Trailer tire -

[nofearengineer]

The Marathons are good to 65 mph, and they do indeed say to put an extra 10 psi in them if you want to run up to 75.

The reason for more air is:

The tire sidewall bulges out slightly at the bottom when your boat and trailer are sitting on it. Duh.

As the tire rolls, the the sidewall is flexed over and over again, as each spot on it passes through the bulge area. This is what generates heat. It's like bending a piece of stiff wire repeatedly until it gets very hot. That's why I always get out and check the temps with my hand. Regardless of what any piece of paper tells you, if the sidewalls are hot, you're doing something wrong.

Adding the extra air reduces the bulge somewhat, reducing the heating.

The Marathons are supposed to inflated to 35 psi hot (up to 45), but I have heard of guys running them at 65 psi. Just begging for a catastrophic blowout.

[Embrey]

maybe some of you dont have enough ply tires that can handle enough load and air pressure. mine are 50 psi tires,which should be a minimum on a bass boat. my skid loader trailer tires are 100 psi 12 ply..lol

[nofearengineer]

Embrey, the psi of your tire varies with the weight of your trailer. For instance, I inflate mine to 35 psi because that is what it should be inflated to at a weight of 3,000 lbs.

Over-inflating your tires doesn't accomplish anything but uneven tread wear.

I will direct you to this chart.

http://www.goodyear.com/rv/pdf/rv_inflation.pdf

[Embrey]

none of my tires are overinflated...not all tires have the same psi capabilities...and yes it wouldnt make sense to inflate my tires that will handle 100 psi all the way to haul around a lawnmower. but i haul around 10,000 lbs on it.

[FlatBottom_16]

After looking at the OPs failed tire pictures it would be very difficult to determine the cause without having the tire in hand for closer investigation.

The H188ST is a common trailer tire found at such places as Sam's Club. The OPs are bias tires rated at 1760# at 50 psi. The life expectancy for such tires is 5,000 - 12,000 miles or 3 - 5 years. Almost all manufacturers of those tires require them to be aired to full sidewall pressures at all times. Some manufacturers such as Carlisle will not honor warranty claims if they suspect the tires have not been kept at full sidewall pressures. While I'm on the Carlisle ST line of tires I'm compelled to warn all owners of them that their warranty period is among the shortest in the ST industry - two years from date of purchase.

ST tires cannot be manipulated to extend their recommended speed limitation of 65 MPH. That procedure is only authorized for truck tires.



p.s. If a closer inspection of the failed tire reveals melted cords it's an indication that the tire overheated, lost its air and failed. Speeding above 65 mph with less than the recommended tire pressures will cause such a condition. Bottom line - keep your trailer tires aired to the trailer manufacturers recommended pressures - found on a tire placard - or full sidewall pressures.

FB16

[Top Tiger]

Something else to think about. I noticed that my tires (Carlisle 6 ply) were wearing out faster than normal not quite as bad as the one pictured, though. Took it to the local trailer shop and the fellow there told me that the axle is supposed to have a slight upward bow to it. Mine doesn't. Not noticeable unless you really look for it. It's still a bent axle and has to be fixed.