Tent Trailer - Recommended Pressure > Tires' Max. Sidewall Pressure

[ls1mike]

Look at the the sidewall. The tires are not rated at 1,570.
R stands for radial construction. B means belted bias and D stands for diagonal bias construction. The last dimension listed in the size is the diameter of the wheel rim, which is most often measured in inches.

I know they are load Range C I said that. It is on the trailer placard. Load Range D is 1570.

https://www.etrailer.com/question-140866.html

The D does not mean load range D in this instance.

Here is exactly what I wrote in my first post.
"The D should be the load range. But written the way you have it is odd. I see it is that way on the placard. Are they Radial Trail HDs? I see they are rated to 81 MPH. What does it actually say on the tire? Based on the weight they look like a load range C based off the 1200 and 1360 rating."
On placard like my Passport it says C in that spot which is what the trailer came with.

I probably should have said. "Tire should have a D for load range" to eliminate confusion.

Placard vs tire, sorry for the confusion.

 

[MNgopher]

So many people confusing so many things...

The D in the tire size on the placard means the original tire on the trailer was a bias ply tire. If it were an R, it would be a radial.

65psi pressure means it was a load range D tire original from the factory.

The tires that were installed are radials (good), but Load Range C, 50 psi max. That means the tires as installed do not have the maximum weight carrying capacity as intended from the factory.

(Hint: Tires in this size come in load range B, C, and D, in both bias ply and radial. C is by far the most common, campers were a common user of the Load Range D)

 

[oil pan 4]

I'm pretty sure the D in your case means the original tires were bias ply. I wouldn't put p-metric tires on any trailer, although the Chinese trailer ties might not be that much better these days.

I run 13 inch load range E radials on my little utility trailer. None of the tire shops round here could find them. The internet found them no problem.

 

[CKN]

I know they are load Range C I said that. It is on the trailer placard. Load Range D is 1570.


Here is exactly what I wrote in my first post.
"The D should be the load range. But written the way you have it is odd. I see it is that way on the placard. Are they Radial Trail HDs? I see they are rated to 81 MPH. What does it actually say on the tire? Based on the weight they look like a load range C based off the 1200 and 1360 rating."

Yes-and the gross on the trailer is 3,000 pounds. It doesn't matter what the rating is-the weight is plainly printed on the sidewall. No matter which weight you use on the sidewall-they do not have the ability to carry the weight.

 

[oil pan 4]

Yes-and the gross on the trailer is 3,000 pounds. It doesn't matter what the rating is-the weight is plainly printed on the sidewall. No matter which weight you use on the sidewall-they do not have the ability to carry the weight.

Yeah I'd at least follow manufacturer recommendations for this one.

 

[CKN]

Tire shops are full of mental defectives do no trust them. They will kill you.

The OP is somewhat confused. There are far better sources (such as BITOG own RV Forum) where he could have gotten better answers....quite frankly. Now-there are some correct posts above-but he has to wade through some that are bad information.

And you need to buy tires SOMEWHERE-and have them mounted SOMEWHERE. I know a few on here have their own machines-but most vehicle owners do not.

 

[oil pan 4]

The OP is somewhat confused. There are far better sources (such as BITOG own RV Forum) where he could have gotten better answers....quite frankly. Now-there are some correct posts above-but he has to wade through some that are bad information.

And you need to buy tires SOMEWHERE-and have them mounted SOMEWHERE. I know a few on here have their own machines-but most vehicle owners do not.

Yeah I don't have my own tire machine. I only bring the wheels and tires to the tire shop already off the vehicle. I don't even trust them to jack the vehicle or properly torque the lugs. Almost every time I'm in a tire shop I see something that makes me cringe, and that's excluding everytime they use the impact to install lugs.
Discount tire is probably the worst.

Yeah bitog at least, RV forums at best to talk tires.

 

[ls1mike]

So many people confusing so many things...

The D in the tire size on the placard means the original tire on the trailer was a bias ply tire. If it were an R, it would be a radial.

65psi pressure means it was a load range D tire original from the factory.

