Perfect off-highway tire = LTX? What?

Jack90210

New member
So, for LTXs on an '07 LX470 that will see very little offroad (I have KO2s for that) but some moderate (3000-ish pounds) towing, what's the consensus on P vs LT? I've had E-rated LTs before (Goodyear SilentArmor) which IMO rode "reassuringly firmly" at 40-45 psi, and seemed to do very well when loaded down in the summer on a hot highway (unlike some tires that have made me wonder when I pull over and feel the sidewall, man, are these things gonna burn up?).

I don't want to pay a weight penalty that I don't need to pay, but I also don't like a squishy-feeling ride on the highway. Happy to hear opinions; thank you in advance.
 
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XJLI

Adventurer
So, for LTXs on an '07 LX470 that will see very little offroad (I have KO2s for that) but some moderate (3000-ish pounds) towing, what's the consensus on P vs LT? I've had E-rated LTs before (Goodyear SilentArmor) which IMO rode "reassuringly firmly" at 40-45 psi, and seemed to do very well when loaded down in the summer on a hot highway (unlike some tires that have made me wonder when I pull over and feel the sidewall, man, are these things gonna burn up?).

I don't want to pay a weight penalty that I don't need to pay, but I also don't like a squishy-feeling ride on the highway. Happy to hear opinions; thank you in advance.
The LX470 was tested and engineered to carry its listed payload and tow to capacity using the tires it came on from the factory, which are P-rated. Those are the ones you should run.
 

Regcabguy

Expedition Leader
I'd err on the side of too much tire. The E's can always be deflated a bit to improve the ride. With the P's your stuck. That Lexus is a heavy vehicle and combined with towing I'd feel more comfortable with an E or perhaps a D. I don't know how the full size 1/2 ton trucks get away with passenger tires on light trucks.
 

80t0ylc

Hill & Gully Rider
I'd err on the side of too much tire. The E's can always be deflated a bit to improve the ride. With the P's your stuck. That Lexus is a heavy vehicle and combined with towing I'd feel more comfortable with an E or perhaps a D. I don't know how the full size 1/2 ton trucks get away with passenger tires on light trucks.
Agreed. What do you get if you err on the side of too much tire? Maybe spend a little more $ than you needed to, but usually a satisfied customer. What do you get when you err on the side of too little tire? If you're lucky, premature wear or failure ..... but if you're unlucky, a disaster for you and possibly others.
 

(none)

Adventurer
I'd err on the side of too much tire. The E's can always be deflated a bit to improve the ride. With the P's your stuck. That Lexus is a heavy vehicle and combined with towing I'd feel more comfortable with an E or perhaps a D. I don't know how the full size 1/2 ton trucks get away with passenger tires on light trucks.
What do you mean you do know how full size trucks get away with p-tires? That's easy, because they are rated for more than the max load of the vehicle. A 275/70R16 Michelin LTX has a capacity of 2601lbs and weighs 38lbs. That gives you over 10k capacity at full pressure. The LX470 for instance has a GVWR of under 6900 lbs. No where in the realm of being near capacity.

A 275/65r18 which is a common size OEM Ram 1500 tire has a rating of 2756lbs. Highest GVWR for a Ram, F150 or Chevy 1500 is 7800lbs (Ram). Once again, nowhere near the max of the tire.

Agreed. What do you get if you err on the side of too much tire? Maybe spend a little more $ than you needed to, but usually a satisfied customer. What do you get when you err on the side of too little tire? If you're lucky, premature wear or failure ..... but if you're unlucky, a disaster for you and possibly others.
Satisfied customer of having an unnecessarily harsh ride, even worse fuel mileage and increased wear on suspension components? What disaster for using tires properly rated for a vehicle? He's not asking about how to fit p-tires on a one ton towing construction equipment.

There is absolutely no reason to go with an LT tire just people think it'll help with safety. A p-rated tire on an LX is just fine. If you want an LT because you want KO2s or another tire that only comes in LT ratings, fine. I'd still go with the lightest one possible that meets the minimum ratings at least.
 

80t0ylc

Hill & Gully Rider
Satisfied customer of having an unnecessarily harsh ride, even worse fuel mileage and increased wear on suspension components? What disaster for using tires properly rated for a vehicle? He's not asking about how to fit p-tires on a one ton towing construction equipment.

