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Old 09-09-2018, 12:21 PM   #161
Javi
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Originally Posted by CWtheMan View Post
No one in the tire industry or even the governing body has a grip on tire aging. Some even ponder the "don't use after 10 year mark".

IMO the best ballpark figures will come from the manufacturer of the tires you're using. Each seem to have different variations.

In my research I found that Carlisle Tire, way back when, were the sort of spokesperson for the ST tire design. Others were soon to follow and the 3-5 year useage became a sort of standard for those tires.
I understand that.. again, I was rebutting your buddy's claim that LT tires last longer than 10 years when used in RV trailer fitments...

Personally, I'm not going to use my ST tires past 2 years and the LT tires longevity past 3 or 4 years is moot to me for my application, because I wear the tread to minimum before that..

I did enjoy the way he melded the two different test results to provide backup to his contention that LT tires should replace ST tires regardless of rule/law or policy... it was inventive..
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Old 09-09-2018, 12:49 PM   #162
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Originally Posted by Javi View Post
So far I have not seen irrefutable evidence to support the assertion that I break the law/rules or policies in the tire industry by mounting tires which have less load capacity than the O.E.M. fitment... [/COLOR]


I'm waiting...
I often write about that subject. Most will not take the time to do a complete research. Out of context info will become overbearing and vary misleading without a complete knowledge of how all the factors, when tired together, cause the entire tire industry to determining the vehicle manufacturer’s selection of the original equipment tires sets the minimum standard for your vehicle, car, truck or trailer.

NHTSA and the tire industry are in complete agreement that the following statement is the standard to be met when selecting replacement tires.

“Replacement tires must be the same size designation as the Original Equipment tires or others recommended by the vehicle manufacturer. They must provide a load capacity equal to or greater than the OE tires provided at the vehicle manufacturer recommended cold inflation pressures.”

This may already be in this thread but I’ll post it again here. It’s a sample of how some of the major tire manufacturers say it.


Goodyear: Never fit tires to a vehicle that have less load carrying capacity than required by the Original Equipment Manufacturer.

Michelin: Never choose a tire that is smaller in size or has less load-carrying capacity than the tire that came with the vehicle.

Cooper: The new tires must have a load carrying capacity equal to or greater than the maximum load carrying capacity specified on the tire placard on the vehicle.

Toyo: Any replacement tire must be of a size and load range that will offer equal or higher load carrying capacity compared to the original equipment (OE) tire on the vehicle.
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Old 09-09-2018, 01:32 PM   #163
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Originally Posted by Javi View Post
Give me an LT tire in a 235/85/16 that provides 3500 lbs. or more of documented load capacity at my wheel limit of 80 pounds and I'm all over it.. or for that matter find me a 16" x6 rime with a 6 on 5.5" pattern and I'm all over that too... I just don't want to spend several thousands of dollars to replace axles and equipment to do it.. I'd rather just wait and buy a trailer equipped with 7K axles...
In the evolution of tires it has become necessary to better describe the tires in use. Before the internet became saturated with tire information, people in the industry knew what a tire size was without complete instructions. About 5-7 years ago a more formal tire description was introduced. When reading newer information that includes tires size descriptions you will find them identified as "designated size". A tire's designated size is like these two examples. ST225/75R15 or LT235/85R16 are designated sizes. The prefix is part of that size designation thus, it includes a design. Those two designs have their load capacities described by the load range lettering system.

The size designation becomes a factor when complying with the replacement tire selection recommendations to use tires like the OE tires. A well trained tire installer is not going to replace a ST tire with a LT tire, even of the same physical size.
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Old 09-09-2018, 04:51 PM   #164
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Originally Posted by CWtheMan View Post
I should have elaborated. All the tires I buy for my trucks and cars are available with a road hazard warranty. But not ST tires or even LT's if you are installing them on an RV or trailer. I was told this at the Firestone store and at Walmart.
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Old 09-09-2018, 05:49 PM   #165
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I use to feel sorry for people forced into ST tires by the overt market of the product. HOWEVER with the effort Goodyear put into the new Endurance and it's record to date, maybe all is not lost. Ever I purchased a set to replace the china bombs that came on the new Laredo.

