2nd Gen Non-Engine/Transmission What defines a load range E tire?

[CoastyAV8R]

I am looking at replacing the stock Michelin's on my truck after over 50,000 miles of service. I would like to get a 285 or 295 tire but I haven't found any in load range E. What's interesting is, for example, a 295/75 Nitto Terra grappler has the same max load weight rating as the stock E range 265 Michelin's, 3415 lbs. The only difference is the Michelin's do it with 80 psi and the Nitto with 65 psi. However the Nitto is a "D" rated tire and the michelin is an "E" rated tire, what gives. I haul our 5th wheel so the load rating is important to me, I don't need a blow out...

Any ideas?



Thanks,

Pat

 

[RustyJC]

Load Range comparisons are only valid within a specific size tire. For instance, all Load Range E tires in an LT235/85R-16 are 3042 lbs @ 80 PSIG in single wheel service. The same size tire in a Load Range D is rated at 2623 lbs @ 65 PSIG. As you have found, you can often get the same or higher actual load carrying capacity by going to a larger tire with a lower Load Range rating.



What's standard about Load Range ratings is the inflation pressures at which the ratings are made. For instance:



Load Range C - 50 PSIG

Load Range D - 65 PSIG

Load Range E - 80 PSIG

Load Range G - 110 PSIG



Hope this helps some. Click on the Load/Inflation Information Tables at the top of this page for some examples.



Rusty

 

[CoastyAV8R]

Thanks Rusty. So in theory I could use the larger D range tire and not have to worry about over loading the tire since it has the same weight bearing capacity, right?

 

[RustyJC]

Originally posted by CoastyAV8R

So in theory I could use the larger D range tire and not have to worry about over loading the tire since it has the same weight bearing capacity, right?

Yes, that's correct. That's not to say you may not have issues with more sway, etc. due to the taller sidewall and lower inflation pressure of the larger tire, but the larger D-rated tire is rated by the manufacturer as being capable of carrying the maximum load stamped on the sidewall - which may be higher than the maximum load stamped on the side of a smaller E-rated tire.



Rusty

 

[CoastyAV8R]

Thanks again Rusty. From what I have seen, you seem to be a never ending source of info...

 

[fkovalski]

tire ratings

Here's a thread from a short while ago with similar questions you are asking: tire ratings

 

[Cooker]

Originally posted by RustyJC

That's not to say you may not have issues with more sway, etc. due to the taller sidewall and lower inflation pressure of the larger tire

This statement is right on. If towing heavy loads is the primary use of the truck, an E tire is a safer bet than a D tire even though the load rating may be the same.

 

[GFoley]

285 or 295 tires are a lot wider and are able to spread the load over a greater contact patch.



Remember stories about elephants being allowed on gym floors but women wearing pointy high heels were not? Same principle.



My 255/85 BFG M/Ts are LR D tires, rated 3,000# at 65psi. I just had a blow out on the RF and have gone back to 245/75s. I also think that you'll find heavier construction in the LR E tires.



GLF

 

[Rams-n-Hogs]

There is a difference in the construction of the tires. A D rated tire is an 8-ply tire, while an E rated tire is 10. I personally wouldn't haul my 5th wheel on a D rated tire, even though the load range might be capable. Aside from allowing the extra air pressure, those 2 extra plies help strengthen and stiffen the sidewall, which increases stability. JMO.



Jim

 

[NScott]

If you NEED a really high load range (going to carry a LOT of weight) , don't mess around with 235/85 or any size of those load range E tires. Go get a set of 7. 50R/16 14 ply rating (load range G) I got a set of Kuhmos and they are great! I don't worry about a blowout anymore. These will stand more weight than the axle/truck can take IMO. These are supposed to be used on trailers/lowboys, but they are regrooveable like road tractor tires, they are radial,but they require a tube. They have a nice looking street tread.

 

[WestTN]

one more view...

The load a tire will support is determined by 2 things: the contact patch area multiplied by the tire pressure. A larger size tire has a larger contact area, so, for a given pressure it will support a larger load.



The load range is determined by the construction of the tire: the more air pressure the tire can contain, the more load it can carry, hence the larger tire you mentioned can carry the same load as the smaller, but higher pressure rated tire. The load range, and subsequently the allowable inflation pressure, is determined by the construction of the tire. Tireswillgenerally state ' x ply rated'. There may actually be fewer plies of some stronger material.



The big thing to keep in mind here is that the rim also has a maximum inflation pressure rating. And there is a narrow range of tire sizes that will properly fit on a given rim. Wider tires than suited for your rims will give increased sway and tire wear.

Assuming the larger tire is inflated to the correct pressure for the load, there should be no more sway than with a smaller tire at a higher but still adequate pressure. The aspect ratio has more of a bearing here. And remember, the tire does not support the load. The tire only contains the compressed air and the air supports the load.

 

[RustyJC]

Re: one more view...

Originally posted by WestTN

Assuming the larger tire is inflated to the correct pressure for the load, there should be no more sway than with a smaller tire at a higher but still adequate pressure. The aspect ratio has more of a bearing here.

Dennis,



With all respect, I'm going to challenge you on this statement. A shorter sidewall (actual measurement) at 80 PSIG on a smaller E-rated tire (higher ply rating hints at possibly stiffer construction) will flex less than the taller, possibly thinner sidewall at 65 PSIG on a larger D-rated tire of the same aspect ratio. I believe we have enough case history over at iRV2.com among those who tow heavy 5th wheels to bear this out.



Rusty

 

[Rams-n-Hogs]

I have to agree with Rusty on this one. Not to mention, if the air supports the load, 80PSI will support better than 65PSI regardless of what it's housed in. I would also think it would help eliminate sway due to the higher pressure. Have you ever tried to push in the sidewall of an E-rated tire at 80PSI, and done the same thing to a D-rated tire at 65PSI? The E is like a rock, whereas the D has a little more give to it. That suggests to me, the D will flex more.



Jim

 

[OTRPU]

NScott, you've got me curious now. I've been living under the gross misconception that there is a difference tween Steers and Drive tires. Your suggestion seems to ignore this fact. More dialogue requested.



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Side note: as you can all plainly see, I figured out how to insert photos in the message, not much luck with doing same in my profile at the bottom yet. Any help would be appreciated.



Safe Towing,

Steve J.

 

[NScott]

The Kuhmos I bought were put only on the rear axle of my C&C 3500 2WD. As I stated, the are 7. 50R-16. I don't recall the tire model number, I have it written down at my shop and I will post it later. ( as an edit) The tires have a good looking "street" or highway type tread. They have STIFF sidewalls and were built to carry WEIGHT! For serious hauling, I wouldn't ever consider anything else other than this size/spec for our trucks with the 16" rims. I run Michilen 215/85R16 Load range E on the steering axle. The profile of the 7. 50R-16's is just a little taller than the 215/85R16's. As I have stated, I don't worry about blowouts anymore, just overloading the truck and AXLE with more than it will take or pull SAFELY!



99 C&C 3500 5spd 2wd, Dynosourses box,elbow & module, 4" straight from the turbo out,triple piller,stock injectors(soon to change), 14cm wastegated turbo housing.

 

[WadePatton]

about PLY ratings

I was recently informed by a tire shop owner that the ply-rating is just that. Way back when a tire had 4 or 10 or 14 plys. Now they all generally have the same number of belts, but the higher load ratings result from heavier construction of the belts.



At least that's what he said. Makes sense to me as the number of belts on my "10-ply" tire don't add up.