TT tire wheel upgrade?

[Airdale]

Going from the OEM ST205/75R14 to the ST215/75R14 is "plus sizing" from the OEM designated size. There are proper industry standards to follow when plus sizing. I recommend following them.

[Bob K4TAX]

Originally Posted by BMullins46

I notice you mentioned that you are planning to buy 3 tires, I assume you plan on using the existing spare for the 4th on the ground tire? DON'T DO IT! leave that spare where it is and put 4 new tires on the ground. ( since I am unfamilar with your model I am assuming it has 2 axles). If I am wrong then 3 tires is fine. Be sure to have the mounting tire shop install the screw in all steel valve stems, they will save you a lot of headaches.

Replace all of them including the spare. Chances are that it has dry rot. All tires should be the same brand and size. We put 5 new Carlisle 215/75/14's on our trailer. Same size as the originals, except we went from a C to D rating tire. The originals were 5 years old and had zero treadwear.

[mnoland30]

Airdale, please tell us more about the industry standard. Silly me, I always thought it was to size the tire to barely hold the weight of an empty trailer, so it would be automatically overloaded when actually traveling with it.

I know once I went to a higher speed rating, higher load rating, and slightly wider tire, I quit having blowouts. I kind of like the idea of having a load capacity (on a dual axle trailer) that could support the trailer in case one tire goes flat, without damaging the tire that didn't blow.

[Mike134]

Originally Posted by Airdale

Going from the OEM ST205/75R14 to the ST215/75R14 is "plus sizing" from the OEM designated size. There are proper industry standards to follow when plus sizing. I recommend following them.

Yes like be sure it fits on the rim, fits in the wheel well, and has a load rating at least as much as the OEM.

If I've missed something, please quote the chapter and verse of the "standard"

[Boomerweps]

Hassle with Amazon, got confused and ordered the wrong diameter tire (I know!). Tried to cancel the order within 15 minutes of ordering. They denied my cancellation due to them already being prepped for shipment. Incredible!
Anyways, sent them back, awaiting the return on my CC. Had ordered three for the spare.
Ordered just two from WalMart. Said I’d get them 29th, got them this AM. Hope to get them installed this weekend. SIL picked up a tire removal/installer machine to use for all the demo derby cars he works on. No balancing machine. Going to check on balancing them at a local tire shop.

[Airdale]

Originally Posted by Mike134

Yes like be sure it fits on the rim, fits in the wheel well, and has a load rating at least as much as the OEM.

If I've missed something, please quote the chapter and verse of the "standard"

You forgot to check with the vehicle manufacturer. USTMA page#37/42.

https://www.ustires.org/sites/defaul...uckTires_0.pdf

[NavyLCDR]

Originally Posted by Airdale

You forgot to check with the vehicle manufacturer. USTMA page#37/42.

https://www.ustires.org/sites/defaul...uckTires_0.pdf

USTMA guidelines are not legal requirements, only recommendations.

[Airdale]

Originally Posted by mnoland30

Airdale, please tell us more about the industry standard. Silly me, I always thought it was to size the tire to barely hold the weight of an empty trailer, so it would be automatically overloaded when actually traveling with it.

I know once I went to a higher speed rating, higher load rating, and slightly wider tire, I quit having blowouts. I kind of like the idea of having a load capacity (on a dual axle trailer) that could support the trailer in case one tire goes flat, without damaging the tire that didn't blow.

When you use a replacement tire with the same size designation and just add a higher load range you just have to insure the wheels/valve stems are capable of supporting the inflation pressure you're going to use with the replacements.

When using a replacement tire with a size designation different from the tires on the vehicle certification label that label becomes invalid. For proper use of the different designated size the procedure for doing so can be found in many tire industry manuals including the USTMA Standards manual.

[Mike134]

Originally Posted by Airdale

You forgot to check with the vehicle manufacturer. USTMA page#37/42.

https://www.ustires.org/sites/defaul...uckTires_0.pdf

You do understand the difference between a "guideline publication" and a bonified "standards" don't you?

[Airdale]

Originally Posted by NavyLCDR

USTMA guidelines are not legal requirements, only recommendations.

