Trailer Tire Pressure

[Crestliner2008]

To what pressure do you fill your tires to? I'm getting ready to trailer a small 12' boat and checked the tires with a gauge. It read 15 psi! Quite low for a tire rated for 60 psi. So, I went to the station and paid $1.50 for air (a pet pieve of mine), but the machine would only allow me to put in 32 psi. I'm assuming that for such a small boat, this would be fine, but I'd like to know your opinions. Thanks!

[MN Fisher]

You can get 12v inflators at O'Reilly's for under $20. Will handle the car, bike, trailer. Mine handles up to 120psi.

[sully420]

32psi should be fine for you. I pull a 16" tracker and my trailer tires only need 35psi max

[slonezp]

Max psi on the sidewall

[Glenn]

^^ Agreed ^^  but...

 

Before you go heading down the road, how old are the tires?  If you don't know, or don't know why you need to know, then watch this:

 

 

[Dwight Hottle]

1 hour ago, slonezp said:

Max psi on the sidewall

X2

 

Disclaimer. I was in the tire business for 18 years.

All trailer tires should be inflated to the maximum reading on the sidewall. Fill them when the tire is cold first thing before you run them any distance. Heat build up is what causes tires to fail. Maximum air pressure limits the tire from excessive flexing & keeps them running the coolest. Also maximum load capacity is always achieved at max pressure. 

 

Crestliner you want 60lbs psi for your tires.  

 

Glenn is right tires do have a shelf life and old tires with acceptable tread depth can still be dangerous. 

[Fishing Rhino]

I have read that if you are going to exceed the maximum speed limit of the tires you can inflate the tires to 5 psi over the max pressure.  I did that for five years without a problem, until........ I felt a vibration when I got above 50 mph. 

 

I stopped and looked at the tires and nothing seemed askew, so I continued driving and the vibration got worse.  Pulled into a rest area, jacked each tire free of the ground, rotated each and found one to be seriously out of round and distorted.  Broken belt in one of the tires.  Changed the tire and off I went.  Finished the long trip, got home without further problem.  Went fishing around here a few days later, and on the way home the trailer developed a vibration.  Turned out to be the mate to the first tire that failed on the tandem trailer.

 

Another broken belt.  I drove over 2000 miles on that second tire before the symptom occurred.

 

Lesson learned.  No matter what I may read, I'll never overinflate a tire again.  

[tracker01]

Ok, I have about 1200 lbs. of tin boat sitting on my trailer. My tires state 60 lbs. max. Do I still have to put 60 lbs. in them? I believe at highway speeds my trailer would be doing some serious bouncing around.

[riverbasser]

Google is your friend

 

Boat-trailer tires require a lot of air pressure — in most cases, between 50 and 65 psi. In fact, the correct pressure is almost always the maximum-rated pressure for that tire, which is molded right on the sidewall. Maintaining that pressure is critically important to towing safety.

Tire pressure determines the load the tire can safely carry. The load capacity of the trailer was determined with that specific tire pressure as a factor. If you roll out of the driveway towing your boat with less than the max psi in the trailer tires, you have effectively reduced the load capacity of the entire trailer. Underinflated and thus overloaded tires are the leading cause of trailer-tire failure; the tires overheat and fall apart.

[Dwight Hottle]

16 hours ago, tracker01 said:

Ok, I have about 1200 lbs. of tin boat sitting on my trailer. My tires state 60 lbs. max. Do I still have to put 60 lbs. in them? I believe at highway speeds my trailer would be doing some serious bouncing around.

Yes you need 60 lbs. Under inflating a tire will cause heat build up. Speed kills drivers & heat kills tires. The more you inflate a tire up to the max the less flexing & subsequent heat build up you have. 

[Crestliner2008]

Thanks muchly guys! I knew I was correct and that the air supply machine was either screwed up, or not allowing for over inflation of car tires.

[fishnkamp]

The tire manufacturer would not put 60 psi max on the side of the tire if it should not be inflated to that pressure.

Most likely your trailer uses smaller diameter tires and those need the pressure to support the weight.

[tracker01]

6 hours ago, fishnkamp said:

The tire manufacturer would not put 60 psi max on the side of the tire if it should not be inflated to that pressure.

Most likely your trailer uses smaller diameter tires and those need the pressure to support the weight.

Carlisle’s, 4.8-12

[PECo]

The manufacturer’s tag on my trailer says that I should inflate the tires to 50 PSI, which is the maximum pressure molded into the sidewalks of the tires.

 

HOWEVER, your towing vehicle’s tires are different. They should never be inflated to the maximum pressure molded into the sidewalks of the tires. In recent model vehicles, the manufacturer’s cold tire pressure recommendations should appear on a sticker in the frame of the driver’s side door.

[moguy1973]

I thought the same thing about inflating trailer tires to less than the max like you do with car tires.  Bad mistake.  I had two new tires a put on my 17' Tracker trailer a couple years ago and the tire side wall said 50psi max, so I put about 37-38 in them thinking that would be well enough for them.  Nope, I blew one of them after going over a bump because the lower pressure caused the trailer to bounce too much.  I've put 48-49 since then and haven't had a problem.

[TOXIC]

Also as part of your tire maintenance you need to occasionally coat them with 303 Aerospace Protectant.  Helps with premature dry rotting.  I also cover my tires and fenders since my boat will not fit in my garage.  I go 4 years on a set of tires no matter how much tread is left on them.  I trailer a lot and also keep them at max pressure.  

[WRB]

20 hours ago, Dwight Hottle said:

X2

 

Disclaimer. I was in the tire business for 18 years.

All trailer tires should be inflated to the maximum reading on the sidewall. Fill them when the tire is cold first thing before you run them any distance. Heat build up is what causes tires to fail. Maximum air pressure limits the tire from excessive flexing & keeps them running the coolest. Also maximum load capacity is always achieved at max pressure. 

 

Crestliner you want 60lbs psi for your tires.  

 

Glenn is right tires do have a shelf life and old tires with acceptable tread depth can still be dangerous. 

Reminder it's time to get new tires, tread is good but they are getting old like me!

Tom

[NHBull]

On a side note, check the date the tire was manufactured.  I have seen a few failures to tires that look good, but were older than realized

[RHuff]

I inflated my tires to 50 psi once and they got all kinds of warped on the tred to the point I had to put new ones on. The tire shop said keep at 35 psi. Have always done that sense and gotten good life out of the tires and a much smoother ride when pulling the boat. 

[WCWV]

Tire pressure should be what the tire manufacturer states on the side wall.