Tire Pressure/Rating and CSA...a little more involved

[bubblehead]

After reviewing the CSA in the FDCC forum. I thought it might be useful to let readers aware that I had my tire pressures checked by DOT in Indiana. The following is an excerpt from the regulation;

(h) Tire inflation pressure. (1) No
motor vehicle shall be operated on a
tire which has a cold inflation pressure
less than that specified for the load
being carried.
(2) If the inflation pressure of the tire
has been increased by heat because of
the recent operation of the vehicle, the
cold inflation pressure shall be estimated
by subtracting the inflation
buildup factor shown in Table 1 from
the measured inflation pressure.
TABLE 1—INFLATION PRESSURE MEASUREMENT
CORRECTION FOR HEAT
Average speed of
vehicle
in the previous
hour
Minimum inflation pressure buildup
Tires with 1,814 kg
(4,000 lbs.) maximum
load rating
or less
Tires with over
1,814 kg (4,000
lbs.) load rating
66–88.5 km/hr
(41–55 mph).
34.5 kPa (5 psi) ... 103.4 kPa (15 psi).
[34 FR 9344, June 13, 1969, as amended at 40
FR 44557, Sept. 29, 1975; 41 FR 36657, Aug. 31,
1976; 44 FR 25455, May 1, 1979; 44 FR 47938,
Aug. 16, 1979; 53 FR 18057, May 19, 1988; 53 FR
49401, Dec. 7, 1988; 63 FR 8339, Feb. 18, 1998; 65
FR 70220, Nov. 21, 2000; 66 FR 67694, Dec. 31,
2001; 70 FR 48054, Aug. 15, 2005]

Here's the link: http://edocket.access.gpo.gov/cfr_2005/octqtr/pdf/49cfr393.76.pdf

After checking my pressure (which passed) I showed him the manufacturer's Load Chart which I keep handy and questioned him about the calibration of his guage (which did not have any certification sticker on it) not satisfied with his answer and not willing to make an issue, we discussed some other State regs concerning mud flaps) which vary widley from state to state.

Point being, they are starting to scrutinize and apply the regs more stringently than I have prevously experienced and just the load rating alone may not get you passed.... Your tire pressure may considered also.

 

[Bruno]

Sounds to me that states with no money are going after drivers to get some.

 

[nightcreacher]

Kentucky has what looks like a camera they look thru.It shows the heat of the tire.I was pulled into the scale on I71 coming into the state from Tn.The tire the guy thought was bad,wasn't,but they did find a nail in another tire,they let me go so i could go get it fixed,guess i was lucky,didnt get wrote up

 

[OntarioVanMan]

From the special I watched on Discovery....scales are being outfitted with radiation detectors and heat sensors as well...

 

[ATeam]

I don't know if it is a trend in Indiana or if you happened to get the same nit picker a friend of mine did. He was put out of service for having loose U-bolts that hold the truck body onto the truck frame. The "loose" bolts were detected when the officer used a large pry bar to find them. They were tight when checked by hand.

Rare is the driver who carries the manufacturer's tire data table in the truck with him or her. It is a good idea. The table can be obtained from tire dealers or copied off the internet. Having one like you did may well have saved you a ticket.

Knowing the proper tire inflation pressure for your truck and the loads you typically carry means consulting your tire data table. It does not mean inflating your tires to the p.s.i. number that is printed on the side of the tire.

I learned this lesson the hard way after prematurely wearing out a set of steer tires because they were inflated to the p.s.i. number and not to the number specified in the tire data table. Using the tire data table number increased the tire life of the next set of steers by over 50%.

 

[Crazynuff]

You shouldn't need a regulation to not exceed a tire's rating or to not have a tire inflated to proper pressure . It's just common sense . Lack of maintaing proper pressure is another bit of negligence attornies check out .
Orlando, Florida Truck Accident Lawyer | Over/Under Inflated Tires and Truck Accidents

 

[ATeam]

Yet another example where common sense is not so common.

If you view 100 trucks parked overnight in a truck stop, how many drivers do you see checking their tire pressure in the morning before they begin their driving day? More drivers pee on their tires than check them.

 

[Desperado]

dumb question i keep my tires at 110 psi cold check them after truck sits 4 hrs will i have any problems or do i need to buy some new thingymjib

 

[greg334]

Knowing the proper tire inflation pressure for your truck and the loads you typically carry means consulting your tire data table. It does not mean inflating your tires to the p.s.i. number that is printed on the side of the tire.

Thank you Phil.

I have been told that I need to keep mine at 110 because that is what it says on the side of the tire. The officer said that the outside drivers were both at 97, which they were not. They were a little over 116 because they were warm when checked with my digital gauge - his was off by almost 20 psi. I run them at 105 cold, that seems to give me the best performance and mileage because of the tread.

 

[ATeam]

dumb question i keep my tires at 110 psi cold check them after truck sits 4 hrs will i have any problems or do i need to buy some new thingymjib

There are several tire inflation products and gizmos available to provide solutions to tire inflation challenges. I'm not impressed with any of them. A simple tire gauge and the willingness to use it does the job. Basic tire knowledge is also helpful. A good place to obtain it is tire manufacturer web sites.

Actually inspecting your tires during your pre-trip inspections is also a good practice. Just yesterday I found this item in one of our tires and dug it out before it caused a flat. No tire inflation product will free you from these kind of tire hazards but regular tire inspections will (pre-trip, during-trip, post-trip).

Finds like this and the money they save are why we do pre-trips.

 

[ATeam]

Most truck stops sell an air hose with a truck tire chuck on one end and a glad hand connector on the other. This enables semi truck drivers to use the truck's air compressor to inflate their tires. Glad hands can be installed on straight trucks by most any trailer shop or truck repair facility.

We have one on our straight truck and it makes tire inflation a breeze. It eliminates trying to find an air hose at a truck stop or incurring the ire of the driver behind you if you are using an air hose at a fuel island.

Another time saver is flow-through valve stem caps. You can get these at tire repair shops. They enable you to check your tire pressure and air up your tires without removing and reinstalling traditional valve stem caps.