New tire pressure ?

[Robbie R.]

I was told recently that the 50 PSI ratings for GY marathons was not enough according to AS and that a new pressure was set at 65 PSI, anyone else hear this ?

Robbie R.

[jcanavera]

Depends on the rating of the tire. D rated Marathons have a max cold inflation level of 65 psi as stamped on the side wall. You also, dependent upon year of your Airstream, have a label listing inflation pressures that Airstream mounts on the body of the trailer. My recommended inflation based on the tag is 65 psi. GY has a chart on their site that lists load capacity and tire pressure required to carry specific loads. Bottom line under inflation is a tire killer.

Jack

[reddogfox]

Robbie R
Please note that some Goodyear Marathon tires are made in both “C” and “D” rating in the same tire size. My trailer uses “D” rated ST225-75R15. When I recently replaced them I double checked the replacements to make sure they were not “C” rated tires. “C” rated tires have a maximum PSI of only 50 pounds.

[silverback]

Our tires are rated at 65 PSI cold. The Airstream sticker also specifies 65 PSI. I run ours cold at 62 PSI. Mostly because in AZ they will get much higher PSI in the summer heat and I find that is a bit too harsh a ride for the trailer. I'll probably add a pound in the colder seasons.
-Ken

[SilverRanger]

Originally Posted by jcanavera

... My recommended inflation based on the tag is 65 psi. GY has a chart on their site that lists load capacity and tire pressure required to carry specific loads. Bottom line under inflation is a tire killer.
Jack

Yep. That's why I keep them at 65 PSI. So far, no problems.

[53flyingcloud]

It might a good time to re-interrate this previous warning..
Passenger tire's wheel stem for passenger cars only..
Truck tire's wheel stems for truck only..
In all cases, make sure you have the proper tire stem for the load and, the tire's wheel that you are going to be using.
Most passenger car tire stems should never be used on anything but cars. There's a huge differences in the size of the base of the stem as well as the max pressure that you can pump your tires to..
Not to frighten you, just be "safety aware"...
Thanks and, have a safe trip always..
53FC

[Beginner]

I use truck Metal Valve stems in my wheels. Never worried about a problem concerning valve stems. They are only marginally more expensive than the rubber ones.
Beginner

[Cracker]

Airstream switched to "D" rated tires sometime after 2000. My 2000 Excella says 50 psi on the placard. I went to "D" rated tires the last time I changed them but I still maintain the pressure at 50 psi. "C" and "D" rated tires have the exact same capacity at 50 psi but the "D" rated tire permits the additional 15 psi. By scale weight the 50 psi would still appear to be adequate for my trailer. I don't know if Airstream changed the axle rating, or increased the load capacity of the trailer, when they went to the "D" rated tires. I've never had a problem with my current cargo carrying capacity and raising the inflation to 65 psi would do nothing more for me than to make the trailer ride harder. For the record, I'm fanatical about checking tire pressure - maintaining all four tires within 1 psi +/- of 50 psi when cold!

[Aage]

I have a new set of ST tires, load range D, and the max is 65 psi, like most of the ones I see and hear about on here.

So: the MAX on the sidewall is 65 psi, and my trailer has NO placard (maybe they didn't placard them back in '74?) so here's the question:

What pressure should I run them at?

Henri the Sovereign is 5,000 lbs dry, so add another 2,000 lbs of My Stuff, including the half-full fresh water tank, and he's ready to leave on the Run For The Sun, weighing in at 7,000 lbs approx.

I see folks running at the max in theirs, others saying 50 psi, and my tire seller telling me 35-40 psi. Is anyone right? Are they ALL right?

Please give me your suggestions, oh, great group of all-knowing and all-seeing Airstreamers...

[Minnie's Mate]

I see folks running at the max in theirs, others saying 50 psi, and my tire seller telling me 35-40 psi. Is anyone right? Are they ALL right?

All I can tell you is that my Airstream build date was 01/06 and the tire code on all four tires says that all four tires were made 11/05. I have between 28,000 and 30,000 miles on this set of tires. I run 65 PSI in each and spray 33 spray (UV Protectant for rubber, and others). I also put a lot of Interstate driving at Interstate speeds; all other roads I stick to the posted limit, too. I had my first flat two weekends ago at approximately 60 MPH and was notified by another motorist in time to prevent damage to the Airstream.

