trailer wheel weight rating/compared to tire psi rating?

[MFL]

My 6-bolt wheels on 5200 lb axles with oem 225/75R 15 D-rated 2540 max wt tires. My wheels are steel and are marked 2,600 max weight. My FW GVWR is 12,110, which would mean 10K max on tires/wheels. I have a 4K CCC, so FW never loaded to GVWR. I am thinking not much more than 8,500 lbs on tires/wheels most times.

I am planning to replace the tires this Spring. My first choice is GY Endurance 225/75R 15E with max rating 2,830 at 80 psi. I understand that at 65 psi, these tires would carry same 2540 as current D tires.

My question is...if I inflate these new E-rated tires to 80 psi, giving the tires full load carrying capacity, will the wheels take that increase in pressure? I will replace the rubber stems, with 80 psi rated stems.

Any of you heavy commercial haulers ever break a steel trailer wheel from a bit over listed max weight?

Jerry

[BarneyS]

Ok, that' enough. I have better things to do rather than spend all day cleaning up this thread again.
barney

[Cummins12V98]

RV.NET Senior Member said: "Using the inflation chart to get the pressure for the load, I inflated to 80 psi which was good for 4500 pounds per tire."



HMMMMM, I wonder what chart he was using as this chart above 235/75 r17.5 "J" at 80psi only gives 4,210# capacity. Using this chart with a 4,500# load he would have needed 95psi per GY Tech Support.

Let's try 245/70 R17.5. HMMMM that only gives 4,110# at 80psi.

The 215/75 R17.5 highest load range is "G" and 80psi gives 3.135# capacity.

Looks like your person had no clue what they were doing??? Maybe provide the chart he used and tire size/load range.

Please correct me of i posted any incorrect info.

[Cummins12V98]

JIMNLIN said: "Over tiring a trailer 35% above 4500 lb wheel loads leads to speculations on the best air pressures for a 6008 lb rated 18 ply tire. I'll speculate maybe 110-115 psi at a minimum."

So funny no one can give a straight answer but have lot's of opinions. In your post you are quoting someone running 125psi on a 4,500# load but you are suggesting for me " I'll speculate maybe 110-115 psi at a minimum."

Now let's say I go by a 15% margin that many talk about. My load is 4,500# and adding 15% is 5,175#. So using the chart 105psi gives me 5,200# capacity slightly over the magical 15% reserve.

What say y'all ?

Not being "argumentative" here, I simply would like people to give straight answers or suggestions.

[StirCrazy]

I just caught up on this one. for me no matter what tire I am using if it is in a trailer aplication I use max PSI. two reasons which have been brought up, trailer tires are subjected more to sidewall flexing and scubbing, and the second better fuel milage, I guess there is a third. less of a chance of excessive internal heat generated. now on my truck if I know I am not going to be towing or hauling anything I will lower my rear tires for about 60 PSI. if I go by weight I could go to 40 psi but the tire company said not to go under 55 on them so I figured 60 was a nice round number. but if I am hauling I don't play around with 70 or 75 psi anymore just fill them to 80psi and have a bit of a saftey cushion.

Steve

[MFL]

Cummins12V98:

A very helpful post above, from JIMNLIN!!

While I'm not as familiar with heavy commercial tires, I agree with Jim's recommendation. I do remember the post he was quoting, and should be a great help with what you are asking. I will add, that running that tire near max psi, won't damage the tire. Running it lower, say 100 psi???

Nice of Jim to give his thought on the minimum pressure. I would trust his advice.

Jerry

[JIMNLIN]

This from a rv.net member found out from actual experience about low pressure = higher tire temps along with more rolling resistance when derating commercial grade G or H or J tires.

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***When it came time for me to replace our tires, I researched many different ways to go. I wound up purchasing 17.5" J rated medium duty truck tires and wheels. When all done and said, it was $5.00 per wheel and tire combo more than just replaceing the 16" tires. This tire and wheel combo is good for 6005 pounds each. Using the inflation chart to get the pressure for the load, I inflated to 80 psi which was good for 4500 pounds per tire. With the first tow with these tires to Kansas City, I have made this trip to the speedway several times before, I was down almost 2 mpg both ways. The tires were 20*-25* hotter than the truck, which I have never experienced before. I inflated them to the side wall pressure, 125 psi for max load, before our trip to Florida. Now the tires run 5*-10* cooler than the truck and my fuel mileage is back where it used to be. I have always run max pressure up until I installed these tires, with what I have experienced, I will continue to run what the side wall indicates.***

Now add expert advice from actual tire engineers on the subject of interply shear forces and internal carcass/tread belt damage ......and minimum pressure charts Tireman9 and Capriracer has tried to educate us for years.

