G rated tires versus E

I just went thru the same situation.  I replaced my E rated tires with G rated tires with Goodyear G617. ( not sure of the difference between G 617 and G 614).
the new ones are rated for about 700 pounds more per axle.  I have a three axle Stacker that weighs a little over 20K.

I considered 17,5 wheels but I have a problem with my height.  The trailer is 13 feet 6 inches already.  They may have low profile tires but I was afraid of the overall height and how it might raise it.

I will report later on any problems with the Goodyears but I hope I solved my issues with tires on the Stacker.

The 215/75/17.5 are .5" smaller diameter compared to the 235/85/16 G614, I've never heard of a G617 are they new.

Denny

They are new to me but I am not a tire expert.  I got them from America's tire in Albuquerque.  Six of them were almost $2,200.

When I was having problems with my second set of 614G tires I talked directly with GY and I was told because of the dynamic loads that trailer put on tires to always run them at max pressure but I still had problems with them.

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Yeah Goodyear had issues with the G614 in the early to late '00s.
I think it was in '08/'09 era Goodyear made some internal changes. We don't see G614 tires issues much anymore. Like all tire makers tell us low pressures = heat.

Goodyear website says this;
      Goodyear Tire and Rubber .... weighing RVs                 
                          Special Considerations

* Unless trying to resolve poor ride quality problems with an RV trailer, it is recommended that trailer tires be inflated to the pressure indicated on the sidewall of the tire. Trailer tires experience significant lateral (side-to-side) loads due to vehicle sway from uneven roads or passing vehicles. Using the inflation pressure engraved on the sidewall will provide optimum load carrying capacity and minimize heat build-up.*

For those that are using the new Carlisle RH (or any Carlisle ST tire).... Carlisle says;

*Under inflation is the number one cause of trailer tire failure. Low inflation pressure elevates tread temperature, especially as speed increases. A tire can lose up to half of its air pressure and not appear to be flat. Check inflation with a quality tire gauge. Operation of atrailer tire that is 30 percent under-inflated can reduce tire lifespan by approximately 55%. An underinflated tire creates abnormal tire flexing and excessive heat causing the following:
? Tire damage and failure.
? Ride and handling disturbance.
? Reduction of tire life.
? Decreased fuel efficiency by as much as 10 percent. Driving on tires with too much air is also not recommended. Over-inflated tires are more likely to cut, puncture or fail by sudden impact.
-Maintain air pressure at the maximum PSI recommended on the tire sidewall.

The Warranty is void if the tire or wheel fails due to damage from improper inflation pressures, exceeding the maximum speed limit, or overloading the tire beyond the maximum load capacity stated on the sidewall*

HueyPilotVN said:

They are new to me but I am not a tire expert.  I got them from America's tire in Albuquerque.  Six of them were almost $2,200.

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I did a little Google searching and the only G617 I can up with are the ones on your other thread, by looking at the tread pattern and weight rating you gave they are the same as the G614.

Denny

Gary everyone should know the GVWR of their trailer. That what I'm mathing out the tire pressure from. So if 99.9% all conditions should fit within GVWR of the trailer. Everyone has access to the weight rating on the side wall of the tires, everyone has access to the MAX pressure on the sidewall of the tires. Also 99.9% of all people have a Smart phone with a calculator.

(GVWR / Amount of Tires) / Tire Weight Capacity x Max Pressure = Inflation Pressure

So it nothing about scale weights. It about GVWR... This simplify the entire thing and covers wider range being you figuring for absolute maximum weight of the trailer. Still in all it would be a good idea to scale the trailer and know what you actual weight is vs GVWR of the trailer. Because this will not correct for a over weight trailer nor will it correct for driving faster than the speed rating of the tire.

I simply inflate to cover the max GVWR of the trailer. So for example I've got 2 axles (4 tires) rated for 2980 @ 80 PSI Load Range E. RV is rated for 8,500 pounds.

8,500 / 4 = 2,125 / 2,980 = 0.71 * 80 = 57 PSI (Inflate 60 PSI).

If I inflate to MAX 80 PSI I would be capable of carrying 11,920 pounds of trailer I've only got a mere 8,020 scaled weight and 8,500 GVWR rating...

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I think all that can be said on this subject has been repeated several times now.

I made a mistake about the G 617.  My paperwork says G 617 but the tires are G 614.  Somebody just wrote it wrong on the paperwork.

My fifth wheel came with LT tires. At 80psi they have a speed rating of 105 mph. that leaves a little more room for error than with ST tires @ 65 mph.

namumac1 said:

My fifth wheel came with LT tires. At 80psi they have a speed rating of 105 mph. that leaves a little more room for error than with ST tires @ 65 mph.

