Trailer Tire Pressure... I know, I know.....

I came to this topic on this site searching with Google for tire-pressure.
I live in Holland and I am no trucker. So wont introduce myself in a seperate topic, because I only answer to tire-pressure related topics.

End 2007 I got hold of the formula that the European tyre makers use to determine advice pressures for cars and later found out that the same is used up to truck tires in Europe.
In America its different , there for truck and LT other formula then passenger and XL/reinforced/Extraload tires . For the last 2 kind of tires the old calculation was realy bad, and in 2006 the American TRA swiched over to the European ETRTO power in the universal formula, but for LT and Truck tires still the old power is used.

What suprises me here is that Police can even give a penalty for to low tire-pressure, because He doesn't know what the pressure should be for the specific Truck.
I think complaint can be made to it, especially because he did not specifie the pressure in his papers. Is it realy already that bad in America.

Needed pressure is all about load on the seperate tire for truck tires.
The pressure written on sidewall or belonging to the Loadrating ( F-load/12PR to H-load/16pr and higher) is not the maximum pressure of the tire.
It is the pressure needed for the maximum load to ride up to maximum speed of tire ( for truck tires) without giving damage to the tire by the about 10 times a second deflecting and flexing back of every segment of the sidewall. Also saw it called the maxloadpressure and in the formula sheet I got it is called the Reference-pressure ( shortened Pr).
The maximum pressure of the tire is , so I concluded of a list of Semperit ( Continental) , wich says that 1,4 times the Pr is allowed to bare 2 times the maximum load, when standing still, that the Pmax=1.4 times the Pr, and then even cold.

I made spreadsheets , the last one for Lighttrucks , but can be used for simple build Trucks ( not to many axles) so if someone wants to know it give the data of Truck and tires and I will calculate.
In Europe on every truck-tire there is a aditional Loadindex written on sidewall with a lower speedrating, and some LT ( C for Comercial) tires also give that.
That means that for that lower speed the tire is allowed more deflection and so a save higher maximum load supported by the tire-maker.
If in America it does not give that , because the tires are of same construction , to laws of nature this system also goes.
But search for it on the sidewall, and be surprised.

If I use sometimes some strange sentences and words , forgive me, English is not my native language.
Greatings from Holland
Peter

 

I can't get any air pump thing to get on my drives. Meaning the angle won't allow proper fit of the hose to put air in. What do I do? Have small hands and still can make it work. I even have trailer hose kit.

 

You have the double-headed chuck and it won't go on the stem?

 

OR https://www.acklandsgrainger.com/AG...Display.do?item_code=MTNS693-12&zone_id=PDPZ2

 

Did the cop even ask what your weight was?

 

Right...only because the hole designs in the rim make it hard to angle the chuck and stem together to pump the air in.

 

US Xpress wants the steers at 110psi, the drives & trailers at 100 psi.

 

105 on the steers
80 on the drives and trailer

AS PER MANUFACTURERS RECOMMENDATION.

I get great life out of my tires and dread the day Buford T. Justice pulls out his pressure gage.

 

Well you were at wrong location at wrong time, no mater what he was looking to find some thing so he can give you ticket. Any way you should have Steer tires 105-110 psi, drive axel and trailer tires should be 100 psi, Cold before you start driving. All tires should be checked once week. This is how I do with my trucks and newer had problem. I don't know if is going to work for you to hire layer for that ticket because you said police officer never mark how much pressure you had in the tires. Good luck .