towing air pressure

[ringneck]

2005 ram 3500 4by4,tires michlens 235 80 17.32 5thw tires ribs 235 85 16 ,11000 to 1200lbs.towing pressure for truck and 5thw,also pressure for not towing.tires max 80 lbs pressure.

 

[S.Morris]

Ringneck

I tow a 38 ft f/w T/H and roll about 21000lbs, with sig truck. Run 80psi front loaded or empty if you want tires to last on front of DRW. If I run more than 50psi in duals, it will take the centers out in fairly short order. If running empty for extended periods, I will drop rears to 38. Ran lots of miles for lots of years with this regimen and has worked well for me . YMMV
Keep in mind I do not run in extreme heat ever in my neck of the woods, and often travel in winter conditions heading to warmer climates.

 

[ringneck]

thanks for reply,so you run 80 psi on your ram and cougar loaded.unloaded you run 80 in front of truck and 50 to 38 empty,wright.

 

[Camperman]

On our 5er, I run 80 psi. I follow the door jam sticker for truck air pressure, whether towing or solo. My factory Firestone Transforce HT's have 37,xxx miles, are at 7/32nds, and wearing evenly. I rotate truck tires every 7,500-8,000 miles. I follow the same miles for rotating RV tires. I also have the RV tires balanced.

 

[AH64ID]

I would hit the scales to see what you weigh but you shouldn't ever need more than 65 in the rears and 55-60 is probably a more realistic max.

The fronts only need about 65 but some folks get better wear at 75-80 psi. It's a bit higher than needed but if it wears better it probably doesn't come with some of the downfalls of over-inflation.

As for the trailer the scales are the best way to know, but until you can scale it I would run max pressure. Once you scale it you can determine if you can reduce the pressure or not.


You would probably get more replies if you worked on the punctuation and organization of your posts.

 

[Mingoglia]

At least on my truck, I'm running within a couple hundred pounds of max tire weight in the front, so I always run 80 loaded or not. I did for a period of time run 70 and I prematurely wore my edges. That was before I weighed my truck and realized just how heavy these beasts are. Before that I had a second gen, and I ran 65 in the front... but 2nd gens are much much lighter.

I run 50 in the back of mine, towing or not. In reality, I should run more like 40 unloaded but this is a good compromise for me since 70% of my time I'm towing anyway, and this way I don't have to mess with the air pressure. I'm not a fan of adjusting rear dual air pressure. I'm lazy.

 

[Cummins12V98]

I run 80 front ALWAYS, rear 65 towing 35 solo. The towing numbers are listed for max ratings. I think I am in that range.

 

[ringneck]

thanks everyone............

 

[Road Dog]

My '02 came with a Tire pressure bulletin. Your '05 is a little heavier and has a higher GVW but you get the idea.
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And more generally:
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[ringneck]

thanks road dog,thats what i needed.

 

[KATOOM]

ALWAYS run trailer ST tires at their maximum pressures when towing. They're not designed nor intended to run at lower pressure for comfort and/or wear conditions like LT tires are. Run ST tires lower than their maximum rated pressure and they'll run hot.

 

[AH64ID]

I always ran my ST Goodyear Marathons at the table pressure for the weight and never had any issues. I would go 10 psi above table for interstate trips in accordance with the Goodyear TSB.

IMHO, Goodyear publishes load tables for a reason. Goodyear obviously believes they can be ran at lower pressures at lower weights.

http://www.goodyearrvtires.com/pdfs/rv_inflation.pdf
https://www.tirerack.com/images/tires/goodyear/Marathon_Special_Trailer_Applications.pdf

 

[SnoKing]

2005 ram 3500 4by4,tires michlens 235 80 17.32 5thw tires ribs 235 85 16 ,11000 to 1200lbs.towing pressure for truck and 5thw,also pressure for not towing.tires max 80 lbs pressure.

XPS Ribs on a trailer of that weight will do fine at 70 lbs inflation. I ran mine at 71 with a 12.4K 5er. Snoking

 

[KATOOM]

I always ran my ST Goodyear Marathons at the table pressure for the weight and never had any issues. I would go 10 psi above table for interstate trips in accordance with the Goodyear TSB.