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And what is the name brand on your trailer and year of manufacturer?

FastEagle said:

And what is the name brand on your trailer and year of manufacturer?

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Cameo/Carriage 2001

Using Moparman's calculation I am right at the max on my TT. They sure don't build in a lot of room for error at the manufacturer. I have a GVWR of 9798/4=2449.5/2540=.9643*65=62.68  So with that calculation I need to keep tire PSI at 65 which is max.

martin2340 said:

Using Moparman's calculation I am right at the max on my TT. They sure don't build in a lot of room for error at the manufacturer. I have a GVWR of 9798/4=2449.5/2540=.9643*65=62.68  So with that calculation I need to keep tire PSI at 65 which is max.

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I think you would subtract tongue or pin weight from the GVWR before you divide by 4.

I wouldn't subtract pin or hitch weight. Weight is weight.

Flywriter:
You said not all of the failed tires had unusual wear. What do you consider unusual wear ? For example outside or inside rib wearing very quickly. If this is the case you could have bent axles which is very common on those heavy trailers. It happened to me twice with my Montana. I would definitely check that before striking out with expensive G614  Goodyears. They will wear just as fast if your axles are bent and then you would feel even worse.
Just a thought:

I, too, have opted to upgrade my E rated (Goodyear Marathons, ST235R80/16) to the Goodyear G614 (LT235R85/16) as I had 2 of the Marathon tires on my fifth wheel disintegrate within 100 miles of each other, causing extensive damage to the trailer. All of the tires were just over a year old and were properly inflated according to the manufacturers recommendations prior to leaving on a proposed 3 month trip across the country.  All of the tires were in excellent visible condition.  Needless to say, that trip was immediately cancelled.

It appears that the numerous complaints have been filed against the Goodyear Marathons over the past several years.

jackdn0610 said:

I, too, have opted to upgrade my E rated (Goodyear Marathons, ST235R80/16) to the Goodyear G614 (LT235R85/16) as I had 2 of the Marathon tires on my fifth wheel disintegrate within 100 miles of each other, causing extensive damage to the trailer. All of the tires were just over a year old and were properly inflated according to the manufacturers recommendations prior to leaving on a proposed 3 month trip across the country.  All of the tires were in excellent visible condition.  Needless to say, that trip was immediately cancelled.

It appears that the numerous complaints have been filed against the Goodyear Marathons over the past several years.

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Forest River RV trailers (like others from different manufacturers) often times use OEM tires right on the borderline of the fitment regulations. This reference ( http://www.forestriverinc.com/product-details.aspx?LineID=164&Image=5030 ) provides the current specs a Forest River 3450RL. I?m just going to do the math for you. Those specs list the GVWR for the 3450RL as 16014#. From that I?m going to deduct the published hitch weight of 2334# (a mandatory figure the trailer manufacturer must provide). The result is 13680#, divided by 2 = 6840#, that?s the GAWR for each of two axles. It must also be the GAWR for each of those axles described on the trailer?s certification label. Divided by 2 = 3420#, hmmm, that?s the maximum load capacity for the GY ST235/80R16E tires. An overloaded axle or single overloaded tire position will cause rapid degradation of the Original Equipment tires. The 3450RL does not have a very generous cargo capacity and could very easily cause your early tire problem when loaded for a long trip.

In any event, you need to make a trip to the scales and then get some tires with more load capacity (as you have already indicated you're going to do).

I had 2 of the Marathon tires on my fifth wheel disintegrate within 100 miles of each other

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Again that tells me your doing something wrong.

Over inflation
Over speed
Over weight
... or combination of the above.

Tires don't magically just disintegrate and within 100 miles of each other... That for sure tells me something is wrong.

Mopar1973Man said:

I wouldn't subtract pin or hitch weight. Weight is weight.

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Why would you count the weight as being on the trailer tires if it is on the truck.  I would think if you had a 10k 5th wheel with 2k on the pin you would then only have 8k on the trailer tires.  So that would leave 2k on each tire if balanced perfect with 2k on the truck.

Please correct me if I am wrong.  I don't want to be telling friends incorrect info.

I'm with you, Elkhound. It's only the axle weight that actually loads the tires.  However, if you do NOT deduct the pin weight, then you will have enough extra capacity at the axle for those times when the weight is shifted more toward the axles than the hitch. This can happen in going over a gully or RR track where the trailer pitches fore & aft, or a steep up hill grade, or maybe an accidental overload. Some extra tire capacity is a good thing (at least within reason).