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Old 08-25-2022, 06:01 AM   #21
bsmith0404
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Here we go again. The debate of tire load range, load index, tire size, tire psi just never gets old and each discussion goes over the same info. The difference between load range D and E is the tires added strength/ability to hold air. The air caries the weight. So using 65 psi as what’s on the sticker on the rv basically gives you the same load carrying capacity as an LRD, no advantage of moving up to an LRE. The 80 psi that is on the sidewall of the LRE tire gives its max carrying capacity, in most cases with an LRE that will be around 2800 lbs. Anything less than the max 80 psi will reduce the capacity of that tire. Some believe you should always run max psi and there are strong arguments for that. I’ve even seen in writing some where that trailer tires should always be run at max psi. I don’t remember where or who wrote it, and personally, don’t care. Some believe you can or should reduce the pressure to give a better ride. I believe it depends.

For example, my 5er weighs 14,200 lbs loaded with 2800 lbs on the pin so 11,400 on the tires. In theory, I only need 2850 lb capacity per tire. However, that doesn’t account for things like uneven loading, loss of air pressure, tire degradation with age, etc. so you always get a tire with reserve capacity. It’s recommended/mandated by the tire industry to have at least 10% reserve. The tires I have are rated for 4400 lbs at 110 psi. That’s a total capacity of 17,600 lbs with a reserve of 1,550 per tire, 6,200 lbs total. (Those numbers are less if I used the 15,500 GVWR, but I use the actual loaded weight of my rv for my calculations). The problem I have is that I have so much, almost too much reserve capacity. The tires balloon up in the center and I get uneven wear. Because of that, I reduce the cold psi to 95 which still gives the tire 4000 lb capacity. That is still more than enough reserve for my situation. Some people agree with that, some don’t. Personally, it’s my rv, my tire, my money. What others may think doesn’t really matter. With the weights you have, if it was mine, I’d get the LRE and run them at max sidewall pressure of 80 psi, but that’s just my opinion. What you do with your rv is your choice.
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Old 08-25-2022, 06:21 AM   #22
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The "point I was trying to convey" is that if someone changes tires on their trailer and UPGRADES (either tire size or load designation) then the information on the side of the trailer still reflects THE OLD TIRE INFORMATION, not the new tire information. You'll need to use the NEW TIRE INFORMATION for the new tires. Don't rely on the trailer decal because those tires are no longer on the trailer and the new tires have different load ratings, different pressure requirements and different performance characteristics....

That's the part that many "experts" seem to forget: THE TIRES ARE UPGRADED AND DON'T PERFORM EXACTLY THE SAME AS THE OLD TIRES !!!!!

Don't treat them like the old tires or you lose any "upgrade capacity" from the increased pressure capacity, increased load capacity and lose the reason you bought "upgraded tires".....
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Old 08-25-2022, 06:30 AM   #23
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Quote:
Originally Posted by bsmith0404 View Post

It’s recommended/mandated by the tire industry to have at least 10% reserve.
That 10% recommendation comes from the RVIA organization. It has nothing to do with tire industry standards.

There is a simple formular all RV trailer builders MUST comply with for original equipment tire fitments. (The vehicle manufacturer's recommended tongue weight, when added to the vehicle's total GAWRs must not be less than GVWR). Therefore, OE tires must provide a load capacity equal to the vehicle certified GAWRs.

I'm adding an older Keystone certification label to show just how far Keystone would go to use tires equal to the GAWRs they have certified.

