Tire Load Rating - Size Question

[MDarnell]

Few questions/concerns regarding upgrading to new tires.



Have: 2004, 2500, 4. 10, LWB, Quad Cab, 4x4, 6spd Manual. Currently still running Michelin LTX-A/S LT265/70R17 tires with Load Range E. Per Michelin's website, this tire is rated at 3195lbs at 80psi. Everything else on truck is stock. Moderate towing with gooseneck equipment trailer, and off road hunting, but mostly commuting highway miles. Live in Southern PA, so snow isnt too bad in the winter.



Want a nice A/T on/off road tire but in a LT285 or larger range.



I have found the following:



Goodyear Wrangler MT/R in LT305/70R17 D. This tire has rating of 3000lbs @ 50psi.

Goodyear Wrangler MT/R in LT285/70R17 D. This tire has rating of 3195lbs @ 65psi.

BFG AT T/A KO in LT285/70R17 D. This tire has rating of 3195lbs @ 65psi.



My question is what issues might arise from going down from Load Range E to load Range D even though the weight ratings are equal but at different PSI's?



Is there a better tire that I should be looking at? Would like to upgrade to larger tire, but not really lift the truck to do so.



Thanks.

 

[JCasper]

Load rating is for someone else to answer, all I know is you will probably get more sidewall flex with a D rated tire. I am going through the same process right now. I am wanting to put on 35's but I don't want to feel unsafe towing. You can buy a 295/70/17 Toyo M/T in a E rated tire. Also there is a 285/70/17 Tire in the Toyo A/T. I am currently considering both of those for a E Rated tire.



Good luck, and let us know what you decide on.



Joe

 

[Prairie Dog]

Stick with load range E for towing. The stiffer side wall makes for a much more controlled ride. I learned this the hard way with my first gen when I put on load range D's that had a higher weight load rating than the stock E's. The softer side walls made driving with a trailer very fatiguing because the truck moved arround so much.



Scotty

 

[DPelletier]

Yep,

If you're towing or hauling heavy, stick with the "E"s. Less sidewall flex and sway



Cheers,

Dave

 

[Graphic man]

I agree, stay with an "E" if you can!!

 

[KD7GYJ]

Yea, I'd stay with load range "E" tires also.



I took my truck into Sam's Club and told them the tire size I was looking for. They guy say's "Got the right tire right here!" and picks up two tires and wheels them out to have them put on the front rims.



Come to find out, he mounted "C" rated tires and man, I wanted them removed and replaced with "E" tires for safety. I was towing a small enclosed trailer and my front end was all over the road. It thought it was weird that my steering was so goofy.



They ordered the correct tire and swapped them out. They are still sitting on the tires because they aren't defective and they have about 3K miles on them.



You're better off going with a smaller tire and sticking with the "E" rating.



Best of luck.

 

[Jeepr]

I had the same dilemma. I went with Procomp Extreme All-Terrains in 305 65R17. This is supposedly equivalent to a 33", but they are only negligably larger than the stock Rugged Trails. They are wider though, and one of the few E load range available. They have a 35" size also. You might want to take a look.

 

[BHolm]

I guess I will be the dissenting vote. I have run D and E tires on mine. I now stick with BFG AT KO's in 285/70-17. I ran them for a full 40K on the work truck that pulled a heavy 32' gooseneck trailer. I also had them on my '05 and now on my '06. A couple months ago I drove a 3000 mile round trip with the trailer behind. I scaled at 14,900 with the trailer empty and 23,900 loaded. I pulled all the way across Nebraska and over several mountain passses in Colorado on I-70. I never once felt the sidewalls were too soft and I have a dually to compare to. The BFG AT has a triple ply sidewall, I doubt you will be able to tell any difference. They look better, are great off road and in the snow.

 

[juicedcummins]

I run the ko's also and run heavy, hard. They ride better than the E's and are rated for more than your truck.

 

[MDarnell]

Thanks for all the good feedback. I like to hear of your situations so I can compare to mine. Does going with a D rated tire affect the warranties at all? I can get the AT KO's put on tomorrow if I wanted but still struggling with this decision.

 

[BHolm]

The truck warranty? No way. Like juiced said, the 285 D range tires will carry more than the truck is rated for. You have nothing to lose. They look better ride better and handle loads easily. I make it a habit to check the tires at every fuel stop when I am hauling like that. I never noticed excessive heat build up or anything. Tread wear is nice and even too. I've never understood why some get so hung up on the letter on the tire. It used to relate to the number of plys in a tire. It doesn't anymore. The real concern should lie with the actual amount of weight the tire is rated to carry. Since the bigger tire can carry the weight, I don't understand where the concern is



I actually think the wide rims Dodge puts on the trucks makes a big difference. I had a Chev D/A that I hauled with too. Those trucks come with 6. 5" wide rims compared to our 8 inchers. I ran that truck on stock 245 E tires for a while, then went up to 265 E tires. It did OK but when I put the 285's on the 6. 5 rim I could then feel a difference. I don't feel any difference with the 285s on an 8" rim. Going up to 315s on the 8's might be enough to make it a little squirrley again.

 

[DPelletier]

The load carrying ability is one issue. Sidewall deformation and flex is another. I also run the BFG All Terrain KO's on my Jeep Wrangler and I love them, but I wouldn't put them on my truck. It depends what you're towing/hauling. I have my truck up over it's 12,000 lbs GVWR and would never run any load range D tire on it. When you are hauling a heavy slide-in, you WILL notice the difference in air pressure regardless of the tire's construction.



my 2 cents,

Dave

 

[Task125]

I am torn also. I might go with the toyo 295 17. could not find it on there web site.

anyone have pics with this size tire on there truck?

