Tire pressure

[Maclin]

Re: Tire pressure

Seems like a tire-to-load requirement mismatch to me, with the combo of tires or trailer or wheels meant for a much higher load.

 

[WIMUSKY]

Re: Tire pressure

I think we scared away the OP because he hasn't been active since posting the question.....

 

[san dimas]

Re: Tire pressure

I'm still here. Just enjoying the conversation. Looks like a 50-50 deal. I've been running 60 psi without any problem, although the trailer does bounce a bit. Keep debating, I'm enjoying it.:happy:

 

[Home Cookin']

Re: Tire pressure

IIRC the stamp on the tire says "MAX PSI XXX AT YYYY WEIGHT" suggesting that you can drop the PSI if you drop the weight--and for that you consult the charts. It's not worth the time or brain cramps to constantly adjust for changing loads (consider, car or large boat, the weight differential alone of a full v/ empty gas tank (30 gallons on car; 80 on boat), or passengers for a car.) But for a BMT of relatively constant weight far below the max weight capacity of the tire it only makes sense to adjust for it. Just as you might adjust for temps (also mentioned on the stamp).

Hope you slide rule guys don't mind a little common sense thrown in.

 

[Silvertip]

Re: Tire pressure

The only way to determine which side of this fence you want to be on is to use an IR temp gun to measure tire temps after identical runs at both pressure settings. I'm betting the lower pressure results in the higher temp. You also need to know what the load capacity of the tire is at 50% of their rated pressure. Don't forget the weight of the trailer and everything you put in the boat.

 

[bigdee]

Re: Tire pressure

But for a BMT of relatively constant weight far below the max weight capacity of the tire it only makes sense to adjust for it. Just as you might adjust for temps (also mentioned on the stamp).

Hope you slide rule guys don't mind a little common sense thrown in.

Why,why,why??? would anyone want to do this. So far no one has given a logical answer that holds water. The tire manufactures do not want sidewall flex...plain and simple. Give a good explanation of why to lower pressure and I will go away. Trailer tires are not the same as your ordinary tire. Ordinary tires are designed for flex and allow for pressure to be tuned to the load. If you are lowering pressure to reduce bouncing (ineffective anyway) your flexing the tire. Install shocks if your objective is to take the bounce out.

 

[san dimas]

Re: Tire pressure

Every time I stop at a rest stop or for gas, I feel the hubs and tires. So far, just warm to the touch.

 

[UncleWillie]

Re: Tire pressure

... I've been running 60 psi without any problem...

Every time I stop at a rest stop or for gas, I feel the hubs and tires. So far, just warm to the touch.

Exactly how it should be.
Keep up the good work! :joyous:

 

[WIMUSKY]

Re: Tire pressure

I'm with unclewillie.........:joyous:

From the link I provided a while ago:

Inflation
Check inflation prior to going on the road when the tires are cold. The tire pressure measured in pounds per square inch (psi) will increase as the tire heats up when used. BoatUS Trailer Assist service providers say tires are the main reason they?re called to help members experiencing trouble on the road. Under inflation is the cause of most tire trouble because temperatures increase when the tire pressure is too low. So, check inflation prior to going on the road. It?s marked on your tire. Remember, boat trailer tires typically need to be inflated to higher psi than tow vehicle tires. And be sure to also check the psi of the spare tire.

 

[beardeddone]

Re: Tire pressure

The only way to determine which side of this fence you want to be on is to use an IR temp gun to measure tire temps after identical runs at both pressure settings. I'm betting the lower pressure results in the higher temp. You also need to know what the load capacity of the tire is at 50% of their rated pressure. Don't forget the weight of the trailer and everything you put in the boat.

As an ex Truck driver I can say that most of the tires I was exposed to all were rated and filled to 90lbs of air pressure no matter what load I carried whether it was steer drive or trailer tire, it was the most scary part of being a truck driver for me, has anyone ever seen the damage a truck tire can do if it was to explode, I have and that is not a pretty site, I had a drive tire explode on me while driving once and it lifted my cab a good foot when it popped and literately ripped the mud flap off of the truck, when it happened I looked in the mirrors and all I could see was rubber spewing out from under the trailer on both side, two other vehicles blew tires from the debris from my tire blowing, for me weight has nothing to do with rated tire pressure..

Here is the truck I was driving when this tire blew

 

[emilsr]

Re: Tire pressure

Include me in the "keep 'em full of air" camp. Have never seen a properly inflated tire fail, but I've seen LOTS of them fail when run at a smoother riding, lower pressure.

Isn't underinflation for a cushy ride to blame for the Explorer/Firestone problem a few years ago?

 

[fishrdan]

Re: Tire pressure

Here's some fuel for the fire.... :joyous:

MAXIMUM PSI?
As indicated earlier, maximum load range is attained only when the tire is at its maximum air pressure. Yet, should you maintain maximum pressure even if you are towing below the load range of the tires?

Tire manufacturers differ on this point. "You should maintain the maximum pressure at all times," says Carlisle's Garbarino. "There is no advantage to taking air out of the tire. With maximum pressure, the tire will perform and wear better, and you will get better mileage. Reduce the psi, and you compromise the functionality of the tire."

Titan Tire's Evans feels differently. "If you want a little softer ride, drop the psi a bit," he says. However, he cautions that: "They have to know the actual load."

"Trailer owners should set the pressure according to the load," says Goodyear's Fry, who provided the tire pressure vs. load chart that accompanies this story. "Yet, this is not easy to do without weighing the trailer."


