Truck & trailer tire pressure recommendations

[SHyans]

Hey all you towing specialists.

There is a 3rd gen thread in No Engine Trans talking about tire pressure and that got me thinking.

I have a 10,000 lb. empty dual axle 21 foot trailer that recommends tire pressure of 50 psi. I have BFG T/A 315's also recommending 50 psi.

In the other thread guys are putting up to 65-70 psi in the truck tires with typically 5-15lbs higher pressure in the fronts.

While towing this trailer what should I be putting in the trailer and what in the truck. The trailer loaded may only be about 500lbs more with water and minimal gear.

Last summer we got two flats in one trip on the trailer and I am wondering if tire pressure may have contributed. We do travel quite a bit on fire roads and could have picked up some shrapnel but... . This is our second year with this trailer after having a pop up trailer with a Tundra as the tow vehicle.

Bought the Ram when the Tundra struggled towing the new trailer.

Poor me!

Thanks for your input.

Steve

 

[B.G. Smith]

I always inflate the trailer tires to the maximum recommended on the tire sidewall, on the truck I use the chart that came with the original Michelin tires on the truck, 70lb. front loaded, 65lb. rear. If I am going on a trip without the trailer, I let the rears down to 45lb. and 65lb. on the front. bg

 

[champspa]

I pull a 5k unloaded and 14k loaded gooseneck and with e rated tires run 80psi in the tires if the tires get low I will have a flat , been there know that, hope it helps.

 

[rluft]

There are alot of opinions on this, I will share mine. Never exceed the cold tire pressure that is molded into the sidewall. The recommendations on the door are for the stock tires and for replacements of the same size and service description, these are probably too much for empty and perhaps not enough for full load.



What I do is go to a truck scale and get some weights. I have the empty weight and the weight of the truck and trailer as I will travel with it. Then I went to the mfg's website and found the load/inflation recommendations. Now I know that that when I have 5100 pounds (the weight with my 5ver hitched) on the rear axle I need 59 psi to safely hold the weight. When empty I only need 45. The only time I will put the 80 psi max that my tires are reated is when I know I have a big big load but don't know how big. I usually add 3-5 pounds over the recommended just to be on safe side.



I just got new tires. The old ones had 55,000 miles and had worn consistently across the tread, not bad in my mind.

 

[klenger]

Based on the chart on the last page at http://www.klenger.net/dodge/3rd-gen-reference/2004-tire-inflation-pressures.pdf, I use 65# all the way around empty or towing.



Keeping the same pressure all the way around is easier when I take the truck into Discount Tire as the techs there don't seem to be able to read.



I tow just often enough that's it's too much of a PITA to change pressure from empty to towing.



I made a tape with a label maker and put the tire pressure, lug nut size, and lug torque inside the fender of each tire.

 

[SHyans]

Good info... . thanks!

I need to get weighed so I have more exact specs to work with.

 

[LesStallings]

Based on the chart on the last page at http://www.klenger.net/dodge/3rd-gen-reference/2004-tire-inflation-pressures.pdf, I use 65# all the way around empty or towing.



Keeping the same pressure all the way around is easier when I take the truck into Discount Tire as the techs there don't seem to be able to read.



I tow just often enough that's it's too much of a PITA to change pressure from empty to towing.



I made a tape with a label maker and put the tire pressure, lug nut size, and lug torque inside the fender of each tire.

Do be sure to note the instructions on page 1 that says to add 10# to the recommendations for sustained speeds over 65mph.



I tow at highway speeds for 10 continuous hours (two short stops) and therefore I will go with the added 10# in the truck tires. For my rig, this ends up with 70# in the front and 75# rear.



Trailer tires are ALWAYS run at max pressure. Sidewall flex is the death of many trailer tires.



Another thing to note is the trailer axle manufacturers recommendation to torque trailer wheels. New or after changing tire/wheel, the recommendation is to retorque after a short distance. I've found that the wheels ABSOLUTELY need to be retorqued. Even after they have been mounted for a long time, I always torque them each morning before I leave for a 10 hour run. It surprises me how often one wheel will take another ¼ turn or so. I bought an inexpensive ½" torque wrench at Walmart and a 13/16" deep socket and extension at Sears. I keep them behind the seat.



Be safe. Take the time to check.

 

[SHyans]

I bought a cheap-o torque wrench and check them frequently. All were quite loose after sitting for the winter.