This does not however make up for all those that suffer damage, loss of use and cost associated with all the ST failures over so many years.

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Old 09-28-2018, 10:11 AM   #166
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Originally Posted by rhagfo View Post

Our 2005 Copper Canyon came with LT 235/85-16Es even though my GVWR is 12,360. Being a 2005 I don't have the yellow sticker, just the VIN weight statement inside a cabinet door near the sink, where it holds up a lot better!
I do have an email from Keystone with the build information that states LT 235/85-16s were installed at the factory.

Just saying.
Russ

If you're referring to the vehicle certification label, I can assure you there was supposed to be one. The manufacturer’s certification label for trailers must be affixed to a location on the forward half of the left side, such that it is easily readable from outside the vehicle without moving any part of the vehicle.

On our 2003 Everest it was located on the left side forward basement door.


It was a clear violation for Keystone to sell your trailer without the certification label. There is no provision to place it anywhere other than directed by NHTSA.


My research files are quite extensive. More information about vehicle certification and equipment certifications can be found in the following PDF.

I can't get the PDF file to a place to copy. You'll have to put this information in your search engine....REQUIREMENTS FOR MANUFACTURERS OF MOTOR VEHICLES AND MOTOR VEHICLE EQUIPMENT
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Old 10-01-2018, 10:29 PM   #167
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Just finished reading this entire thread. Lot of good information. I recently got the truck and trailer in my sig both new (2018 GMC 2500HD Denali Diesel and 2018 Hideout 28RKS). Haven't taken it out yet.

For my trailer, it has the following stats:
GVWR: 9660#
Hitch Weight (minimum?): 860#
Max Cargo Payload: 2650#

There are 2x 4400# Axles on it, which is why the hitch must be 860 to satisfy the regulatory stuff (2x4400+860=9660). I have not taken anything onto a scale yet to verify what the actual hitch weight is but I currently have a 1000# WDH on the truck (what Camping World provided with the trailer - think it is a rebranded Curt) and the truck can take up to a 1500# tongue weight (Class V hitch receiver).

The factory installed tires are ST225/75R15 LRD rated at 2540# each @ 65 PSI (which is also what is on the sticker). Combined that gives me 10160# on the tires but only 8800# on the axles. I believe the trailer was around 7000# empty so when I load it up my understanding is I need to keep it closer to the front/hitch and not have any weight added over the axles if I can avoid it. Pretty much once the kitchen is stocked stick to the pass-through storage under the front. Fortunately, I can put a bunch of stuff in the truck bed to help offload the trailer while on the highway. The tires are LoadStar Karrier KR35 which looks like they are made by Kenda and have no speed rating stamped on them. Should I assume they are only rated for 65 mph then? These are definitely "Made in China" tires but based on the vast experience of everyone here, should I start looking for new tires or get a couple years use out of these before starting to worry?

Everything else was background, the bolded stuff is my most pressing concern. Ideally I would have tires rated up to ~80 mph for the trailer - is that realistic/reasonable? In my daily driver (just a Mazda CX-9) I regularly drive up to 10 over the speed limit and never more than 78-79 (got enough speeding tickets as a youth to have gotten that out of my system). I know I wont be going as fast in the truck pulling the trailer but would think that 70-75 is not outside of the realm of possibility especially in good conditions with low traffic.

And I do not know if this would be considered off topic or not...my truck has Goodyear Wrangler SR-A LT265/60R20ES tires installed from the factory. The GMC sticker calls for 60 PSI on the fronts, and 75 PSI on the rears. Goodyear specs the tires at 3195# load @ 80 PSI. My rear GAWR on the truck is 6200#. The front GAWR is 5200#. I have been unable to find an inflation/load chart for these tires - should I be good sticking to the sticker spec'd inflation pressures?