There is absolutely no reason to go with an LT tire just people think it'll help with safety. A p-rated tire on an LX is just fine. If you want an LT because you want KO2s or another tire that only comes in LT ratings, fine. I'd still go with the lightest one possible that meets the minimum ratings at least.
Living where you live, maybe you're not aware that 'P' rated tires are not designed to be aired down for off road duty. When 'P' rated are mistakenly aired down and run for very long, their sidewalls will suffer undetectable damage that can only be seen by failure or if removed from their rim before a failure. And maybe you shouldn't be giving advice when you don't know what you're talking about and don't have the experience to understand why people air down off road with LT rated tires. And maybe you should keep to paved roads where you can have the smooth ride and get the best fuel mileage with your 'P' rated tires. BTW, my Land Cruiser 80's suspension holds up just fine to LT tires, and always will.
 

(none)

Adventurer
So, for LTXs on an '07 LX470 that will see very little offroad (I have KO2s for that) but some moderate (3000-ish pounds) towing, what's the consensus on P vs LT? I've had E-rated LTs before (Goodyear SilentArmor) which IMO rode "reassuringly firmly" at 40-45 psi, and seemed to do very well when loaded down in the summer on a hot highway (unlike some tires that have made me wonder when I pull over and feel the sidewall, man, are these things gonna burn up?).

I don't want to pay a weight penalty that I don't need to pay, but I also don't like a squishy-feeling ride on the highway. Happy to hear opinions; thank you in advance.

Living where you live, maybe you're not aware that 'P' rated tires are not designed to be aired down for off road duty. When 'P' rated are mistakenly aired down and run for very long, their sidewalls will suffer undetectable damage that can only be seen by failure or if removed from their rim before a failure. And maybe you shouldn't be giving advice when you don't know what you're talking about and don't have the experience to understand why people air down off road with LT rated tires. And maybe you should keep to paved roads where you can have the smooth ride and get the best fuel mileage with your 'P' rated tires. BTW, my Land Cruiser 80's suspension holds up just fine to LT tires, and always will.
Well... lets see... They are asking for an on-road tire that will see very little use offroad, in fact they have other tires other tires for that.

I had no issues with LT tires on my 80 series either. Same as i don't on my Frontier. But they both ended up with decreased fuel mileage and more noise. I wheeled all over Colorado, Tennesse, Georgia, and the Carolinas on stock P tires without issues. In fact, the only tire i have ever punctured on a trail was an LT d-rated tire on the 80.
 

80t0ylc

Hill & Gully Rider
Well... lets see... They are asking for an on-road tire that will see very little use offroad, in fact they have other tires other tires for that.

I had no issues with LT tires on my 80 series either. Same as i don't on my Frontier. But they both ended up with decreased fuel mileage and more noise. I wheeled all over Colorado, Tennesse, Georgia, and the Carolinas on stock P tires without issues. In fact, the only tire i have ever punctured on a trail was an LT d-rated tire on the 80.
My point is, if you're running off road and airing down, you'd best be running LT tires. You can brag and celebrate all you wish for what you're getting away with, but I'm just trying to pass on knowledge and people can do what they want with it.
 

jbaucom

Well-known member
What do you mean you do know how full size trucks get away with p-tires? That's easy, because they are rated for more than the max load of the vehicle. A 275/70R16 Michelin LTX has a capacity of 2601lbs and weighs 38lbs. That gives you over 10k capacity at full pressure. The LX470 for instance has a GVWR of under 6900 lbs. No where in the realm of being near capacity.

A 275/65r18 which is a common size OEM Ram 1500 tire has a rating of 2756lbs. Highest GVWR for a Ram, F150 or Chevy 1500 is 7800lbs (Ram). Once again, nowhere near the max of the tire.



Satisfied customer of having an unnecessarily harsh ride, even worse fuel mileage and increased wear on suspension components? What disaster for using tires properly rated for a vehicle? He's not asking about how to fit p-tires on a one ton towing construction equipment.

There is absolutely no reason to go with an LT tire just people think it'll help with safety. A p-rated tire on an LX is just fine. If you want an LT because you want KO2s or another tire that only comes in LT ratings, fine. I'd still go with the lightest one possible that meets the minimum ratings at least.
You are failing to mention that p-metric tires installed on light trucks/SUVs are de-rated by ~9%. The load index is still sufficient for safety on the vehicles that include p-metric OEM tires, but those LTXs that you reference for an LX470 do not quite provide 9500 lbs of capacity - well short of "over 10k capacity at full pressure." IME, an LT-metric tire of similar tread pattern and at an appropriate pressure according to a tire load/inflation table neither rides noticeably worse or gets noticeably worse fuel economy than a properly inflated p-metric tire of the same/similar tread (i.e. mild a/t, LTX M/S2, A/S, etc).

