D vs. E rated tires on F350 with Supertramp truck camper? Are D's OK to use?

[SimplyAnAdventure]

First off please read this entire question before just saying "NO".

I have a 2023 F350 Tremor with a 7.3L Gas Engine. This truck was ordered specifically for a Supertramp Camper that should weigh between 1200-1300lbs dry. Truck is new with 300 miles on it and I'm thinking about taking off the factory tires and selling them while they are still worth a decent amount. All the literature I read about the 2023 Tremors is they fit 37's with ZERO modifications.

Question, is it reasonable to buy a set of Nitto Ridge Gaplers in 37x11.50 R18 that are D rated, or should I buy the 37x12.50 R18 that are E rated? I would definitely prefer the more narrow tire (on my Tacoma I ran 255x85 R16's and LOVED them).

Specs from Nittos website shockingly show very very little difference in weight ratings.

37x11.50 R18's have a Maximum load rating of 3860lbs at 65 PSIG and weigh 76.63lbs
37x12.50 R18's have a Maximum load rating of 3970lbs at 65 PSIG and weigh 83.39lbs

My front axle GAWR is 4800lbs and my rear GAWR is 7050lbs so both tires techically more than cover that. Both tires are approved for the stock 8" wide rim my trucks GVWR is 11,500lbs and my payload capacity is 4214lbs.

The advantages I see on the D rated tire are a likely better ride, a decent amount less rotational mass and the narrow profile I would prefer that also falls more in the middle of the recommended rim sizes, also less likely to throw mud down the side of the truck.

The advantages I see on the E rated tire are likely more puncture resistance on the sidewalls and possibly better ability to hold a bead at lowered pressures (though maybe I have this wrong)

Price isn't a concern as I can't imagine they are much difference.

Which tire is better for my usage? Truck even with the camper will likely never weigh more than 10K but I am still nervous about D rated Tires on a one ton truck. Please help me one way or the other.

 

[ExpoMike]

Given the D rated tire is only losing 110lbs of capacity per tire, that's not a huge difference as they are still over the GVRW rating of the vehicle. The narrower tire and less rolling weight of the 11.50 will likely help slightly in fuel mileage. Given the weight of the full rig, you might find the D rated a little mushy feeling compared to the E rated one which should have a stiffer sidewall.

Hummm.... that's a tough decision. In my head I am saying E rated but the logical size thinks the D rated one could be better. Good luck with the decision. I am dealing with tire decisions for my Xterra and keep going back and forth so I understand this feeling.

 

[Todd n Natalie]

Given the D rated tire is only losing 110lbs of capacity per tire, that's not a huge difference as they are still over the GVRW rating of the vehicle. The narrower tire and less rolling weight of the 11.50 will likely help slightly in fuel mileage. Given the weight of the full rig, you might find the D rated a little mushy feeling compared to the E rated one which should have a stiffer sidewall.

Hummm.... that's a tough decision. In my head I am saying E rated but the logical size thinks the D rated one could be better. Good luck with the decision. I am dealing with tire decisions for my Xterra and keep going back and forth so I understand this feeling.

Agree with above. Really too bad the E rated tire doesn't come in a 11.5.

I'm running E rated 35x11.5 AT3's on my F150 and you're right, it doesn't throw as much crap down the side of the truck.
I also didn't have to do any trimming.

 

[SimplyAnAdventure]

Given the D rated tire is only losing 110lbs of capacity per tire, that's not a huge difference as they are still over the GVRW rating of the vehicle. The narrower tire and less rolling weight of the 11.50 will likely help slightly in fuel mileage. Given the weight of the full rig, you might find the D rated a little mushy feeling compared to the E rated one which should have a stiffer sidewall.

Hummm.... that's a tough decision. In my head I am saying E rated but the logical size thinks the D rated one could be better. Good luck with the decision. I am dealing with tire decisions for my Xterra and keep going back and forth so I understand this feeling.

That's EXACTLY what's bouncing through my head, on paper, they seem 100% fine, but something about a D rated tire on a 1T truck, just doesn't seem right...

 

[csj]

Here is my experience with my 2015 Ram 2500 diesel, I bought the truck new and immediately put a Carli pintop kit on and D rated Toyo mt 37x13.5x 18 tires.
I have not had any issues with running D rated tires, I mostly run unloaded but 25% is towing a 9500lb trailer. The one thing to note is I only get 25,000 miles at best out of them and I've gone through two sets of these. This last set I went with E rated 37" Yokohama's and they seem to be doing much better for wear, currently at 20k and looking like I'll get 10-15 more. I don't know if the rubber compound is different from D to E rating but it looks like it to me.

