Tire Load Rating - Size Question

[BHolm]

To each his own I guess. I have run the larger sized D tires on work trucks right along side work trucks pulling the same trailers wearing E rated tires. You must have a sensitive tushy as I, nor any of the professional drivers I employed ever found the trucks wearing D rated tires any more or less stable than the trucks fitted with E's. On many occasions I have pulled big loads cross country and through the mountains on D rated tires. The last trip was 1400 miles loaded to 23,900 gross. Try I-70 through Colorado loaded that way, I didn't have any problems at all. Lots of high speed corners on that road, still no perceptible issue, and again I also have a dually wearing six E rated tires for comparison. This is my second dually in the last 8 or so trucks. I don't even feel that is necessary for stability until the wieghts carried on the rear axle exceed the srw tires ratings. I probably have half a million miles experience with srw trucks pulling heavy loaded gooseneck trailers. I just fail to see or feel this great difference in stability between srw and drw trucks or D and E rated tires. I think it is a shame that people beat this stability drum so loudly. The differences in my book are slim to none. The only reason I see to pony up for a dually or E rated tires is if you need the wieght capacity.



As for the CTD being so heavy, sure it is heavy, but even my Megacab only has 4400 lbs on the front axle. That is well below the tires rated capacity, I run mine at 50 psi. I also drive it like a race car over the mountain passes, with no issues from the supposedly soft and squishy D rated tires. I guess I keep in the fray here because I really truely believe, based on experience, that this obsession with D and E rated tires is crazy. When it gets right down to it, the load capacity is the number that counts.

 

[p-Bar]

It's all about the sidewalls. I will never put a load range D tire on my truck. The sidewalls are to mushy and you can't fill them to 80psi if needed. It's amazing how many tire shops will move you right into a D tire . I will pay the extra. As said before "to each his own".

 

[CBrabec]

Not to sound stupid, but I pull a trailer with lawn equipment and the total weight of everything when it's fully maxed is about 5K. I need to get new tires, so would I be safe going with a "D" range tire or should I get "E" range? Don't haul heavy loads in the bed of the truck very much, maybe once every three months.

 

[macdaddy]

Unless you have 16 inch wheels "E" rated tires may not be an option for you.



There are a couple of manf that make a 15" "E" rated tire, Denman is one.



Mac

 

[Saccowboy]

well guys coming from experience if you tow anything over 10k, i would suggest going with an E rated tire. there has been alot of mumbo jumbo on the tdr from members who need to do a little bit of research before they shoot their mouth off. ive been researching this damn tire question D's or E's for the last year and its a pain in the you know what! haha there is no myth about the letter rating system, it is what it is and every manufacturer still uses it! D=8 ply, E=10 ply, F=12 ply, G=14 ply. i fail to see what people dont understand about this?? certain people seem to think just because a tire says it will hold a max of 3195 pounds that it will do it all day and tow it just the same as if it werent loaded. thats why most E rated or better tires will hold 80psi because they will take more punishment and still hold up. now if you dont haul anything heavy this all means nothing.



first off from first hand experience i went from stock truck with 265 bfg's, 2" level kit and airbags to 315 bfg's and same truck. for the first 10k miles they seemed to be ok until i started towing on them. there is a night and day difference towing our 5th wheel. there is much more sway side to side and front to back while going through the mountains. while steering the load d tires you have to over steer all the time or the truck has a mind of its own. i couldnt imagine loading these tires up to the max and feeling safe. i am soo uneasy while towing that i will not do it again until i get new tires on there very soon. my tires are not bald, i have tried different air pressures and rotating very often but nothing seems to work.



now with about 30k and about 1/4 of the tread left i have started to get a mild case of death wobble. i have never been soo unhappy with any tire i have ever had. so i am going back to E rated tires for more sidewall stiffness, better weight carrying capacity 3750# Vs. 3195# and more peice of mind while towing.



Sorry if i was too rough on anyone, it wasnt meant to single anyone out. just needed to chime in and vent some anger on how bad the bfg D range tires have been.



Will

 

[Me808garam]

Aloha I have an 06 megacab 2500 Just put on a leveling kit and 33x12. 50 x17 Parnelli Jones Dirt Grips E rated to 3045# and an 02 with 35 s 3600# rating from 4 Wheelparts works for me. .

