RV Tire Safety: Goodyear Endurance tire load capacity explained

Here’s a question I received from an RV Travel reader recently about Goodyear Endurance tire load capacity:

Hope you can clear up a bit of confusion regarding the Goodyear Endurance.

For background, I’m on my fifth set of tires on my fifth wheel, which I’ve now towed 65,000 miles in ten years. One set OE tires, two sets of Maxxis, then Goodyear Endurance ST235/80R16, and now Endurance ST235/85R16. I use a TPMS and do a walkaround at each stop. Never had a blowout but a few bubbles and tread separations requiring replacements.

Have weighed the trailer at each wheel a couple times and run pressures based on the load inflation tables—which ends up being the max of 80 psi for the ST235/80s. Unfortunately, this only gives me a couple percent of safety margin as it’s a big, heavy trailer.

I checked clearances and rims—stamped for 110 psi on inside—and went with the ST235/85 Endurance to be able to run higher pressures and get 15% or so for a factor of safety.

Which brings me to the confusion. The Endurance ST235/85 tire is labeled as a Load Range E with Max Inflation of 80 psi. The Goodyear Load Inflation Table for the ST235/85 goes beyond 80 psi, showing loads at 95 and 110 psi, which I guess would be Load Ranges F and G. I choose to run them at 95 psi to get the factor of safety I want.

I called Goodyear to figure out why the tire markings don’t match the Load Inflation Tables for max load and pressure and see which to use. The customer service folks were initially confused but checked with their engineers and then got back with me and said to ignore the tire markings but use the load inflation tables. Which is what I’ve been doing.

So, two questions:
1. Am I OK with my logic and running the loads and pressures over the tire markings but within the guidance of the Load Inflation Tables?

2. If you know anyone at Goodyear, can you ask them why they don’t change the markings on the 235/85 tires to match the Load Inflation Tables?

Sorry to be so wordy. I enjoy your blog, thoughts and analysis and appreciate your commitment to getting the word out on common sense tire safety. Thanks.

My response

Yes, the information you were given is confusing. I believe the cause of this confusion is the fact that the customer service person you talked with does not have much experience with tires in RV application. I decided to visit a Goodyear dealership in Akron that specializes in HD tires, such as ST type. He was able to confirm that the Load/Inflation Table, published in 2016, was a bit out of date and did not reflect the current line of Endurance tires.

While it is correct that a Goodyear tire in Load Range “G” with a size 235/85R16 can support a load of 3750 lbs. at 110 psi, it isn’t a Goodyear Endurance but rather a Goodyear Unisteel G614 RST. LT235/85R16 LR-G. You can find this tire on page 17 of this Tire Guide.

Comment for people with large and heavy trailers

There are tires that can carry extra heavy loads. These would generally be found under a listing for “Commercial” all steel tires, and many tire companies make this type of tire. As all steel Commercial tires, you will find that they are more expensive than “lighter weight” tires with polyester body cord. If you are going to consider using this type of tire, it is important that you confirm the psi rating for the wheel. I would consider bolt-in metal valve stems a must.

Roger Marble

Check out my Blog www.RVTireSafety.Net

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