 

[RTillery]

I've run the 295 Nittos here in Colorado and been pretty happy with them but I seldom tow. They are a D rated tire, but I see Nitto has come out with an E rated 285. Anyone on here tried the E's yet? Might be worth a look as my D's are a huge improvement in traction over the Mich's.

 

[GaryCarter]

My understanding is the "D", "E" etc. is obsolete terminology (but still hanging on in usage). "Ply ratings" were divorced from actual ply counts a long time ago.

Current ratings are by the numerical + letter system e. g. 121R, where 121 is the load rating and R the speed rating.



A good clue to how stiff a tire will be is whether it's rated at 80, 65, 50, 35 psi etc. More pressure = stiffer ride.



Gary

 

[cwbyinjeep]

I ran BFG AT 295/70's E on my PSD Ford Excursion and loved them. They handled great, did great in the wet and lasted 50+k with proper maintenance.

 

[MDarnell]

Decided on the LT285/70/R17 E rated Nitto Terra Grapplers. Got them put on today. Looks good, feels good, will keep all posted on their performance.



Thanks again for all the feedback.

 

[BHolm]

The load carrying ability is one issue. Sidewall deformation and flex is another. I also run the BFG All Terrain KO's on my Jeep Wrangler and I love them, but I wouldn't put them on my truck. It depends what you're towing/hauling. I have my truck up over it's 12,000 lbs GVWR and would never run any load range D tire on it. When you are hauling a heavy slide-in, you WILL notice the difference in air pressure regardless of the tire's construction.



my 2 cents,

Dave

Thats just bad information though Load carrying and sidewall deformation are almost directly related. The heat generated by a tire occurs as it deforms upon every revolution of the tire. The bigger the load, the more deformation and from there the manufacturer can assign a load rating not only with a letter but with an actual load carrying capacity NUMBER.





You clearly have a DRW truck, and the only tires that fit it are E range tires. The only trucks that should be carrying large heavy slide in campers are the DRW trucks. That isn't at all what was being considered. It was a SRW truck, and the only number that really matters is the load carrying capacity number The tires construction also does matter. I have E rated tires on my 34' motorhome. I normally run michelins because they are contructed in a heavier fashion. I have them on the front, needed rears on short notice and put Firestones on of the exact same specs. The Michelin sidewalls were twice as thick and much stiffer than the Firestones. Construction, even among tires of the exact same specs, makes a difference. BFG AT's have heavy thick sidewalls, and that makes a difference

 

[DPelletier]

Thats just bad information though Load carrying and sidewall deformation are almost directly related. The heat generated by a tire occurs as it deforms upon every revolution of the tire. The bigger the load, the more deformation and from there the manufacturer can assign a load rating not only with a letter but with an actual load carrying capacity NUMBER.





You clearly have a DRW truck, and the only tires that fit it are E range tires. The only trucks that should be carrying large heavy slide in campers are the DRW trucks. That isn't at all what was being considered. It was a SRW truck, and the only number that really matters is the load carrying capacity number The tires construction also does matter. I have E rated tires on my 34' motorhome. I normally run michelins because they are contructed in a heavier fashion. I have them on the front, needed rears on short notice and put Firestones on of the exact same specs. The Michelin sidewalls were twice as thick and much stiffer than the Firestones. Construction, even among tires of the exact same specs, makes a difference. BFG AT's have heavy thick sidewalls, and that makes a difference

I don't think so, lots of load range D tires in the larger sizes have load ranges equal to or higher than smaller, stock sized E tires and due to the difference in tire pressure, the D's do have more deflection (all things being equal) FWIW I have 8 trucks currently and my '03 is the only DRW among them. I will give you that the tire construction does play a part and that not all D's (or E's) are created equally, BUT when you are loading your truck up to it's max GVWR on a regular basis (be it a SRW OR a DRW), the E's are much more stable and resistant to sway with thier 80-85PSI. Slide-in campers (even the ones that are capable of being carried by a SRW truck) are inherently top heavy and can induce heavy sway unless the truck is set up properly for it.



A friend of mine owns a fire protection company and has a small fleet of Ford PSD's ( Yeah, I know!). Anyway as soon as he buys them he rushes off to the tire store to swap out the stock E's for some big azz D range tires. When I picked up my last Dodge, he stopped over and asked me when I was going to put some big tires on it. I told him never and proceeded to demonstrate the stability of the truck by pushing sideways on the box. Did the same to his truck and the difference was very noticable. Two weeks later, one of his crew crashed an F350 towing a load of sprinkler pipe on the highway 'cause the trailer started to sway. Now, I realize that there are potentially other issues that may have contributed to the wreck, but Bill doesn't bug me about my stock size load range E tires anymore. :-laf



As far as I'm concerned, with the weight of the big Cummins on the front, these trucks should always be considered loaded and although a set of decently constructed D's are OK on an empty or lightly loaded CTD, mine will forever wear E's.



Cheers,

Dave

 

[macdaddy]

My understanding is the "D", "E" etc. is obsolete terminology (but still hanging on in usage). "Ply ratings" were divorced from actual ply counts a long time ago.

Current ratings are by the numerical + letter system e. g. 121R, where 121 is the load rating and R the speed rating.



A good clue to how stiff a tire will be is whether it's rated at 80, 65, 50, 35 psi etc. More pressure = stiffer ride.



Gary

WOW!!!!!!!!!!!!!!



Where did you get all that info .



I am sure that all the lettering stuff means absolutely nothing, and is there only to raise one's eyebrows HMMMMMMMMMMMMMMM!!!!!.



I guess all that lettering nonsense should be ignored on the 19. 5's as well,with respect to the 12 and 14 ply tires "F", "G",Ratings.



I am still waiting to here from you gentlemen with the killer "Death Wobble", and how it seems to be related to tall "D" rated tires.



Mac