I just had a flat tire with my 2004 3500 Dodge Ram Diesel Truck. I was keeping my tires at about 80 psi according to what I was reading on the door (it said 85 psi max) and what other people have told me. The AAA service man said I should only have between 40-50 in the tires. I've been told different things by different people. I'd really appreciate advice from this group. It's my only vehicle. I pull a light weight trailer when I go camping. Any advice would be appreciated regarding tire pressure when towing and not towing. Thank you in advance for any information you share.

hobopals
i had a 1999 f250 super duty for 8 years
I ran 60 psi when not towing. When towing I ran
80 psi.

hobopals
Every tire manufacturer has a chart for your tire. Weigh each axle and conform to the air pressure as listed for that weight on the chart. I add 5 psi for insurance.
In my case I run 100psi on the steer, 90 on the drive and 75 on the tag. Notice each is different because on the weight distribution. Other people with the same coach run 110 all around. And then they complain of a harsh ride.
Bill

hobopals,
It also varies with which particular tire you're using. The Firestones my F250 came with were 80 psi tires, but the Bridgestones I used for a while were 65 psi tires. The Michelins currently on her are back to 80 psi tires. Each tire will have at least a max psi rating moulded into the sidewall. That's a good starting point if you're running loaded.

We have the truck in my signature (a dually) with General Ameritrac LT 235/80R17 Load Range E tires (original to the truck), which have a maximum pressure of 80 psi. The sticker on the door jam says that for a maximum load, tires should be 60 psi front, 65 psi rear which is what we've been running for almost 26,000 miles (both towing and solo). So far, we've had no unusual wear on any of the tires.

Hobopals,

Check your owners manual for the recommendations from Dodge. Most likely the front will not need adjusting but the rear pressure will need to change depending on the load. The best advice would be to weigh the vehicle, with and without the trailer. You could then use the tire manufacturers recommendations for pressure based on the actual load.

Thank you, Rif. I read the manual when I first got the truck and found that the instructions were a bit confusing. It referred me to the pressure inflation brochures, which I can't find because it was a used truck when purchased and must have been removed. Someone advised me to look on the door (would never have thought to look there) and assumed that max (85) meant that I should fill it not more than to about 80 to allow for expansion. (I have my own air compressor and check my tires often on both truck and trailer.) I took the truck in to Dodge and had them rotate the tires when I had my first tune-up after purchase. I asked them if the tires were filled correctly, and they said they were so I was comfortable though now I'm wondering whether they were referring to the pressure I had in them or whether they had put the proper pressure in after rotating. I just looked at the manual, again, and have read more about "load". I know approximately what my trailer weighs, but will weigh it, again. I'll have to look for scales. Then, I'll weigh my truck separately. I appreciate your advice and the time you took to post.

Linda, and Harry and Becky,

I saw "E" load on the tire as the guy was changing it. 60 psi is not far off the 40-50 the guy mentioned, but I have quite a bit of stuff in the bed which I probably should weight--tool box, blue tote, stove, etc. I ALWAYS check my tires before hitching up so I'll adjust for these things when I get my weights checked. Thank you for your advice and for taking the time to post.

Rather than thank each post, individually, let me thank everyone for advice and information. I have more to work with, now. I have Firestone Tansforce HT tires. I'm thinking that the missing "brochures" were specific to these tires. I'm armed with enough information, now, to figure out or get someone to help me figure out how to properly fill and maintain the tires. Once again, thank you to all for your responses. Escapees is a wonderful "place".

quote:

Originally posted by hobopals:
I just had a flat tire with my 2004 3500 Dodge Ram Diesel Truck. I was keeping my tires at about 80 psi according to what I was reading on the door (it said 85 psi max) and what other people have told me. The AAA service man said I should only have between 40-50 in the tires. I've been told different things by different people. I'd really appreciate advice from this group. It's my only vehicle. I pull a light weight trailer when I go camping. Any advice would be appreciated regarding tire pressure when towing and not towing. Thank you in advance for any information you share.

Everybody has their own personal opinion on this subject..

The following is my personal opinion which is based on ...

> many years as a commercial/professional truck driver,

> plus three times that many years as an RVer, hauling, towing or driving RVs around America....

The AAA man is correct..about reducing pressure is pickup truck tires when not towing or hauling a heavy load...

Please remember that we are NOT talking about large commercial "Tractor Trailer" trucks nor Motor Homes... We are talking about the average and typical pick-up truck used in America..

Too many people think that just because the stamp on the side of a tire says inflate to "XX" psi, that they must always keep the pressure at "XX" psi..

This is only half right...

These people are confusing a typical "Car Tire" with A heavy duty "Truck Tire"

With the typical CAR tire,, YES, keep the pressure at the recommended PSI for both safety and tire life..

