Non LT Tyres(Tires)

[Ghost Who Walks]

This is going to open up a can of worms(And I have my flame suit on)
I live in Australia( and I'm guessing that this rings true in the USA etc), but why does it seem that you "Have" to run LT tyres(Tires) when your out touring/4wding?
Currently, I am running some LT tyres, and yes, they are still quiet after 85000km(52000 Miles) with about another 15000km left in them, But I have been wondering what's with the fixation of using LT at all times?
Before LT where commonly available, I'm guessing the normal P rater AT etc tyres(Tires) where used, and to great effect to open up the country.
Is there anything wrong with using non LT tyres(Tires) for touring/expedition?

Flame suit at the ready

 

[rruff]

ATs are generally more durable and have better traction, but... lighter duty tires worked fine for me. I put a lot (probably near 100k) of dirt and rocky trial miles on a Toyota PU for 13 years and always had cheap standard duty tires. Very few flats and was never stranded.

 

[85_Ranger4x4]

Before AT tires there were 8 plys or 10 plys, heavier tires are nothing new.

I don't even overland really, gravel roads murder P rated tires though. I just run 6 ply though so they are on the lighter end and get along fine with my Ford F-150 and Ford Ranger.

My wife has P rated Destination LE's on her Ford Edge and I think she is on her fourth low tire light of the year for picking up something on gravel. I have had one between my two trucks and it was a nasty nail I picked up on my grandfather's farm.

The little WWII army Jeep had 6ply tires...

 

[Betarocker]

AT tires come in both Passenger and Light Truck versions in some sizes, with substantial differences in capacity.

That WW2 Jeep could be lifted by 1/2 dozen fit soldiers; a current 1/2 ton would require the whole platoon.

 

[tacollie]

I run LT tires because I got tired of plugging sidewalls. I tried running p rated tires on my lightweight Toyotas twice and both times my patch kit got extensive use. Tire treads offered in both p and LT ratings often have a different tread depth. So the LT tires will last longer.

 

[broncobowsher]

A lot of it is "bigger is better" mentality, even if not.

But there is some truth in the higher payload capacity, as so many overload and don't even know it.

 

[billiebob]

Before LTs and P-Metric we had Bias Ply with 4/6/8/10 plys. I think there were 2ply tires too for things like the Isetta and CV2.
Then we finally got radials with thin sidewalls for a comfortable street ride. Guys like Dyck Cepek met the desire/need for flotation tires in the light truck, 4WD community replacing the old commercial 6/8/10 ply tires. Initially they were all bias ply. Today the LT Radials are excellent tires.

You can run whatever ya want but LT tyres are still the popular choice when you need a tougher sidewall. And the smaller commercial truck tires like 235/85R16s are an excellent buy, often delivering up to 50% more tread life than the LT Floatation Tire sizes.... and less expensive too.

 

[Grassland]

Really depends how heavy the vehicle is I'd say. I run LT because the sizes I want come in LT ratings, and I want a beefier sidewall.
I've had zero flats in my F150 on LT235/80R17 and LT34x10.5R17 KO2s, but had two flats on my 235/65R16C Euro metric "commercial" capacity tires on my Transit, so I imagine it's more tire construction design than load rating in regards to flats.
Will be trying to stick with P rated for my wife's WK2 because it's primarily used as a city commuter and I want to keep the rolling mass down.

 

[85_Ranger4x4]

AT tires come in both Passenger and Light Truck versions in some sizes, with substantial differences in capacity.

That WW2 Jeep could be lifted by 1/2 dozen fit soldiers; a current 1/2 ton would require the whole platoon.

I was thinking LT but typed AT for reasons unknown.

And exactly, that little bugger had 6 plys but you think you can get by with 4plys on your half ton?

 

[Mighty Dodge Ram]

Load ratings. Max PSI on my wife’s P-metric Michelins tops out at 41#. That’s fine (barely) for the kind of road trips we take. Anything heavier would require an LT LR-D max PSI 65# or LR-E like the ones I run on the truck…max PSI 80#.

