same thing in the winter when you drive over salt you can see how much of your tire is actually touching the pavement. So as long as you have full contact you're good to run over required pressure, otherwise you're promote uneven wear and reduce tire grip. But if fuel efficiency and less noise is more important maybe it's not such a bad thing.
__________________
2022 4Runner TRD Off Road, Lunar Rock
Goodyear Wrangler Duratracs

Last edited by scanny; 07-30-2013 at 12:46 PM.
scanny is offline   Reply With QuoteReply With Quote
Old 07-30-2013, 01:28 PM #29
Canazes9's Avatar
Canazes9 Canazes9 is offline
Member
 
Join Date: Jun 2013
Location: Texas
Posts: 942
Real Name: David
Canazes9 is on a distinguished road
Canazes9 Canazes9 is offline
Member
Canazes9's Avatar
 
Join Date: Jun 2013
Location: Texas
Posts: 942
Real Name: David
Canazes9 is on a distinguished road
Quote:
Originally Posted by scanny View Post
Well it depends on point of view, from Toyota (truck) point of view, minimum tire pressure are for not loaded truck, and maximum is for fully loaded truck. You don't have to go any higher than that.

From tire and people point of view tire maximum pressure is written on tires.

a little bit mix up in terms , so let's say that our truck requires 35 psi to support fully loaded axles. Then you can set any pressure higher than 35 psi up to tire max pressure limit.

In my experience when I run tires at 44psi they were running quieter and provided better fuel economy but they started wearing more in center and outer side weren't fully touching the pavement which might be not a good thing in slippery conditions.

I did "chalk test" at 44 psi, sort of - I was driving on gravel road and was shocked that at 44 psi about an inch of each side of outer side lugs was black when tire in centre was grey from dust. Same thing in the winter when you drive over salt you can see how much of your tire is actually touching the pavement. So as long as you have full contact you're good to run over required pressure, otherwise you're promote uneven wear and reduce tire grip. But if fuel efficiency and less noise is more important maybe it's not such a bad thing.
That's pretty much what I've seen on my Tacoma - 38psi w E rated seems to be optimum. Don't have tires for the T4R yet, but will soon...

David
Canazes9 is offline   Reply With QuoteReply With Quote
Old 07-30-2013, 04:42 PM #30
JB.'s Avatar
JB. JB. is offline
Senior Member
 
Join Date: Dec 2004
Location: So. Nevada
Posts: 3,161
JB. will become famous soon enough
JB. JB. is offline
Senior Member
JB.'s Avatar
 
Join Date: Dec 2004
Location: So. Nevada
Posts: 3,161
JB. will become famous soon enough
Quote:
Originally Posted by scanny View Post
I'm going to offer a good solution for the LT tire pressure. Instead of arguing abut this just look in the manual. It clearly says how to determine maximum load for a tire. Basically you'll need to check door sticker for Gross Axle Weight Ratings (there is two for front and rear axle) and pick one whichever is greater. Then you divide this number by two and now you know your maximum load of tire. Then you find your tire in the LT tire load table and see the correct maximum pressure. No guesses, confusion or arguments.
That could be a problem because it, too, requires reading.

But this thread isn't really about any "solution" to LT tire pressure because there is no single answer. However, for set and forget simplicity, it's hard to go wrong with simply matching factory load reserve.

This thread was simply intended to make known a non-intuitive fact about the load carrying differences between P and LT tires. Since it's a non-intuitive fact that has been shown over time to not stick easily, I attempted to make it easier by making it visual.

What people do with the information is a separate subject, but it's information worth knowing.
__________________
2005 Limited V8
Bilstein 5100 at .85
5th gen SR5 springs
BFG AT KO2 LT265/70/17 Load C (Replaced Revo 2 LT265/70/17 Load E)
Hanna sliders
JB. is offline   Reply With QuoteReply With Quote
Reply

Tags
light truck , load range , load rating , passenger , ply rating

Thread Tools
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
What tire pressure do you run in your stock size tires??? Jeff T 4th Gen T4Rs 2 07-27-2011 08:00 AM
What Tire Pressure do you run on your Stock Tires? New03formeh Polls 4 06-25-2008 09:29 AM
Got new tires and low pressure warning light will not go out arouth 4th Gen T4Rs 29 11-14-2006 06:23 AM
Tires pressure desertrat Classic T4Rs 3 06-12-2006 04:13 PM
New tires and tire pressure system issues Duc Hunter 4th Gen T4Rs 4 05-25-2005 03:11 AM

Powered by vBadvanced CMPS v3.2.2

All times are GMT -4. The time now is 05:11 AM.

Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2024 DragonByte Technologies Ltd.
Feedback Buttons provided by Advanced Post Thanks / Like (Lite) - vBulletin Mods & Addons Copyright © 2024 DragonByte Technologies Ltd.
User Alert System provided by Advanced User Tagging (Lite) - vBulletin Mods & Addons Copyright © 2024 DragonByte Technologies Ltd.
***This site is an unofficial Toyota site, and is not officially endorsed, supported, authorized by or affiliated with Toyota. All company, product, or service names references in this web site are used for identification purposes only and may be trademarks of their respective owners. The Toyota name, marks, designs and logos, as well as Toyota model names, are registered trademarks of Toyota Motor Corporation***Ad Management plugin by RedTyger
 
Copyright © 2020