BUT ... for the heavy duty tires mounted on the typical pickup truck, that is not necessarily correct..

Your pickup truck tires are most likely either 8 ply or 10 ply... which means that they have heavy duty, stiff sidewalls..

If you are not hauling a heavy load or pulling a trailer with a heavy tongue weight, you do NOT need to keep your truck tires inflated to their maximum allowed PSI.. (80 psi)

Like most of you folks, I have hauled many heavy loads in the bed of a pickup truck over the years, including a couple of truck campers ...

and I have pulled all types of trailers,... small, big, short, long, enclosed, open bed, travel trailer, 5th wheel trailer,etc..

with their gross weight ranging from 500 lbs up to 19,000 lbs in weight.

I've pulled them all over the USA and in all types of terrain and weather...

And when I carried a heavy load in the bed or towed a trailer with a heavy tongue weight, I always inflated my tires to recommended PSI according to the tire manufacturers.

BUT.... BUT.... as soon as I got rid of the heavy load, I immediately dropped the tire pressure down to about 50/60 PSI...

At about 50/60 PSI, the average 10 or 12 ply truck tire is inflated enough to ...

> maintain the required surface area contact with the road,

> the lower PSI will NOT cause excessive heat buildup,

> the lower PSI will NOT cause excessive wear on the tire,

> and the lower PSI will actually give a longer lifespan to the tires.

NOTE:.... I am NOT speaking about running a heavy duty truck tires at 32 psi like a car tire...... The minimum for a truck tire should never be lower than 50 PSI..

I am saying that a typical heavy duty pickup tire can be safely ran with about a (±) 25% reduction in PSI with no loss of safety and with no harm to the tires when the truck is not carrying a load.

25% of 80 = 20
80 psi minus 20 psi = 60 psi

Once again, this is my personal opinion based on my own observations as well as information I have acquired from talking to tire retailers and tire manufacturers over the years.

But as always, to each his own...

Respectfully,
John

I have a crew cab long bed diesel dually with E range tires all the way around.

The fronts I keep at 80psi, the max listed on the sidewall. I don't figure the front changes all that much between fully loaded and empty with that big diesel being what the front tires are hauling around all the time. I like the way the tires sit on the pavement, not too rigid, not to squatted.

When loaded (12k# fiver), I generally run about 70psi in the rear duals. (I'd run higher if the pin weight of the fiver was higher.) If empty for a while, I'll drop them back to around 50psi.

That's my own preference. Less pressure gives a smoother ride when empty but less fuel economy.

My sticker says 60psi for both front and rear but I really have to wonder where they came up with those numbers. At 60psi, I'm sure the front would ride a little smoother but the tires would squat way more than I'd like. And when empty, 60psi is too much for the rear. Looking at inflation tables and the weight that's actually being carried back there when empty, I could drop it down to maybe 40psi. (I think I have it somewhere around 50psi at the moment, and they squat considerably less than the fronts at 80psi.

I don't go over the max psi printed on the tire sidewall.

Just telling you my own thinking, right or wrong.

Interesting topic.

Brian

A fun test, get a couple sheets of paper and your jack, park on a semi-smooth surface (chunky asphalt works best) and run the tires up to the maximum pressure. Let the tires down on the first sheet of paper, after a minute jack it back up. Now drop the pressure and switch in the second sheet of paper, turn the tire a half turn to get a fresh dirty area, lower the truck again and let it sit for a minute before going back up.

Now compare the two sheets of paper, look not only for the dirty tire print but for the pressure imprints the tire forced into the paper. On my truck the dirty spot was much smaller, didn't include either outside rib and was shorter front to back. the imprints were an even smaller area inside the dirty area.

This works best with fresh tires that haven't had the centers worn down but even then the results can prove educational.

quote:

Originally posted by hobopals:
I just had a flat tire with my 2004 3500 Dodge Ram Diesel Truck

I also have a 04 3500 Dodge Ram Diesel Duelly truck and run 55psi front and 60psi in the duels with over 40k miles and have 30% rubber left and no visable signs of over or under inflation. I pull a 5th wheel at 15k loaded.I will replace the tires before winter not because the are worn out but the check marks from the Arizona sun tells me to get new ones..

This Firestone/Bridgestone tire care pdf pamphlet is good to keep around for reference.

John, it is your opinion, and I like it. Sounds like the voice of experience in the real world to me.
I run the rears tires at 60psi continually. This is the recommended psi for dual tires on my truck, and is within the safe limits for hauling my 5er. Like Brian I keep the fronts at sidewall maximum, and they are wearing evenly- if my depth gage is correct.
I do keep in mind that the Rubber Industry says over 90% of all tire failures can be traced back to under-inflation.

Ah, yes, underinflation. I have the answer to that. Guess what it is?!! if you can't guess, check web site.......
Mike