Tire pressure

WIMUSKY

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Mine are STs.

Funny, we're having this same conversation on a RV forum...
 

randale

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12 year old tires....pffffft.

My son had a 3 year old boat with OEM tires. Not cheepies from WalMart, but what the trailer manufacturer used (OK, cheep tires). He had a blowup on the interstate right in front of me and when we inspected the other tire is was a mile away from disaster as well. Both were properly inflated.

Then, I inspected my 25 year old tires (Goodyear USA made) and they still looked like new (local driving, fresh water, garage kept).

I firmly believe that tires have gone to crap in the last X years. So, maybe if you have some oldies with low mileage and not a lot of sun exposure, it might be best to hang on to them.

The rest of the story is that my 25 year old tires were not STs. They were P series OEM Trailer manufacturer car tires on a tandem trailer with a capacity that meet the requirements.

After these and other experiences, I won't buy an ST unless there isn't a P or LT that has the needed weight capacity.

Reminds me of the old Continental tires on uncle's Caravan.We visited them a couple of months ago for a family gathering and helped him install the rack and tonneau cover on his truck. The Caravan is their Sunday ride and till have the OE tires for about 8 years now.
 

82rude

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Come on guys give the poor tires a break.All this pressure is too much .One of them is gonna blow a gasket!P.S tread carefully.
 

roscoe

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I don't use no stinking air.
I fill my tires with sand.
They never flex.
Hasn't happened yet, but I hope there is a video camera recording when one of them plows out.
Maybe I should use colored sand so it shows up better in the video.
 

JimS123

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Reminds me of the old Continental tires on uncle's Caravan.We visited them a couple of months ago for a family gathering and helped him install the rack and tonneau cover on his truck. The Caravan is their Sunday ride and till have the OE tires for about 8 years now.

Car tires are whole other ballgame. STs say on the sidewall "not for use if people are in the vehicle". OTOH car tires don't say "not for use on a trailer".
 

Texasmark

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My take on over inflating results in tire wear in the center of the tire. Tires are made to run with the tread flush with the pavement.....besides the wear and tear on your suspension and the boat itself. I'll keep my adjusted to the load.
 

WIMUSKY

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That's why everyone should pay attention to their tire wear and adjust accordingly...
 

bigdee

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My take on over inflating results in tire wear in the center of the tire. Tires are made to run with the tread flush with the pavement.....besides the wear and tear on your suspension and the boat itself. I'll keep my adjusted to the load.

True for passenger tires,not ST tires. If you want to adjust air pressure for the load you should use LT tires on your trailer.
Apart from the fact that correct inflation pressure will yield the best fuel economy, ride, tracking and longevity, it will also help prevent damage that can cause sudden tire failure. When an underinflated tire is run at normal highway speeds, the excessive sidewall and tread flex create heat that can damage the inner liner, casing and outer sidewall of the tire.
According to guidelines published by the Rubber Manufacturer’s Association (RMA), any tire
that has been run at less than 80 percent of recommended air pressure for the load it is
carrying should be inspected for possible damage.
 

bruceb58

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According to guidelines published by the Rubber Manufacturer’s Association (RMA), any tire
that has been run at less than 80 percent of recommended air pressure for the load it is
carrying should be inspected for possible damage.
Yes...recommended air pressure...not MAX air pressure.

The manufacturers that build the tires have inflation charts for a reason unless. Of course there will always be a person ^^^ who thinks they know more than the manufacturer.

These tire pressure threads show how many either can't read or comprehend what is written on the sidewall of a tire and/or on the inflation charts/stickers or they just ignore thinking they know more than the people engineering the tires.