 

[Tex68w]

D will be fine but you'll find the E's better if you tow north of 10K. I wouldn't hesitate to run the D's if those are the width you prefer.

 

[tacollie]

I would run the D rated tires.

 

[deserteagle56]

If you spend a lot of time driving gravel or rocky dirt roads you need an "E" rated tire. Not just "E" rated but with the maximum number of plies in the tread area. My experience has been that the "E" rated Toyo Open Country M/T tires, and the Maxxis Razr tires (there may be others, I don't know) that have seven full plies in the tread hold up best against rock punctured tires. This is what all the mine trucks around here run, and what I have on my 4x4 van. A lot of both "D" and "E" rated tires have only 5 ply tread and don't hold up as well.

 

[Copperhead14]

I am in the same situation with a 2500 Ram cummins.

I would love a 37x11.5 in 17 or 18 load range E.

 

[sam-aye-am]

I recommend either going with the E or waiting until you can get actual axle weights fully loaded for the longest trip you expect to take. I know only 220 lbs difference per axle, but you’ll be surprised at how quickly it adds up. It might even make you consider an entirely different brand and/or size. If you ever intend to tow with camper loaded or do a hitch mounted moto carrier….there is even more weight pretty much all on the rear axle.

I also recommend focusing on load index instead of letter rating. Much more precise. I know for Toyo on the size I run, there are a couple options with different load index but same load letter category.

I had a 2007 Ram 3500 SRW, 4x4, Crew cab, short bed with the 6.7 CTD. I put a 2008 Outfitter Apex 8 on it (probably heavier than the super tramp) and weighed in at over 10.6K lbs total fir a 3 week trip with 2 adults. I can’t recall what empty weight was for the camper, but was several hundred pounds more than the “brochure “ weight. I now have a different camper and truck, but same thing: camper weighs significantly more than advertised weight.


Sent from my iPhone using Tapatalk

 

[SimplyAnAdventure]

@SimplyAnAdventure I say Ds because sounds like you'd prefer to run a narrow tire.


Out of curiosity, what does the truck Tire Placard say for front and rear pressure ?

And what is the max pressure and load marked on the the current oem tires ?

60 in front, 75 in the rear max pressure on the duratracs is 80.

 

[SimplyAnAdventure]

Great info from everyone. Thank you all so much for taking the time.

I think what I’ve decided is to wait and run these stock 35’s until they’re smoked. My main reason for this is I absolutely 100% need a full size spare. And it seems that to get a 37” tire up under the tremor you need Carli’s amazing, albeit very expensive hitch. $3300 for a hitch plus 5 37” tires looks like close to $6k for an extra inch of clearance. I definitely see it in the future but perhaps now isn’t the time. Maybe there will be E-rated/ 10 ply equivalent 37x11.5’s by then!

 

[PirateMcGee]

Have you tried to go anywhere but weren't able to make it because your truck was 1" too low? Will 37s make you get out more than you do now?

Rarely is this the case and bigger tires cause all sorts of issues and cost a ton. Vast majority of offroad in this country is public land navigated by stock base model 4wd trucks with open diffs.

 

[SimplyAnAdventure]

Have you tried to go anywhere but weren't able to make it because your truck was 1" too low? Will 37s make you get out more than you do now?

Rarely is this the case and bigger tires cause all sorts of issues and cost a ton. Vast majority of offroad in this country is public land navigated by stock base model 4wd trucks with open diffs.

Na, I had a Tacoma with 255x85R16’s (33’s) that was pretty unstoppable. Obviously 1” of clearance makes little to no difference especially with a rear locker and LSD up front. The 37’s were more to
Fill out the whee wells, my thought was if I was going to do it, do it now, while my other tires had barely a few hundred miles in them and sell them to offset the cost. I don’t think running 37’s on a Tremor with 4.30 gears would cause too many issues. Ford specifically made some modifications to the 23 model year so 37’s would run stock. But still I will put this project off in favor of some more important upgrades.

 

[BikePilot]

I think either will be fine. I run 37x12.50 E rated tires (Falken RT-01S) on my Ram 3500. I love them. They don't look or feel wide on a truck of this size.