That's my experience and driving habits.

[ROBERTSUNRUS]

Hi, Airstream recommends 65 lbs on my trailer as is marked on the sidewall of my tires and that is what I put in them. On my last trip, same as any other trip, I do all my wheel torqueing and tire pressure settings at home before we hit the road. On my last trip we went over 3,800 miles in temps rangeing from zero to 98 degrees and in altitudes from sea level to over 10,000 feet in 15 days. During this and every other trip, I do a walk around at all rest stops and gas stops giving my tires and hitch a visual inspection and kick my tires to make sure they are still firm. I do not check them with a tire guage or make adjustments on the road.

[2dabeach]

Originally Posted by Robbie R.

I was told recently that the 50 PSI ratings for GY marathons was not enough according to AS and that a new pressure was set at 65 PSI, anyone else hear this ?

Robbie R.

Robbie R....Our 2007 25' with ST 225/75 R15 tires are rated at 65 psi. Attached is an inflation guide that is available on the Goodyear site. My tire at 50 psi is rated at 2,150 lbs capacity, at 65 psi the capacity increases to 2,540 lbs.

[CrawfordGene]

Originally Posted by Aage

I see folks running at the max in theirs, others saying 50 psi, and my tire seller telling me 35-40 psi. Is anyone right? Are they ALL right?

Please give me your suggestions, oh, great group of all-knowing and all-seeing Airstreamers...

And you will get them, Aage.

The prevailing wisdom (no comment as to whether it is "wisdom") is to inflate tires as Airstream recommends. But does Airstream know what it's talking about, or is it just taking the safe, lawyerlike approach, and saying the maximum is right?

So what does a much bigger company, one with much more money for lawyers and tire engineers say about their products? Toyota recommends 32, F and R, for my LR C 4Runner tires. They recommend 32 F and 35 R for my Tundra LR C tires. What's the difference?—the Tundra is heavier. The tire will hold 45 or 50 lbs.—not sure which. After all its about 3 am and somebody started a motorcycle a little while ago, woke me up, and I'm bleary eyed.

When I was at the Airstream service center and had LR E tires installed I discussed tire pressure. I was told 85 lbs, the maximum the tire will hold was what Airstream recommended. I had asked Michelin and they told me 75. Toyota might say less if asked about trailers based on the pressures they recommended for their trucks.

If I operate on the bigger means more money, thus more lawyers and tire engineers, theory, Toyota wins. But does Toyota employ tire engineers? Michelin surely does. Does Airstream?

Just to complicate matters, LT tires and ST tires have different weight capacity for the same Load Range.

Using a tortured intellectual process I will call "educated guessing" (and you may quarrel with the adjective "educated") I decided weight does matter and told the tech to put 70 lbs. in my LR E trailer tires.

Ah, but another thought. Tire pressure gauges disagree. I told the tech to put 70 lbs. in and when I measured the pressure using my handy $10 gauge, it was 68. Then I used the TPMS system and it said 67 (usually there's a 3 lb. difference, not 1 lb., between them, but I choose to ignore that discrepancy). The Airstream gauge said 70. Since it was ready to rain, I decided not to add 2 or 3 lbs., especially since the gauge on my little compressor disagrees with the other two. Thst's how I ended up with 68 or 67 instead of 70. 70 seems to be about right for LR E in a LT tire for the weight of the trailer plus some extra. Following that theory, LR D ST tires should have less than 65. All I have to do is drive a few miles, and it would say 70.

Of course, there's "cold pressure". Temps can vary a lot during a day, especially the further you are from the coast. People say to check pressure during the coldest part of the day, a time which may be very early in June, long before you get up. A tire in Key West may increase 5 pounds during the day, 15 or more in Arizona. Overpressure will mean a harder ride, so maybe cold pressure means "whenever I start driving compensating for which side of the trailer is in the sun".

I'm going back to bed. The motorcycle is gone. I hope I've clarified things.

Gene

[Ahab]

Originally Posted by SilverRanger

Yep. That's why I keep them at 65 PSI. So far, no problems.

Same here.