The tires that were installed are radials (good), but Load Range C, 50 psi max. That means the tires as installed do not have the maximum weight carrying capacity as intended from the factory.

(Hint: Tires in this size come in load range B, C, and D, in both bias ply and radial. C is by far the most common, campers were a common user of the Load Range D)

When I get home I can take pictures of both of my placards they are both C, both are Keytsone trailers.

 

[MNgopher]

When I get home I can take pictures of both of my placards they are both C, both are Keytsone trailers.

Whats the point?

The OP's placard show the OEM tires were a bias ply, 175/80/13 tire that required 65psi, which is Load Range D.

The installed tires are Radial, max pressure 50 psi, that are Load Range C. They do not match the OEM rating for weight capacity.

The OP should advise their friend the get the correct load range (bias or radial doesn't matter, but radial is generally a better choice)

Reality is that nearly all trailers have tires at the bare minimum for load capacity, and typically assume that the required percentage of weight is carried by the tongue of the trailer. Thus how you end up with a 3000 GVWR trailer with 2700 ish lbs of tire capacity under it. (10% of the weight should be on the trailer tongue...)

 

[ls1mike]

Whats the point?

The OP's placard show the OEM tires were a bias ply, 175/80/13 tire that required 65psi, which is Load Range D.

The installed tires are Radial, max pressure 50 psi, that are Load Range C. They do not match the OEM rating for weight capacity.

The OP should advise their friend the get the correct load range (bias or radial doesn't matter, but radial is generally a better choice)

Reality is that nearly all trailers have tires at the bare minimum for load capacity, and typically assume that the required percentage of weight is carried by the tongue of the trailer. Thus how you end up with a 3000 GVWR trailer with 2700 ish lbs of tire capacity under it. (10% of the weight should be on the trailer tongue...)

Right and I said all that. I told him early on to get a set of load Range D tires, but not all placards are the same I have seen the ones you are talking about.
My first post Post 8 on this thread.

The D should be the load range. But written the way you have it is odd. I see it is that way on the placard. Are they Radial Trail HDs? I see they are rated to 81 MPH. What does it actually say on the tire? Based on the weight they look like a load range C based off the 1200 and 1360 rating.

Each tire is good to 1200lbs at 50 PSI cold. Radial Trail HDs are pretty good. It is what I have been running on my 32 foot 7800 lbs for the past 8 years. 205/75R R 14 load range D.

Single axle trailer, you need a better load range tire. Carlisle makes a load range D in that size.

 

[CKN]

Whats the point?

The OP's placard show the OEM tires were a bias ply, 175/80/13 tire that required 65psi, which is Load Range D.

The installed tires are Radial, max pressure 50 psi, that are Load Range C. They do not match the OEM rating for weight capacity.

The OP should advise their friend the get the correct load range (bias or radial doesn't matter, but radial is generally a better choice)

Reality is that nearly all trailers have tires at the bare minimum for load capacity, and typically assume that the required percentage of weight is carried by the tongue of the trailer. Thus how you end up with a 3000 GVWR trailer with 2700 ish lbs of tire capacity under it. (10% of the weight should be on the trailer tongue...)

I don't disagree-but the issue is that 95% of tent trailer owners don't use a weight distributing hitch-that would help.

 

[MNgopher]

Sigh - arguing that weight distribution hitches should be used on a 3000lb camper and what the "D" means in a tire size.

OP - have your friend find the right tire for the trailer - it needs to have a 65 psi rating and will likely be a special order. Most tire shops do not stock anything besides the most common Load Range C, 50 psi tire. Many tire shops won't even be able to figure that out, and your friend should likely order them online to get what is required.

 

[ls1mike]

Sigh - arguing that weight distribution hitches should be used on a 3000lb camper and what the "D" means in a tire size.

OP - have your friend find the right tire for the trailer - it needs to have a 65 psi rating and will likely be a special order. Most tire shops do not stock anything besides the most common Load Range C, 50 psi tire. Many tire shops won't even be able to figure that out, and your friend should likely order them online to get what is required.