 

[XJLI]

I think a lot of people are out there running E loads for literally no reason at all other than to say they are. Are the sidewalls stronger? In a load carrying sense, yes. In a puncture resistance sense? Not necessarily. I'm running XL rated tires on my truck (it's heavy, and that's what it came with from the factory) but P rated tires are more than adequate for most people. Also, E rated tires are heavy, and will suck fuel if you don't need the load carrying. Most 1500s come from the factory with P rated tires, and they are completely fine to be used up to GVWR and GVCR. If you have a 4Runner with 1500lbs of bumpers/armor/rotopax and then 2 people and a German Shepard... well, you'll probably over the load rating of the factory rubber.

A P rated Toyo AT3 is going to have more puncture resistance than an E rated highway rib tire. I flatted and sliced E rated tires in situations where I don't think the tire should have failed, and have beat on C rated tires and couldn't believe they weren't ripping in two. It's more about tire construction (like a previous poster replied earlier). If the tire manufacturer intends the tire to be used off-road (3 ply sidewall or whatever marketing jargon), that's the tire you want to use in off road situations. There are exceptions, like noted in another thread about the Michelin Defenders.

 

[jbaucom]

I think a lot of people are out there running E loads for literally no reason at all other than to say they are. Are the sidewalls stronger? In a load carrying sense, yes. In a puncture resistance sense? Not necessarily. I'm running XL rated tires on my truck (it's heavy, and that's what it came with from the factory) but P rated tires are more than adequate for most people. Also, E rated tires are heavy, and will suck fuel if you don't need the load carrying. Most 1500s come from the factory with P rated tires, and they are completely fine to be used up to GVWR and GVCR. If you have a 4Runner with 1500lbs of bumpers/armor/rotopax and then 2 people and a German Shepard... well, you'll probably over the load rating of the factory rubber.

Many people are running LRE tires because LRC & LRD are going the way of the dodo in many tire lines, if you don't want a P-metric replacement for the factory size, then your LT-metric option is load range E. Exceptions to this are largely OE fitments, or built by dedicated off-road tire makers. There is much greater demand for P-metric and LRE tires. Traditionally, LRC was used on 1/4T & 1/2T vehicles, and most of these are now equipped with P-metric or E-metric tires from the factory. In the event that a vehicle does spec a LRC tire (or LRD), a LRE tire will exceed the spec and therefore is suitable for installation. At the same pressure, a LRC & LRE tire are rated to carry the same load; the difference is that a LRC tire has a maximum inflation pressure of 50 PSI, and that's where its carrying capacity ends on a load/inflation table. If a vehicle specs a P-metric or E-metric tire, then that tire is perfectly adequate when used as the vehicle is designed and up to the mfg. GVWR. However, adequate is not the same as ideal. I prefer LT tires for the deeper tread depth (generally 30-50% more usable tread depth than a P-metric). In my experience, there is little ride quality difference between a p-metric tire and an LT that is run at the proper pressure for the load (unless we're talking about 20"+ wheels). Many people are running around with their tire pressure too high in LT tires, especially on 1/2T and lighter trucks and SUVs, because they think the max pressure shown on the sidewall is what the tire should be inflated to (and they've never heard of a load/inflation table, or don't know how to use it).

 

[XJLI]

Yea, its definitely slimmer pickings for tires now. Most wheels are 18s or 20s, and like you said at that point it just makes sense to make OE-spec and then right to LR E (even F!). Its hard to even find certain sizes/specs in 17" flavor.

 

[deserteagle56]

I live in the middle of Nevada - not much in the way of pavement around here. If I leave my driveway and head south it is 133 miles to the first paved road. My experience has been that P-rated tire cannot hold up to driving dirt roads at speeds. I - and everyone I know around here - run E-rated LT tires on all our rigs. The more plies in the tread area the better the tire will resist rock breaks through the tread. First thing all the mines around here do when they buy a new truck is to install Toyo Open Country M/T tires on them because they have 7 full plies in the tread area and hold up the best to off-highway driving.

Not a good place to be driving on P-rated tires:


The other thing to remember when driving dirt roads is to air down. I believe it was Cooper tires that had a video showing the difference in puncture resistance in a tire that is aired down versus one that is at high psi. Just because a tire has 50 psi or 80 psi as max pressure on the sidewall doesn't mean that's what the tire should be inflated to when driving a dirt road!