 

[MDarnell]

Forgot to mention the Nitto Terra Grapplers were the largest E rated tire with an on road / off road traction that I was looking for. Per Nitto's website the tire is listed at 3750 @ 80 PSI. As an earlier poster put it, more tire pressure equals stiffer side walls. For towing heavy loads, IMO, you need the stiffer sidewall to prevent swaying.



LT285/70R17 E 126R 3750@80psi

 

[BHolm]

well guys coming from experience if you tow anything over 10k, i would suggest going with an E rated tire. there has been alot of mumbo jumbo on the tdr from members who need to do a little bit of research before they shoot their mouth off. ive been researching this damn tire question D's or E's for the last year and its a pain in the you know what! haha there is no myth about the letter rating system, it is what it is and every manufacturer still uses it! D=8 ply, E=10 ply, F=12 ply, G=14 ply. i fail to see what people dont understand about this?? certain people seem to think just because a tire says it will hold a max of 3195 pounds that it will do it all day and tow it just the same as if it werent loaded. thats why most E rated or better tires will hold 80psi because they will take more punishment and still hold up. now if you dont haul anything heavy this all means nothing.



Will

Sorry Will, you need to do just a bit more research I think. I want you to show me a modern radial tire for our trucks that actually has the number of plys you listed above. I just looked at my 235/80-17 E tires on my truck. They have 1-nylon ply, 2-steel, and 2-polyester plys. That is five tread plys plus two plys of polyester on the sidewalls. That is well shy of the 10 plys you are claiming. That is an outdated system formerly used on bias ply tires which may have actually used that many, todays tires do not. That brings us back to the load rating on the sidewall.



I find it not only humurous but a little absurd to read that somehow if an E tire is rated for 3200 lbs and a D tire is rated for 3200 lbs that somehow the E version is rated for day in and out and the D isn't? Where exactly did you come up with that? It simply isn't true. No tire manufacturer in the world is going to produce a tire with a load rating that isn't for constant use. Does the D rated tire say on the sidewall "sometimes you can load it this much" :-laf Talk about bad information guys.



Then to complain that a 12. 5" wide tire was squirelly on an 8" wide rim is nuts. That tire should have been on a 10" wide rim. The instability was caused by a lack of sidewall support, not because there was something wrong with the tire itself. So you went up five sizes from stock and figured it ought to work right?



Once again, to each his own, but I have yet to see a compelling argument or a single fact proving that there is this great advantage to running E rated tires over a D rated tire with a similar load rating. Why is it soooooo hard to accept that the load number in pounds, stamped on there by the manufacturer, is the number to pay attention to. I assure you, if you are stopped by the DOT, that number is the ONLY one they care about either. They will not even bat an eye at the load range letter, it is essentially meaningless, it is a tire catagory.

 

[macdaddy]

Where's all the guy's with "D" tires mounted on 20" wheels??. I'll bet they are not to bad on the side wall flex thing.



Seems to me that is where the difference is. Thinking a "D" rated 35" mounted on a 16" or 17" with the same or close weight rating as a 17" 235/80-17 "E" will handle the same is ridiculous.



Saccowboy ain't talking smack.



Mac

 

[BHolm]

Where's all the guy's with "D" tires mounted on 20" wheels??. I'll bet they are not to bad on the side wall flex thing.



Seems to me that is where the difference is. Thinking a "D" rated 35" mounted on a 16" or 17" with the same or close weight rating as a 17" 235/80-17 "E" will handle the same is ridiculous.



Saccowboy ain't talking smack.



Mac

Oh but he is, though I am sure not intentionally. You failed to read the whole response I think. The reason the 35's didn't work for him was that HE MOUNTED THEM ON THE WRONG SIZE RIM. It STILL doesn't have a darn thing to do with D or E. There is obviously a huge difference between a 235/80-17 and a 315/70-17. The 35" tires has taller sidewalls, much taller than the stock 265/70-17 tires. OF COURSE he will feel a difference, but that difference wasn't because the tires were "only" D rated. Nobody ever said they would handle the same

 

[BHolm]

Another question would be... . what about the 305/65-17E BFG ATs that are rated at 3195lbs@65psi . Are those OK because they are E rated? What about the 65psi max pressure though? Just a little more fuel for the fire :-{}

 

[GaryCarter]

Since you asked...

Where did you get all that info .

Here's a pointer for you. Roll your eyes at this.



Link



This system's only been in use since 1991, so it's understandable you might not know about it yet.