Edited to add: Tire weight is an important factor in ride quality since OE suspensions are tuned for a certain range of unsprung weight. Most of us run 17"-18" wheels on our vehicles, and these vehicles often offer 20"+ wheel packages which are significantly heavier than the smaller wheel offerings. With a 17" or 18" wheel you can often step up to a light LT-metric tire like a GY A/T Adventure, Bridgestone Revo 3, or FS Destination X/T while staying pretty close to the weight of a factory 20" wheel assembly. My 2014 GMC came with OE 17" wheels and 36 lb tires - the whole assembly weighed 63 lbs. The same truck offered 22" wheels that weighed up to 92 lbs with factory tires. The common 20" wheel assemblies weighed nearly 80 lbs with OE tires. I could easily step up to a 55-60 lb tire while still remaining within the weight range of OE options.
 
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S_Kolb

New member
Living where you live, maybe you're not aware that 'P' rated tires are not designed to be aired down for off road duty. When 'P' rated are mistakenly aired down and run for very long, their sidewalls will suffer undetectable damage that can only be seen by failure or if removed from their rim before a failure. And maybe you shouldn't be giving advice when you don't know what you're talking about and don't have the experience to understand why people air down off road with LT rated tires.
If you've found any info on the performance of P vs LT rated tires when aired down, please share it! I've not seen any manufacturer data on aired-down performance– manufacturers seem reluctant to endorse or even acknowledge the practice.
In tires of the same size at the same load, LT tires typically require higher pressure than P rated tires, because there's less internal air volume. It's far from obvious to me that LT would be generally better than P at low pressure.
 

pskhaat

2005 Expedition Trophy Champion
...those LTXs that you reference for an LX470 do not quite provide 9500 lbs of capacity - well short of "over 10k capacity at full pressure." IME, an LT-metric tire...
To bring this back to the thread topic (kinda), the LTX would always be LT on Cruiser sizes, no?
 

jbaucom

Well-known member
To bring this back to the thread topic (kinda), the LTX would always be LT on Cruiser sizes, no?
No, not necessarily. I checked a 1995, 2005, and 2015 Land Cruiser, and none of them spec LT-metric tires as the stock size. There are plenty of plus-size options for LCs that are P-metric or Euro-metric, and they are often XL rated.
 

80t0ylc

Hill & Gully Rider
If you've found any info on the performance of P vs LT rated tires when aired down, please share it! I've not seen any manufacturer data on aired-down performance– manufacturers seem reluctant to endorse or even acknowledge the practice.
In tires of the same size at the same load, LT tires typically require higher pressure than P rated tires, because there's less internal air volume. It's far from obvious to me that LT would be generally better than P at low pressure.
I see what you mean, after some web searching. Plenty agreement on forums, but that's not info many tire makers share willingly. My post was made from personal experience and advice given by "tire techs" at tire shops who've seen the damage. It's common sense that stronger sidewalls hold up better to the abuse of a tire. And to be honest, it is tire abuse to air tires down for the "means to an end" (better traction, better flotation, more comfortable ride on washboard...etc). It works for us, but I can see why tire manufacturers don't condone the practice. I guess if asked for my opinion, I'd say if you're traveling off road, get the stoutest tires, especially the sidewalls, you can live with.
 

XJLI

Adventurer
I see what you mean, after some web searching. Plenty agreement on forums, but that's not info many tire makers share willingly. My post was made from personal experience and advice given by "tire techs" at tire shops who've seen the damage. It's common sense that stronger sidewalls hold up better to the abuse of a tire. And to be honest, it is tire abuse to air tires down for the "means to an end" (better traction, better flotation, more comfortable ride on washboard...etc). It works for us, but I can see why tire manufacturers don't condone the practice. I guess if asked for my opinion, I'd say if you're traveling off road, get the stoutest tires, especially the sidewalls, you can live with.
I've had the manufacture tell me the opposite. I ran load range E Cooper AT3s, and got a sidewall puncture in two of them. Once was aired down to ~18 or so PSI, once at street pressure ~30 PSI. I contacted Cooper about it, and this was the response, " Given the information you have provided, you may want to consider either the Discoverer S/Tmaxx or Discoverer STT as both of these tires have a 3-ply sidewall."

When it comes to airing down, puncture/chip resistance, etc; the actual tire construction, and the brand's investment into off-roading and the hobby > whatever the numbers and labels are on the sidewall. Doesn't matter the load range. I will only run Michelins, BFGs, or Toyos on any car or truck.
 

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