Over tiring a trailer 35% above 4500 lb wheel loads leads to speculations on the best air pressures for a 6008 lb rated 18 ply tire. I'll speculate maybe 110-115 psi at a minimum.

[Cummins12V98]

WEIRD, I thought the thread was closed.

No arguing here, would like questions answered from Capri Racer and others as I have always felt he used commonsense in his comments.

My RV is a 2016 Mobile Suites that came with GY "H" 17.5's with 4,805@ 125psi. My factory weighed loaded wheel weight is around 4,500#. Finally decided to go to the Continental's HTL2 ECO Plus 235/75 R17.5 "J" 18 ply, many other HEAVY Mobile Suites tandem axle RV's are doing the same with good results. They are rated at 6,005# @ 125psi. The Alcoa wheels are rated at 6,050# that i changed to only because two of the OE were scuffed with the tire blowing out. Will be selling the GY's and wheels later this Spring.

So wondering what PSI others would recommend. I am thinking 100psi?

[BurbMan]

BarneyS wrote:
Come on folks, why so argumentative?

Not sure Barney....several folks (including myself) answered the OP's question yet the OP keeps saying the thread "went sideways". We're all just trying to help here.

[cummins2014]

MFL wrote:
eHoefler wrote:

"You have to replace the wheels to accommodate the higher pressure."

This man answered my question, right away, on first page. Not what I wanted to hear, but I think likely the correct answer.

My thread went off the track, turned foolish at one point. I may have hurt some feelings, trying to keep it on track. Hope not!!

I will answer CumminsV12, as to my tire edge wear from scrubbing, which is already described in my post on page one. Several of my tires show tread wear, on the edges mostly from my tight backing/severe side scrub, at home. I will not describe, but the black marks on my concrete driveway tells the story, as does my visible twisted wheels/suspension.

As to the tire inflation chart tire pressure, Capri was correct, a minimum. Using these minimum inflation charts, is not a one size fits all. They have charts for all types of tires. Truck tires, MH tires, single axle tires, not the same as an RV with tandem, or triple axles.

For FW tandems like mine, and some triples, also TTs, you can weigh your trailer, to get actual weight on tires, look at the RV specific chart. Now to find a very minimum, add 10% more air, could be 5 lbs maybe 10, but use 10%. Now that is a minimum, using 20% is better, if not going over sidewall max. Best of all, unless you have way more tire than needed, is to just inflate to sidewall max, for best protection from tire damage.

An ST tire gets it's strength from air pressure. To protect the belts, and avoid ply separation issues, from severe scrub, more air is better, all the way to max sidewall pressure, is recommended.

This post is not what my thread was about, but I feel is an important issue. If someone would start a new thread, maybe over on general, others may chime in with their thoughts.

Jerry

We went thru all this back around 2009 on the Montana forum . Many of us had the new Montana fifth wheels with the china bomb tires on them . Most wanted to go to the Goodyear G614's , about the only game in town for a G rated tire back then . I had alloy wheels on my new 2008 Montana fifth wheel, that had no weight or psi rating on them , as many of the other Montana owners had . Anyway someone got with wheel manufacturer , and they sent us all a sticker with a 110 psi, and 3750 lb rating to stick on the wheels . That was all all fine ,and dandy , and so some of us went with the G614's . Well the wheel manufacturer decided to change their minds after the fact , I am sure it was a CYA after giving it some thought .

Anyway , I ran those wheels up until two years ago with G rated tires ,and 100-110 psi , no problems , as did many others . Thats my two cents worth. 🙂

[BarneyS]

Come on folks, why so argumentative? This forum is for information and enjoyment - not for fighting and arguments. Disagreements are fine as long as they stay civil and not get personal. That way, we all learn something and have fun also!:B
Barney

[CapriRacer]

Cummins12V98 wrote:

CapriRacer wrote:

Cummins12V98 wrote:
..... I would like someone to explain whey they have weight inflation chart for the ENDURANCE if it's not ok to run tires pressures based on actual load. ......