RV Tire Safety: Inflation

Example 2: There was a change in tire size AND in Load Range as can happen with the new Goodyear Endurance.
Original tires were ST205/75R15 LR-C and you mistakenly bought ST225/75R15 LR-E
Back to the Load & Inflation table for ST type tires we see that the ST205 is rated to support 1,820# @ 50 psi and the ST225 can now support 2,830# @ 80 psi. This is a 55% increase in load capacity. If the owner were to run the 80 psi as indicated by the tire sidewall the "ride" would probably be hard on the TT. In this case I would not follow the inflation on the tire sidewall. I would suggest that in this case the owner continue to run 50 to 55 psi and enjoy better tire life. In this example the owner expressed concern about running lower inflation than marked on the tire. Some people even incorrectly said that running less than 80 psi would somehow overheat the tire. I pointed out that I saw no problem with running less than the sidewall inflation as long as the actual load had been confirmed with actual scale readings and that there was a good margin of capacity over the actual loading.

I have some Load range E 15" tires on my Wellcraft trailer. I wanted to find Ds but they were unavailable. I wanted Ds for some extra margin from Cs as even the Cs were fine. Per the inflation charts I air them up to 65 PSI which gives me way over 20% weight margin. Airing them up to the side wall pressure of 80PSI would just be stupid! The tire would be riding down the road on the center of the tread.
 
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Scott Danforth

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:popcorn:.... this is almost as good as an oil thread......
 

roscoe

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These tire pressure threads show how many either can't read or comprehend what is written on the sidewall of a tire and/or on the inflation charts/stickers or they just ignore thinking they know more than the people engineering the tires.



Well, the manufacturer's big yellow stickers that were on the last 2 sets of trailer tires that I bought, said to run at 65 psi at all times.
65 psi is also the max air pressure on the sidewall.
Receipt also included a warning/disclaimer, that said to run at max sidewall pressure.

There is also a world of difference in what radial trailer tires will tolerate, vs. bias plies.
 

bigdee

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I guess the drivers of 18 wheelers stay busy adjusting air pressures when trailer is emptied!
 

bruceb58

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JimS123

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:popcorn:.... this is almost as good as an oil thread......

That's silly. Everybody knows that Amsoil is the best and wallyworld Pennzoil is the worst. Er, sorry I got sidetracked.

I have an idea. Why don't all the people that ever had a catastrophic tire failure post what their load and pressure was so we can decipher the root cause of the problem.
 

bruceb58

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I have an idea. Why don't all the people that ever had a catastrophic tire failure post what their load and pressure was so we can decipher the root cause of the problem.
Problem is, they won't even know. One reason I use a TPMS on my trailer tires.

Of course, you also need to ask age of the tires. If they are over 5 or 6 years old, they are on borrowed time.
 

Scott Danforth

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catastrophic boat trailer tire failures

tire #1 - a 6" section of re-bar going thru construction on 465

tire #2 - a 5" sidewall gash because I found a broken cast-iron pipe with the trailer


non-catastrophic boat trailer tires failures:

tire #1 - bulge appears in side wall due to tread separation. tire was 10 years past its use-by date (about 18 year old tire)

tire #2 - about 50% over-loaded, tire on passenger side starts to shred

tire #3 - 1.2 miles from home, treads start to separate - tire was about 8 years past its use-by date (about a 16 year old tire)

tire #4 - 600 miles north of Florida, noticed treads starting to separate at 85mph as I went around a group of semi trucks..... pulled over prior to all treads leaving carcass, swapped tire, back on road in 10 minutes....had to pass group of semi trucks about 15 minutes later.

I keep my tires inflated about 5 psi less than max. I also use my IR temp gun to read the edges and middle of the tire. as long as all 3 readings are within a degree or two, the pressure is good.

if I change load range, it takes about 3 trips to get the tire pressure dialed in
 

roscoe

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Dad and I have a combined 80+ years of towing.
All on bias ply tires.
All run at max pressure.
Often on 5-8 year old tires.
Only one failure, caused by a nail, which we suspect lowered the air pressure, tire popped off the rim when we hit a set of rough railroad tracks.

This is boring, lets talk about connecting wires together.

Crimp, twist, solder, tape, shrink-wrap, double shrink, adhesive lined shrink connectors.
 

Grub54891

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