Looking for tires

[CWtheMan]

Originally Posted by jadatis

Is it realy needed to upgrade, give GVWR, GAWR's and howmany axles, or better weighed axle- load, even better axle-end weights , in the loading you go on trip.

Then I will calculate for you.

What is there to calculate? Original Equipment designated tire size is displayed in three areas; the vehicle certification label, the vehicle owner's manual and on the tire/load placard. GVWR is not in play with RV trailer tire fitments.

The OE tires are deemed by any and all standards as the minimum acceptable designated size. Replacement tires can be from the same designated size and have an increase in load range without invalidating the vehicles tire designations. Larger tires are what is called "plus sized" tires and their use requires updating all references to the OE tires and a new recommended cold inflation pressure set. It MUST cause the tire to provide a load capacity equal to or greater than what the OE tires provided.

Please remember that I'm referencing minimums here. Any optional inflation pressures used by consumers must fall between vehicle manufacture recommendations and tire manufacturer maximum as displayed on the tire.

[jadatis]

The recomanded pressures and tires are not given here. GVWR is needed to yudge howmuch reserve is taken by the maker.
Seen airstreem TT with tires with large reserve, so upgrade not needed. But many TT and 5thW are provided with tires only yust enaugh to cover GAWR , so that is why I want to have all that info.

My care is to have enaugh reserves to laws of nature, wich rule above all recomandations.

Topicstarter can give all the info, and I will give my conclusions. Then he can do with it what he thinks is wise.

[Dallasrules]

What is a 129l tire

[jadatis]

I assume you read the service-descriptions, is loadindex and speedcode.
Li 129 is maxload 1850kg/4080 lbs
Speedcode L is max allowed speed of tire 120kmph/ 75mph.

[Dallasrules]

I am assuming then that is more than a G. What is a G rating = to?

I have the same issue as the poster. I have a 2010 coachmen 5th wheel I just bought. It has gy marathon 80 PSI tires. That's an E rating right? One tire only had about 35 lbs of air and I noticed small cracks. When it was inflated you couldn't see them any more, but now I know they are there. Plus, I don't know the age of the tires and the trailer is about 15k gvwr, so I think the E tires are not enough.

[jadatis]

E-load AT 80 psi LRE
F-load AT 95 psi LRF
G-load AT 110 psi LRG
But loadrange together with the sises and speed for wich maxload is calculated, makes the maxload/loadindex.

But assuming your tires 129L and 2 axles 4 tires.
16k minus 10% on pin/plate gives 14400lbs on the 4 tires needs 3600lbs a tire with zero reserve, not adviced .
In case of ST 30% reserve needed is 4680 lbs maxload needex to my standards. You now have ( I think) 4080 lbs a tire so then poor reserve.

In case of LT speedcode L a little less reserve needed, so still poor reserve, and upgrade to F-or G-load would be adviced to my standards, for what they are worth.

[CWtheMan]

Originally Posted by Dallasrules

I am assuming then that is more than a G. What is a G rating = to?

I have the same issue as the poster. I have a 2010 coachmen 5th wheel I just bought. It has gy marathon 80 PSI tires. That's an E rating right? One tire only had about 35 lbs of air and I noticed small cracks. When it was inflated you couldn't see them any more, but now I know they are there. Plus, I don't know the age of the tires and the trailer is about 15k gvwr, so I think the E tires are not enough.

You're right, move up to LRF of LRG. You'll most likely also have to replace the wheels and valve stems.

[Dallasrules]

Ok, so what's the difference between light truck tires and trailer tires?

[JRTJH]

Originally Posted by Dallasrules

Ok, so what's the difference between light truck tires and trailer tires?

It starts with different tire sidewall and tread base construction, different components and probably different rubber compounds as well as tread patterns.

Then there's Licensing and intended use. ST tires are "for trailer use only" and many LT tires are "not intended for trailer use".

Then there's size/pressure/capacity differences. A LT235 75R16 LRE at 80 PSI will not carry the same load as a ST235 75R16 LRE at 80 PSI and will probably have a significantly different speed rating. They are two different tire construction techniques that are intended for different tasks.