Thanks in advance for the help!
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Old 10-02-2018, 01:00 AM   #168
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Originally Posted by cookinwitdiesel View Post
...I can put a bunch of stuff in the truck bed to help offload the trailer while on the highway.

Whoops! Hold on a minute.


Remember that a WDH means weight distribution? That hitch doesn't just re-distribute the weight only one way. It also re-distributes the weight in the back of the truck back onto the trailer too. Have a look at this video. Dave talks about single axle trailers, but weight distribution is weight distribution no matter how many axles you have.
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Old 10-02-2018, 05:30 AM   #169
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Originally Posted by cookinwitdiesel View Post

The factory installed tires are ST225/75R15 LRD rated at 2540# each @ 65 PSI (which is also what is on the sticker). Combined that gives me 10160# on the tires but only 8800# on the axles. I believe the trailer was around 7000# empty so when I load it up my understanding is I need to keep it closer to the front/hitch and not have any weight added over the axles if I can avoid it. Pretty much once the kitchen is stocked stick to the pass-through storage under the front. Fortunately, I can put a bunch of stuff in the truck bed to help offload the trailer while on the highway. The tires are LoadStar Karrier KR35 which looks like they are made by Kenda and have no speed rating stamped on them. Should I assume they are only rated for 65 mph then? These are definitely "Made in China" tires but based on the vast experience of everyone here, should I start looking for new tires or get a couple years use out of these before starting to worry?


Thanks in advance for the help!
This is what I did!

I took our brand new 2019 Laredo 225MK (8K GVWR) to Discount Tire and replaced the Goodride ST225/75R15D's with Goodyear Endurance ST225/75R15E's and never looked back. Our trailer has the same 4400 lb axles. My wheels are rated to 80 PSI and I chose to inflate the LRE tires to 71 PSI.

I sold the 4 OEM tires on CL for 200 bucks in one day.

Chris
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Old 10-02-2018, 07:06 AM   #170
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Should I assume they are only rated for 65 mph then? These are definitely "Made in China" tires but based on the vast experience of everyone here, should I start looking for new tires or get a couple years use out of these before starting to worry?

I believe inexpensive tires will have been made inexpensively. They may last a season or even two. Or, they may come apart on your first trip out. The quality control just isn't there for the majority of these cheapo tires. All Keystone is worried about is meeting the minimum federal specs and whether the unit makes it to the dealer's lot. After that it's your problem. Most blowouts are the result of poor inflation, speed and tire age. A good tire will offer a little more forgiveness where a cheap tire may fail more easily and often. If you realize you are on borrowed time with the original tires and monitor the pressures "religiously" keeping the speed down, you might get through a season allowing the checkbook to heal up after such an initial major purchase.
That said, you have made a huge investment in your RV combo. For another few hundred dollars you can protect that investment by installing a set of "quality" tires. You can look on line at the results of having a trailer tire blowout at high speed. It ain't pretty and it sure as heck ain't cheap. Also, invest in a Tire Pressure Monitoring System (TPMS). Well worth the cost in peace of mind and repair expense since you'll be able to know if a tire is in trouble before it blows. Our TPMS saved our vacation and I'd never tow without it.

As for towing speed, I cruise at around 65 mph. If I need to pass, I'm perfectly comfortable bumping up to 75 to safely get around slower traffic.
Just an example of speed vs time on the road, Let's say I limit my cross country driving day to around 8 hours. And, I get about 300 miles per tank of fuel. At this rate I'm stopping at least twice. At 65mph it takes about 4.5 hours to cover the 300 miles. At 75 mph it's 4 hours. 30 minutes difference doesn't mean that much to me. Arriving safely and less stressed does. Let's face it you've got 5 tons of trailer chasing that Duramax. It's a whole different set of driving dynamics compared to driving a passenger car.
Further, I find with the Cougar, I'm using more 2 lane highways than freeways any way. Our motto :When there's a choice, always take the scenic route"!
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