Click image for larger version

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ID:	41385

This is an excerpt from the FMVSS standards the RV trailer manufacturer must apply for OE tire selections. "The sum of the maximum load ratings of the tires fitted to an axle shall be not less than the gross axle weight rating (GAWR) of the axle system as specified on the vehicle's certification label required by 49 CFR part 567."
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Old 08-25-2022, 06:31 AM   #24
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Amen! to what John said. I stand corrected on who mandates the 10%
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Old 08-25-2022, 06:54 AM   #25
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Originally Posted by JRTJH View Post
The "point I was trying to convey" is that if someone changes tires on their trailer and UPGRADES (either tire size or load designation) then the information on the side of the trailer still reflects THE OLD TIRE INFORMATION, not the new tire information. You'll need to use the NEW TIRE INFORMATION for the new tires. Don't rely on the trailer decal because those tires are no longer on the trailer and the new tires have different load ratings, different pressure requirements and different performance characteristics....

That's the part that many "experts" seem to forget: THE TIRES ARE UPGRADED AND DON'T PERFORM EXACTLY THE SAME AS THE OLD TIRES !!!!!

Don't treat them like the old tires or you lose any "upgrade capacity" from the increased pressure capacity, increased load capacity and lose the reason you bought "upgraded tires".....
This is a tire's designated size and load range; ST225/75R15 LRD
This is a tire's designated size and load range; ST225/75R15 LRE

Both provide identical load capacities at 65 PSI from the same tire load and inflation chart.

Designated tire sizes do not change because of load range changes. However, there is no assurance the OEM wheels will be equipped with valve stems needed to provide a higher PSI rating or that the wheels will have a load capacity rating for higher load ranges.

When available, a tire's designated size may have some higher load ranges. The vehicle certification label doesn't care what load range is used as long as it complies with the minimum standards on the label. Everything greater than the minimum requirements is optional - as long as the designated size is maintained.
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Old 08-25-2022, 07:01 AM   #26
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The OP has already verified his wheels are rated for 2830 and can handle the LRE in the same size as his OE LRD. I’ve never seen a tire shop that doesn’t install new high pressure valve stems when they install new tires. However, it’s been recommended that he switch to steel valve stems and get a TPMS.
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Old 08-25-2022, 07:04 AM   #27
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The OP did ask if he could go from LRD to LRE and the answer has been given multiple times. Yes. With LRE the tires have a high load capacity which seems like a good idea for his trailer's gross weight as stated. I also mentioned metal valve stems and TPMS. I hope the confusion ends fairly soon and stating standards technicalities seems to predominate these threads but don't answer the question asked. Thanks. I think this thread has been beaten to death.
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Old 08-25-2022, 07:31 AM   #28
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The "dust" is blowing! The OP wants to upgrade tires. The sticker on the trailer no longer applies other than it shows what came OE and the minimum weight carrying ability of the tires. The size is there as well. Once the OP decides to upgrade his tires the certification label loses nearly all relevance for the most part. The reason for the upgrade is to gain capacity reserves over the designated OE tires because they are generally insufficient IMO. Same size tire, upgraded load range to gain reserves, air to 80psi for the new load range to gain those reserves which the wheel will support, add metal valve stems and a TPMS, ignore the load range and inflation pressure on the certification label...simple and easy - there's is no reason to stir up "dust" over that.
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Old 08-25-2022, 08:32 AM   #29
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Oh mercy, blah, blah, blah, just constant regurgitation of the same information, quoting the same regulations (often out of context for the question or subject at hand) and more "expert gyrations".

How many here vote to change the discussion. Maybe plain vs peanut M&Ms? Coke vs Pepsi? Mounds vs Almond Joy?
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Old 08-25-2022, 08:34 AM   #30
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Thank you bsmith0404.
Could you recommend a TPMS for my trailer tires, I have done some research on some of the different systems, but haven't chosen the system I want to purchase yet. This will be my first purchase of a TPMS.
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Old 08-25-2022, 08:42 AM   #31
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Quote:
Originally Posted by edeman View Post
Thank you bsmith0404.
Could you recommend a TPMS for my trailer tires, I have done some research on some of the different systems, but haven't chosen the system I want to purchase yet. This will be my first purchase of a TPMS.
I'm not who you ask!
But can highly recommend the TST507, works great, user replaceable batteries, provides pressure/temperature info & great customer service if needed.
Metal valve stems will be required for the heavier load rated tires & TPMS sensors.
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Old 08-25-2022, 09:11 AM   #32
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Originally Posted by edeman View Post
Thank you bsmith0404.
Could you recommend a TPMS for my trailer tires, I have done some research on some of the different systems, but haven't chosen the system I want to purchase yet. This will be my first purchase of a TPMS.
I’ve been using TST 507 for nearly 10 years now. It has worked flawlessly and saved me twice. I’m actually on my second system, gave the first one to my dad. If I was buying again today, it’d be another TST 507 system, no doubt about it.
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Old 08-25-2022, 12:50 PM   #33
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I'm just going to make this perfectly clear with a one liner.