[Dallasrules]

[QUOTE=Make sure the wheels are rated for 110psi if you do; mine were.[/QUOTE]

I can't find a PSI rating on the wheels. I found 3 sets of marks. 513483 18x6J, max load 3580 lbs, ETO 09 followed by what looks like some hash marks.

I can go with load range E 124. Es are what it calls for, but it doesn't leave much to spare. Gvwr is 15k - 2500lb supposed pin weight. Axels are rated at 6830 each.

I would like to go to LRFs, but can't figure out if the wheels are rated for it.

[sourdough]

Your wheels are not rated for the F load (3860) and pressure of 95psi.

[Dallasrules]

Thanks. Couldn't find that anywhere

[wiredgeorge]

Danny! Noticed you said to use a compressor capable of 110 PSI (that would be the desired PSI for LRG). Not so much the compressor but the air regulator. My heavy duty work compressor will do well over 160 PSI but the Hausfeld Campbell cheapo regulator I use won't do 80 PSI reliably so I end up using my little 4 gallon Dewalt (oil-less) where the accurate regulator goes much higher. I will say that I have a Harbor Freight little oil-less compressor (probably used for nail guns) and it says it goes to 160 PSI but will NOT fill 80 PSI so if I drag a compressor on a camping trip, it is the Dewalt. The HF compressor cost like $30 on sale and is pretty much useless for most anything.

[Tireman9]

Originally Posted by ChuckS

With the weight of that High Country fifth wheel E rated tires are a joke.. G rated 14 ply tires would be all I’d have... period

Verify what your wheels are rated at for psi ( stamped on backside of wheel usually) and run only all metal valve stems

For me the tires of choice are..
1. Sailun S637 series
2. Hercules 901 series

Both excellent tires and will give you many miles and years of trouble free towing if kept inflated properly, covered to minimize UV damage, and common sense towing speeds of 62 to 65 mph

My current 14 ply tires are now 5 years old.. I have no intentions of replacing yet and I am not worried about them...

Goodyear G614 is a nice tire but it’s expensive as the devil and the load capacities aren’t as good as the ST rated G series tires


YMMV

Not sure if "good" is the best word to use when you are comparing different type tires. All ST type tires have a higher load capacity that any LT type tire of the same dimensions at the same inflation. This is a function of the load formula used for ST type tires. A different formula does not make any tire "better" or another not as good when you try and compare different type tires.
Different yes. Higher or Lower load capacities yes but not Better or not as good.

[travelin texans]

Originally Posted by wiredgeorge

Danny! Noticed you said to use a compressor capable of 110 PSI (that would be the desired PSI for LRG). Not so much the compressor but the air regulator. My heavy duty work compressor will do well over 160 PSI but the Hausfeld Campbell cheapo regulator I use won't do 80 PSI reliably so I end up using my little 4 gallon Dewalt (oil-less) where the accurate regulator goes much higher. I will say that I have a Harbor Freight little oil-less compressor (probably used for nail guns) and it says it goes to 160 PSI but will NOT fill 80 PSI so if I drag a compressor on a camping trip, it is the Dewalt. The HF compressor cost like $30 on sale and is pretty much useless for most anything.

Guess I should've stated compressor &/or regulator. My buddy bought a compressor I think at Walmart that max pressure was 80 psi, useless for heavy load range tires.

[gearhead]

Originally Posted by wiredgeorge

Danny! Noticed you said to use a compressor capable of 110 PSI (that would be the desired PSI for LRG). Not so much the compressor but the air regulator. My heavy duty work compressor will do well over 160 PSI but the Hausfeld Campbell cheapo regulator I use won't do 80 PSI reliably so I end up using my little 4 gallon Dewalt (oil-less) where the accurate regulator goes much higher. I will say that I have a Harbor Freight little oil-less compressor (probably used for nail guns) and it says it goes to 160 PSI but will NOT fill 80 PSI so if I drag a compressor on a camping trip, it is the Dewalt. The HF compressor cost like $30 on sale and is pretty much useless for most anything.

I carry a DeWalt 20volt compressor, no tank. It'll top off my tires that require 123PSI. It has to rest every 10 minutes, but it'll get there.

[flybouy]

George there's another compressor rateing to watch when compressor buying. Look for the cubic feet/min. rating which is a rating for the volume. Typically they will be rated @80 psi if they are designed to run air tools. The higher the cfm the faster it will inflate a tire.