Fair enough. I can tell you this I am lucky to live here in Washington most of the places around here carry a ton of trailer tires. I have never had to wait for a tire load range D or better tire. The Subvets float has a 16 inch load range E Radial trail HD. The float itself is light. The Trailer is a 1966 equipment trailer. The tongue weight is stupid. Thing was used for bulldozers and heavy equipment for years. It is overkill for what we do with it but we got a decent deal on it.

 

[Number_35]

Respectfully-you are trying to help and apparently don't know what you are doing.....now that I read the above posts.

Do you even tow?
THOSE TIRES ARE TRAILER TIRES,BUT THEY APPEAR TO BE NOT TO HAVE THE PROPER WEIGHT CARRYING ABILITY THAT IS NEEDED.

You're quite right - I don't tow (or not personally; I used to for work), and have not seen the tires in question, which is why I'm seeking the knowledge, experience, and wisdom of the BITOG members. No offence taken.

@ls1mike's post (#13) has a linked list of Radial Trail HD tire specs. The ST175/80R13 has a C load rating, a rated load of 1360#, and a maximum pressure of 50 PSI. That's the same as the new tires.

Thanks for putting me onto the D in the tire spec meaning diagonal (a construction spec, rather than the load rating). Regardless, these tires being rated for pressure and payload like the C load-rated tires in the linked specs, look like they're also C load-rated.

In the same table, the D load-rated tires in ST175/80R13 have a load rating of 1570# and a maximum inflation pressure of 65 PSI, both of which meet the trailer's requirements.

I suspect the new tires are C load-rated, and the shop should have installed D.

 

[Number_35]

The owner has bought the proper tires (D load-rated) from another shop - a dedicated tire store, rather than a seller-of-many-things.

The first store has so far refused to take the unused tires back because they were purchased > 30 days ago.

The owner took the original worn tires (65 PSI, 1570#) in on the trailer wheels, and asked the first store to replace them with the equivalent. They claimed they had. Definitely the fault of the people there.

Thanks, all, for your input. I learned a lot.

 

[CKN]

The owner has bought the proper tires (D load-rated) from another shop - a dedicated tire store, rather than a seller-of-many-things.

The first store has so far refused to take the unused tires back because they were purchased > 30 days ago.

The owner took the original worn tires (65 PSI, 1570#) in on the trailer wheels, and asked the first store to replace them with the equivalent. They claimed they had. Definitely the fault of the people there.

Thanks, all, for your input. I learned a lot.

I'm not one to write letters often-and with me it would be the principle of the issue rather than the money. They place you bought them from potentially put your friend in an "unsafe condition". I would use those words in a letter to the owner (and copy the Manager) of the business in question. It's easier for them (and "soft dollars") to give your friend a credit/gift card for the tires-if there are other things they sell which can be purchased at later dates. If not-demand a check refund.

 

[Rmay635703]

The sad part is anything 13” is rare in any size other than 155r13

Manufacturers that spec 12 or 13” tires are ignorant of the us tire market.

Further I would agree with getting a tire with better than the D rating just because tires run over 60% of their weight rating wear rapidly so any additional margin reduces frustration a lot.

 

[Number_35]

I'm not one to write letters often-and with me it would be the principle of the issue rather than the money. They place you bought them from potentially put your friend in an "unsafe condition". I would use those words in a letter to the owner (and copy the Manager) of the business in question. It's easier for them (and "soft dollars") to give your friend a credit/gift card for the tires-if there are other things they sell which can be purchased at later dates. If not-demand a check refund.

Pretty much my thoughts word-for-word. The manager was not in today, but, as a first step, my friend is planning on going back tomorrow to meet with him.

 

[Elkins45]

The only way I would ever buy a trailer tire with a load range < D would be if I had to replace a blown tire in order to get home. That’s especially true for 13” tires because most of them are garbage now.

 

[Number_35]

The only way I would ever buy a trailer tire with a load range < D would be if I had to replace a blown tire in order to get home. That’s especially true for 13” tires because most of them are garbage now.

I have learned much today!