Gary

 

[BHolm]

Here's a pointer for you. Roll your eyes at this.



Link



This system's only been in use since 1991, so it's understandable you might not know about it yet.



Gary

That info applies to passenger car tires not light truck tires. There is a drop down menu at the bottom of that page that talks very generally about the load and ply ratings though.

 

[macdaddy]

Here's a pointer for you. Roll your eyes at this.



Link



This system's only been in use since 1991, so it's understandable you might not know about it yet.



Gary

Gary



I did do a pull down on the bottom link.



They do make reference to the "alphabetical" identification and how it used to apply to the number of ply's it has. So I'll give you that Gary.



It also talks about how it is still used to identify a given tires load carrying capability. (At the bottom drop down).



However it still doesn't settle the fact that a tall LRD's side wall flex is a unstable set up when loaded to it's max weight.



Max

 

[BHolm]

However it still doesn't settle the fact that a tall LRD's side wall flex is a unstable set up when loaded to it's max weight.



Max

Back the train up a second When did it become a FACT that a LRD tire is unstable when loaded? I think that is no more than an opinion of some. That is what is being disputed, it is hardly a fact. I've seen one other response I think, that has actually done a lot of heavy running on LRD tires and not had any problem. It's not some sort of myth and continuing to ignore the real facts wont end the dispute. The numbers do not lie, the letters I am not so sure about :-laf



The original poster already bought tires in LRE. I know from my experience what works for me. Your milage may vary, as they say.

 

[macdaddy]

Back the train up a second When did it become a FACT that a LRD tire is unstable when loaded? I think that is no more than an opinion of some. That is what is being disputed, it is hardly a fact. I've seen one other response I think, that has actually done a lot of heavy running on LRD tires and not had any problem. It's not some sort of myth and continuing to ignore the real facts wont end the dispute. The numbers do not lie, the letters I am not so sure about :-laf



The original poster already bought tires in LRE. I know from my experience what works for me. Your milage may vary, as they say.

BH



I was making reference to the 33"-35"ers.



Down here in Toybox country every one and their brother are running tires such as the BFG KO's 33's and believe me it's not a myth, IT'S FACT!!!!!!.



We haul out to the offroading areas here in the So West and never a weekend goes by that you won't miss these wingnuts with lift kits and tall LRD 33-35"ers with HEAVY loads swaying from the likes of cross winds, expansion joints, (while cornering) and any other lane varying maneuvers.



Now I'm sure that experience, and seat of the pants driving skills will help with respect to under/over steer, but remember not all of these people are TDR folks.



Why not just use LRD (if you must) in a smaller diameter which affords less side wall flex.



No flame suits required!!!!



Mac

 

[BHolm]

I don't want to stray too far from the original point. I would have bought E rated tires if they were availible in the specific tire and size I wanted. I didn't go out of my way to get D rated tires.



As far as buying a smaller size than a 33", well, that would be the stock size then. Again, looking at the numbers, a 265/70-17 has only 1/2" less sidewall than a 285/70-17, making the tire just about an inch taller overall. How that makes any difference at all I do not know.



You then talk about guys with lifts and 33's or 35's. Do you think the lift could be part of the problem? Why is it automatically the D tires that get the blame?



Once again, I have personally done a bunch of heavy towing with the 285 BFG tires on three different 3rd gen CTD trucks. The problem doesn't exist. So it is he said she said :-{} And that is certainly not enough to call either side factual, though I think I have tried to put forth my side with not only extensive personal experience but the numbers that support the claims and common sense arguments. If you are going to blame the tires, I think you need facts to back that up. I personally think that as all around tires the 285 BFG is a perfect choice for these trucks, especially if winter driving is a concern. To discount it as a choice based on the letter rating is a mistake IMO.



I even ran a 285/75-16 on my CC LB 4x4 Chevy durapooch truck. That was on 6. 5" rims, still I didn't experience this wild out of control sway problem some want to tell stories about. Is there anyone reading this that has actually had a problem with a 285/70-17 BFG tire? Has it led to an accident, or even a major pucker than can be attributed to the tires?



I was trying to just bow out with the last post, and will try again with this one There really isn't much beyond some hear-say to support this notion that the D tires are inferior to the E tires if the rated capacities are similar.

 

[macdaddy]

Alright, Alright



You can have the last post!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!



Mac