The OP is not going to invalidate his vehicle certification label with a load range increase.
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Old 08-25-2022, 03:38 PM   #34
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I'm just going to make this perfectly clear with a one liner.

The OP is not going to invalidate his vehicle certification label with a load range increase.
I was going to ask if the OP tore the label off his mattress would that invalidate the vehicle certification?
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Old 08-25-2022, 05:49 PM   #35
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I was going to ask if the OP tore the label off his mattress would that invalidate the vehicle certification?
No, probably not, at least in North Carolina or Michigan or Louisiana. There are some states (not Texas) where who knows if it is still considered a crime to rip a mattress tag off a mattress... That "Under penalty of law" tag scares some people "nearly to death" and then there's those "rebels who live on the edge" and are willing to rent a room in an undisclosed Hampton Inn and undo the sheets to search for mattress tags that might still be on a mattress in an "rented hotel room"... Now that's really "taking the risks to the extreme"... Probably much like this thread has taken tires to the extreme !!!!!
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Old 09-08-2022, 07:42 AM   #36
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I completely disagree with your last statement. On my second set of Carlisle Radial Trail HD and went from D to E rating. Tires did and are wearing even. If you run an E rated tire at D rated pressure then what's the purpose of going up a rateing? It's the air pressure that supports the weight.
I agree. Came with ST235/80R16 and went to Sailon E rated tires. So much better!
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Old 09-08-2022, 12:32 PM   #37
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I completely disagree with your last statement. On my second set of Carlisle Radial Trail HD and went from D to E rating. Tires did and are wearing even. If you run an E rated tire at D rated pressure then what's the purpose of going up a rateing? It's the air pressure that supports the weight.
Go up to the E Load Range, some advice is to go to Goodyear Endurance and avoid the China Bombs. Be sure to note the pressure change to 80 PSI and the wheel will work fine. You can check if you wish. Biggest advantage is Peace of Mind.
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Old 09-08-2022, 01:40 PM   #38
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Hello everyone,
I have a 2017 Keystone Springdale 5th wheel SG253 about 10K or so weight.
Currently my tire size on the trailer are ST225/75R15 Load range D (65) and I need to purchase new tires. Would it be better to purchase Load Range E or stay with LR D.

Thank you.



"about 10K or so weight" suggests that you do not know the actual load on each tire or even on each axle. With data showing the majority of RV having a tire or axle in overload people need to stop guessing about this important safety item.


Going to LR-E and increasing inflation till your tires can support at least 110% of the actual load on them will reduce the chance of having a tire failure.
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Old 09-08-2022, 01:42 PM   #39
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No matter what tire you choose, follow the trailer manufacturer's load rating, even if the tire can handle more.

Running the tires at a pressure higher than needed will lead to a shorter tire life.



Not sure if I understand your claim of "shorter life". Given that RV trailers usually "age out before they wear out I would not be concerned about the potential of faster wear.
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Old 09-08-2022, 01:44 PM   #40
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We will agree to disagree on that one.



Are you saying that it is not the air pressure that supports the load? I think that a review of the Load & Inflation tables available on tires shows the relationship between load capacity and inflation pressure.
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