The U.S. Tire Manufacturers Association (USTMA, formerly known as Rubber Manufacturers Association) and Tire Industry Association (TIA) standards.

This is a short excerpt from a NHTSA publication: To maintain tire safety, purchase new tires that are the same size as the vehicle's original tires or another size recommended by the vehicle manufacturer.

You should be able to find that verbatim in your vehicle's owner's manual

[NavyLCDR]

Again, only recommendations. Different size tires can meet all safety standards, they are not required to be approved by the vehicle manufacturer. But we've gone back and forth about this many times before, you have your opinion and about 90% of people who are interested in making a tire size change are going to disagree with you and not concern themselves with whether or not the vehicle manufacturer approves the new size or not.

Especially when moving from 205 to 215/70R14 the difference in which is 0.6" in diameter, 0.4" in width, and minimum rim width requirement of 5.5' instead of 5".

Now if there was an actual legal requirement to get vehicle manufacturer's approval first, that would be different, but you have never provided such a legal requirement in any of your past posts.

[Airdale]

Originally Posted by NavyLCDR

Again, only recommendations. Different size tires can meet all safety standards, they are not required to be approved by the vehicle manufacturer. But we've gone back and forth about this many times before, you have your opinion and about 90% of people who are interested in making a tire size change are going to disagree with you and not concern themselves with whether or not the vehicle manufacturer approves the new size or not.

Especially when moving from 205 to 215/70R14 the difference in which is 0.6" in diameter, 0.4" in width, and minimum rim width requirement of 5.5' instead of 5".

Now if there was an actual legal requirement to get vehicle manufacturer's approval first, that would be different, but you have never provided such a legal requirement in any of your past posts.

"In a lawsuit, the industry standard is usually used to establish negligence or failure to perform under a contract. If one performs at a level lower than the industry standard, the plaintiff may say that the defendant failed to meet the applicable standard, and should therefore be found liable."

In part; NHTSA set an industry standard for replacement tires when they mandated that the first stop when seeking replacement tires is the vehicle manufacturer's recommendation.

Anyone can ask NHTSA for an interpretation.

https://isearch.nhtsa.gov/#:~:text=N...%20promulgates.

Here is a statement from a CFR 570.62 document: Tires with a major deviation from the size recommended by the vehicle or tire manufacturer, is a cause for rejection.

I see that as a tire industry precedent.

It takes too much time to find and post a regulation/standard when writing about tires. If one is not willing to accept a standard that's their decision. Most that do not study industry regulations/stadards cannot string them together to make statements. The power of vehicle certification is squarely on the shoulders of the vehicle manufacturer. However, there are some trickle down parts that are passed on to consumers.

DOT - CFR part 567

[TitanMike]

What you fail to acknowlege is that when one replaces a tire with one that exceeds the load carrying ability an all the speed rating points you listed are moot.

Lawsuits occur when the load/speed capacity minimums aren't met, not when the load/speed minimum abilities are exceeded by the new tire.

Why no case law to support your assertions, where a lawsuit actually occurred because someone put a better tire with more load capacity and speed rating on their vehicle.

Good luck finding one.

BTW I actually worked in the tire and service industry for 36 years and am very familiar with how regulations apply to replacement tires. 17 of those years involved teaching Dealers andtheir employees on tires and "regulations".

Your insistance one must follow the exact size on the sticker makes as much sense as telling someone they need to consult the manufacturer before they substitute a Grade-8 bolt for a Grade-5 bolt of same size, thread pitch, and length.

[Airdale]

You, like many others have misunderstood my message. There is a right way and a wrong way. Many, like you, prefer to do it their way. When straying from the right way, one should tell their audience that is what they are doing.

Someone with a long time experience in the automotive tire business should well know there is a difference in the selection of replacement tires for RV trailers as opposed to automotive vehicles. Manufacturers of automotive vehicles provide the tire industry with a detailed listing of tires that are acceptable as replacements on vehicles they manufactured. The RV trailer industry relies on the vehicle manufacturer to approve/disapprove the selection of replacement tires they have manufactured. That procedure is simple and listed in the vehicle owner’s manuals.

