ST-D rated tires vs ST-E rated tires

[Eagle & Bear]

I have been running ST 225/75/15 D on my 1976 29' AS for the past 10 years. I need two new tires but they are telling me that no one is making ST D rated tires any more and they only have ST E rated tires.

When we first started traveling I read a post by Andy R. He said that the D rated tires are good but the sidewalls of the E rated tires are too stiff and will lead to frame cracks and shell fatigue.

Any opinion on D vs E rated tires?

Can I run two Ds and two Es at the same time?

Thanks,

Michael

[CapriRacer]

Yes, you can run both LR D and LR E tires at the same time (on a trailer), but at the same pressure and not as a dualled pair (one of each).

And just to be clear, a dualled pair would have 4 tires on an axle, and a tandem pair (the usual configuration for a trailer), would have 2 axles with 2 tires on each axle for a total of 4 tires.

[Bill M.]

Goodyear shows a D rated 15" tire in the new Endurance line. I think it is a 205 instead of a 225 but it has plenty of load range. I think it is actually about the same size my trailer came with. Check the Goodyear website. Do not know how available it is. I have concerns similar to yours. I also used to read Andy. I am not about to put E tires on my trailer. Do people think the E tires are "stronger" just because they can carry more air?

If you run the E tires at 50 psi will they heat up and blow out? Will the trailer sway? Is interplay shear worse?

[Morgan guy]

I have been running E rated tires on my trailer for several years, about 7,000 miles. They are rated at a max pressure of 80 pounds. I run them at 75 or a little less. I have had no problems with them heating and no problems with the trailer either.

[Eagle & Bear]

Thanks everyone for the responses. Not sure what two Ds on the front axle and two Es on the second axle will or will not do to our AS. This is the second time that Discount Tire has gotten the tire load range wrong. If I want to have them replace the two Es they would put on a pair of Carlisles. Last time I used Carlisle the tire tread became cupped after 500miles. I think I will go with the Ds on the front and Es on the rear. Since this is fairly well documented, if I break a frame I will call Discount and see if they will pay for frane failure.

[CapriRacer]

I am apologizing ahead of time for those who recognize this post is redundant, but in case it is not:

Originally Posted by Eagle & Bear

Thanks everyone for the responses. Not sure what two Ds on the front axle and two Es on the second axle will or will not do to our AS. This is the second time that Discount Tire has gotten the tire load range wrong. If I want to have them replace the two Es they would put on a pair of Carlisles. Last time I used Carlisle the tire tread became cupped after 500miles. I think I will go with the Ds on the front and Es on the rear. Since this is fairly well documented, if I break a frame I will call Discount and see if they will pay for frane failure.

Sorry, but the opposite is true. You can replace LR D tires with LR E tires and use them at the same pressure - and they will be functionally equivalent. There is no difference in load carrying capacity and it is the inflation pressure that matters most with regards to a tire's spring rate - hence there is no additional problems caused by using a higher load range. (which is why Goodyear now offers LR E's, where they used to have LR D - and Discount Tire knows that.)

[Ruscal]

I set our 80 psi Michelins at 74 on our last trip. The Michelin "weight/pressure chart verified the tire could carry the weight of our trailer at 74psi. Our trip was mostly freeway driving in warm weather. The tire monitor reported a max temp of 95F. 95F is cool enough to not cause sidewall separation. Michelin recommends setting temp warning alarm at 150F or so. Visually the tires had a little bulge which would let the tire ride a little smoother than when set at 80psi. When we arrived at our destination nothing was tossed around or on the floor, so I think we have a workable pressure for our trailer.
Russ