Those are MINIMUMS, not recommendations.

Sure but that is what the tire is designed to support at those pressures right? .....

Yes, but just barely. Not a good practice.

Cummins12V98 wrote:
.....Maybe you can elaborate. Do you disagree with GY tech support or agree that a person up sizing in load range can use the chart for the best ride, tire wear and stopping by adding 5psi to the chart. .....

I am merely saying that the tables are a minimum, not a recommendation and it looks like the GY tech support agrees with me.

Cummins12V98 wrote:
...... Let's forget Jerry's rim pressure rating. If you went to the GY "E" 15" would you run the tires at 80psi or use the chart plus 5psi as GY Tech recommends? .....

I would need some additional information. Like year, make, and model of trailer. What does the vehicle manufacturer specify? Are actual weights available?

In other words, the sort of thing a vehicle manufacturer would go through when they make their specification.

Yes, we know that some trailer manufacturers didn't do a good job of specifying tires and pressures. Is Jerry's vehicle one of them? Do we have reason to disagree with their specification?

These are all questions that I would need to make a recommendation.

Cummins12V98 wrote:
..... Answer this. I am around 4,500# load on each tire and the GY "H" tires were not holding up running them at 125psi with a rating of 4,805#. Now I went with the Continental's with 6,005# rating at 125psi. Would you run 125 psi or lower pressure like 100 that gives 5,200# capacity?

Why so argumentative?
But to answer your question, see the above for how I would do it. Your question doesn't contain the information I would seek before giving an answer.

[MFL]

eHoefler wrote:

"You have to replace the wheels to accommodate the higher pressure."

This man answered my question, right away, on first page. Not what I wanted to hear, but I think likely the correct answer.

My thread went off the track, turned foolish at one point. I may have hurt some feelings, trying to keep it on track. Hope not!!

I will answer CumminsV12, as to my tire edge wear from scrubbing, which is already described in my post on page one. Several of my tires show tread wear, on the edges mostly from my tight backing/severe side scrub, at home. I will not describe, but the black marks on my concrete driveway tells the story, as does my visible twisted wheels/suspension.

As to the tire inflation chart tire pressure, Capri was correct, a minimum. Using these minimum inflation charts, is not a one size fits all. They have charts for all types of tires. Truck tires, MH tires, single axle tires, not the same as an RV with tandem, or triple axles.

For FW tandems like mine, and some triples, also TTs, you can weigh your trailer, to get actual weight on tires, look at the RV specific chart. Now to find a very minimum, add 10% more air, could be 5 lbs maybe 10, but use 10%. Now that is a minimum, using 20% is better, if not going over sidewall max. Best of all, unless you have way more tire than needed, is to just inflate to sidewall max, for best protection from tire damage.

An ST tire gets it's strength from air pressure. To protect the belts, and avoid ply separation issues, from severe scrub, more air is better, all the way to max sidewall pressure, is recommended.

This post is not what my thread was about, but I feel is an important issue. If someone would start a new thread, maybe over on general, others may chime in with their thoughts.

Jerry

[time2roll]

Cummins12V98 wrote:
what should I inflate my 6,005# tires to that the load is 4,500#????????? Don't seem to be getting an answer?????

I would go chart + 5 to 10 psi not to exceed the sidewall max if it is an LT or P tire. If the low weight is not on the chart I would use the lowest shown + 5psi. Run the sidewall max with an ST unless the ride seems stiff or bouncy. If there is a ride issue reduce to the chart +5.

[Cummins12V98]

Less weight on a tire is less force "scrubbing" I would not run a D tire at lower than max if that is what the tire weight is. If I did there would be more "scrubbing" and more chance of damage. A heavier tire will handle more stress even at lower pressures as long as the weight isn't over the inflation rating.

Simple common sense here folks.

So you EXPERTS what should I inflate my 6,005# tires to that the load is 4,500#????????? Don't seem to be getting an answer?????

NO mention of any 50% capacity from GY Tech support. I guess they have no idea what they are talking about.

Maybe one of you can tell Jerry why the outer edges of his tires are wearing much more than the rest of the tire??? No way it's from scrubbing, unless the tread compound is so poor it just peels off. Don't think that is so because he has gotten lots of miles on them.