The right or wrong with the selection of replacement tires for RV trailer fitments is squarely in the hands of the consumer. Many of them seek answers in forums like this one. I see no harm in providing the do and don’t do procedures found in the many regulations and industry standards.

Recalls are the product of insuring vehicle safety. A simple explanation of a recall for an incorrect RV trailer certification label can be the label had the wrong PSI for the manufacturer installed tires. Do you know there is a NHTSA supported label for recommended tire inflation pressures when they are changed during the fitment of RV trailer tire replacements?

I don’t shoot “from the hip”. I do my research wherever it takes me. The public library or large book store retailers have many publications about litigations, including tires. I have one as a reference to help me insure I’m not misquoting a regulation or standard.

[NavyLCDR]

TitanMike is right. Airedale is well.... Airedale. In order to lose a lawsuit regarding negligence, the claimant would need to prove by a preponderance of the evidence that the tires installed did not meet NHTA safety standards. The most critical factor being load rating. Your trailer comes with LRD tires and you put LRC on it.... you are toast. Trailer comes with LRD tires and you replace with LRD tires or better...regardless of size...you will likely prevail in a lawsuit, regardless of whether or not you obtained vehicle manufacturer's approval or not.

[Airdale]

Originally Posted by NavyLCDR

TitanMike is right. Airedale is well.... Airedale. In order to lose a lawsuit regarding negligence, the claimant would need to prove by a preponderance of the evidence that the tires installed did not meet NHTA safety standards. The most critical factor being load rating. Your trailer comes with LRD tires and you put LRC on it.... you are toast. Trailer comes with LRD tires and you replace with LRD tires or better...regardless of size...you will likely prevail in a lawsuit, regardless of whether or not you obtained vehicle manufacturer's approval or not.

Changing a load range on a designated size is not a size change.

Changing a designated size from the one on the vehicle certification label requires explanations as to load capacity and recommended inflation pressures.

Almost all tire manufacturers provide detailed procedures for 'plus sizing" tires. Bridgestone is my choice as it covers all aspects of the procedures.

Have you knowingly or unknowingly supported the following industry standard?

Replacement tires MUST provide a load capacity equal to or greater than the originally installed tires, via recommended inflation pressures.

Question: where does one find the recommended inflation pressures for plus sized tires? A plus sizing procedures manual will tell you.

[NavyLCDR]

Originally Posted by Airdale

Question: where does one find the recommended inflation pressures for plus sized tires? A plus sizing procedures manual will tell you.

Answer:
https://www.goodyearrvtires.com/pdfs/rv_inflation.pdf
Have a nice evening.

[Airdale]

Originally Posted by NavyLCDR

Answer:
https://www.goodyearrvtires.com/pdfs/rv_inflation.pdf
Have a nice evening.

Those are not recommendations. They are standardized tire inflation charts provided and approved by the Tire and Rim association (TRA). They are designed to be used by tire installers to insure tires meet the recommendation requirements from vehicle manufacturers. They are also used by installers of plus sized tires to insure the new recommended inflation pressures comply with the load requirements to insure the replacements provide the load capacity equal to what the OE tires provided.

[Mike134]

Originally Posted by Airdale

Those are not recommendations. They are standardized tire inflation charts provided and approved by the Tire and Rim association (TRA). They are designed to be used by tire installers to insure tires meet the recommendation requirements from vehicle manufacturers. They are also used by installers of plus sized tires to insure the new recommended inflation pressures comply with the load requirements to insure the replacements provide the load capacity equal to what the OE tires provided.

You strike me as the kid who just graduated college walking onto a building site and will tell all those guys in the various trades just how it should be done.

[Boomerweps]

Thank you everyone for your thoughts and concerns.
I’m not concerned over a one mild step upsizing on trailer tires. Far more radical changes are done daily on cars and trucks.
I’m most concerned over removing my wheels on a downslope in a gravel drive to swap the tires out. Might move it to a more level spot first that will block a lot of the drive with 5 drivers and 5 vehicles ;(