Trailer Tire Load Limits (in lbs.) at Various Inflation Pressures
PSI ----------35-------50-------65-------80
ST115/80/13 880 (B) 1100 (C)
ST165/80/13 990 (B) 1230 (C)
ST175/80/13 1100 (B) 1360 (C)
ST185/80/13 1200 (B) 1480 (C)
ST195/80/14 1320 (B) 1610 (C)
ST205/80/14 1430 (B) 1760 (C) 2040 (D)
ST215/80/14 1520 (B) 1870 (C)
ST205/75/15 1480 (B) 1820 (C) 2150 (D)
ST225/75/15 1760 (B) 2150 (C) 2540 (D) 2840 (E)
ST215/80/16 1820 (B) 2200 (C) 2600 (D) 2910 (E)
ST235/80/16 2090 (B) 2600 (C) 3000 (D) 3420 (E)


I do agree that MOST of the time trailer tires need to be kept at max pressure, but not always.

 

[san dimas]

Re: Tire pressure

When I was a kid (along time ago), I worked in a tire shop. Did a lot of split rims and always inflated them in a tire cage. scary stuff.

 

[chris.j.marshall]

Re: Tire pressure

I'm going to take a different approach: fill the boat with water until your rig approaches the load rating of your tires and fill the tires to max psi. This work for everybody?

 

[maproy99]

Re: Tire pressure

I'm going to take a different approach: fill the boat with water until your rig approaches the load rating of your tires and fill the tires to max psi. This work for everybody?

Sounds good to me! Just remember to remove the plug before launching. :joyous:

 

[JimS123]

Re: Tire pressure

that is not a pretty site, ...I when it happened I looked in the mirrors and all I could see was rubber spewing out from under the trailer on both side, two other vehicles blew tires from the debris from my tire blowing, for me weight has nothing to do with rated tire pressure..

View attachment 175905

What does it have to do with then?

I have had 2 tire issues in my 45 years of towing trailers on the interstate. Neither was due to my lack of maintenance or improper pressure on MY equipment. Both were due to some GD truck driver who had one of his recap tires blow up right in front of me.

So, did you stop and offer to pay for the damage to the other unsuspecting drivers who, through no fault of their own, had their property damaged? In my case the ahole just kept on going.

Sorry, but this just hit a nerve with me. I've just met too many irresponsible truck drivers.

 

[oregoncruiser]

Re: Tire pressure

Ohhhhh... this is getting good now!! Keep it going, I'm sure consensus is one post away!!

 

[beardeddone]

Re: Tire pressure

What does it have to do with then?

Meaning tire pressure doesn't necessarily be low to just blow

I have had 2 tire issues in my 45 years of towing trailers on the interstate. Neither was due to my lack of maintenance or improper pressure on MY equipment. Both were due to some GD truck driver who had one of his recap tires blow up right in front of me.

All I can say is sometimes ***** happens

So, did you stop and offer to pay for the damage to the other unsuspecting drivers who, through no fault of their own, had their property damaged? In my case the ahole just kept on going.

Oh yes, my company had the insurance even the police was there a real jerk wouldn't even help a lady change her tire and I told the cop he was an ***** hole after I helped her change it.

Sorry, but this just hit a nerve with me. I've just met too many irresponsible truck drivers.

No offense taken by me, but I have learned one thing, some of the worse drivers on the road besides 4 wheelers are truck drivers.

Have a good one

 

[roscoe]

Re: Tire pressure

I only drove a big rig for a few years, and my biggest fear was blowing a steer tire.
They can blow the whole front end apart.

 

[Hoobz]

Re: Tire pressure

By reducing the pressure of the tires on a lightly loaded trailer to 35 from 65 you have instantly massively reduced road surface causing vibrations to the trailer, it's components and the boat itself and everything in it.

But, hey, some of you are too insulated in your 5 tonne US pick ups to notice it. No road surface vibes being transmitted through the hitch to your vehicle.

In the mean time the over pressurised tires are needlessly causing your trailer wheel bearings to cop zillions of needless jack hammer type hits from over inflated tires running along often rough road surfaces, as well as it's lights and other components, also everything in your boat is vibrating more than it needs to be, at varying frequencies depending on the road surface, just because you insist on sticking to the maximum pressures.

Sure you may save a tiny bit on juice, and maybe the tyres may just last a few miles more, but in the meantime you could be wondering why things keep falling off everywhere. Actually, like was posted earlier on, you'll have uneven tire wear in the centre of your tires anyway with over inflated tires so I take back the notion that your tires may last longer being over inflated for a load.

Ofcourse, it's better to have too much pressure than too little, and if you can't work out a reasonable compromise you should stick to the maximum. If you are a bit more savvy and smart about tech stuff then adjust according to your load. It's not hard.

An over inflated tire also tends to skip over the top of rough road surfaces. Ask yourself how well a tire can be gripping the road surface if it's over inflated and skipping over a rough surface. Not very well. A softer tyre absorbs many more imperfections in the road surface and maintains contact AND GRIP. But again if you can't see this side of the debate then you certainly shouldn't be adjusting your tire pressures to the load. It will be too risky for you. Stick to the maximum please. For your own sake.


Meh.

Keep riding your trailer around on circular stone if you want. Go for it.



Just remember we are talking about light loads. The other reason heavy loads need higher pressure is to help stop the trailer from swaying. Higher pressure gives the tire more rigidity. Higher tire pressures are the easiest way to nip trailer sway in the budd.