IMHO, Goodyear publishes load tables for a reason. Goodyear obviously believes they can be ran at lower pressures at lower weights.

http://www.goodyearrvtires.com/pdfs/rv_inflation.pdf
https://www.tirerack.com/images/tires/goodyear/Marathon_Special_Trailer_Applications.pdf

Interesting..... I'll have to do some checking in to this. I've always understood the tables to represent a "capacity" at a certain pressure rather than how to tailor the air pressures in conjunction with the load.

 

[KATOOM]

I was digging around looking to solid data but not many specifically state whether its good nor bad to run a trailer tire according to weight. But here's a few websites I did find that are specific about making sure to keep the air pressure in an ST tire inflated to maximum.

I'm not saying anyone is wrong but merely saying what I've been informed over the years. The accurate way to save ST tires is dont run them less than max psi, dont overload them, dont let them sit for long periods of time unmoved, keep them out of sun UV rays, make sure the axle alignment is straight, and ST tires should last a long time.

http://www.carlstargroup.com/cms_files/original/Trailer_Tires__Tips_Best_Practices.pdf

http://www.westmarine.com/WestAdvisor/Trailer-Tire-Basics

http://www.trailmastertrailers.com/pdf/proper_tire_care_safety.pdf

http://www.discounttire.com/dtcs/infoTrailerTireFacts.do

https://www.etrailer.com/faq-trailer-tire-frequently-asked-questions.aspx

 

[SnoKing]

I was digging around looking to solid data but not many specifically state whether its good nor bad to run a trailer tire according to weight. But here's a few websites I did find that are specific about making sure to keep the air pressure in an ST tire inflated to maximum.

I'm not saying anyone is wrong but merely saying what I've been informed over the years. The accurate way to save ST tires is dont run them less than max psi, dont overload them, dont let them sit for long periods of time unmoved, keep them out of sun UV rays, make sure the axle alignment is straight, and ST tires should last a long time.

http://www.carlstargroup.com/cms_files/original/Trailer_Tires__Tips_Best_Practices.pdf

http://www.westmarine.com/WestAdvisor/Trailer-Tire-Basics

http://www.trailmastertrailers.com/pdf/proper_tire_care_safety.pdf

http://www.discounttire.com/dtcs/infoTrailerTireFacts.do

https://www.etrailer.com/faq-trailer-tire-frequently-asked-questions.aspx

Your theory might work for a light trailer. It however falls on it's face on most heavier trailers. SNOKING

 

[KATOOM]

Actually the exact opposite would be the case..... A heavy trailer would have no reason to "tailor" the pressure according to a weight table but rather a lighter trailer could run a lesser value being less likely to generate more sidewall heat.

I run a TPMS and making sure my tires are running as cool as possible is what matters to me. I could care less if my camp trailer, car hauler, or dump trailer are riding smoother.

 

[AH64ID]

The issue with all of those websites is that none of them manufacture tires. The tire manufacturers I have researched want proper pressure for the load.

Overinflation leads to decreased traction and tire life, but is an easier thing to tell people than go weigh and look at a chart.

 

[KATOOM]

Well, Carlisle tire was one of the links.
West Marine is a huge retailer for boat trailer equipment
Trailmaster makes the trailers which ride on the tires they're recommending proper procedure for.
Discount tire is gigantic and sells loads of ST tires.
And eTrailer is a major internet based trailer equipment supplier of not only components but trailer tires and wheel combo's.

AH64ID, you and I tend to agree on most topics but I'm not sure I'd discredit the validity in any of those above links..... Yes, I agree that Goodyear is listing a pressure chart as so does most tire manufactures, but again I'm not sure I'd say with no uncertainty that those charts are there to reference more than just the simple load capacities as the tire pressure changes. Again, I'm intrigued by this and maybe I'll see what I get out of directly contacting various tire manufactures regarding ST tire pressures.

 

[AH64ID]

I did miss the Carlisle one.

What I have noticed is many recommendations are based on the simplest answer which isn't always the most correct one.

All of the articles state that over-inflation is bad, so what is the definition of over-inflated. From what I gather it's more air than is needed for the speed/load, but it also appears to be tire manufacturer dependent.

I don't run ST's anymore but if I still ran the Marathon I wouldn't hesitate to run that according to the Goodyear load/inflation tables.

Most tire failures are from under-inflation and many of them are on ST tires. The easiest answer is to air them to max and not worry about it, but I prefer the additional braking and ride qualities of following the tables, and generally there is a noticeable difference. When I am making multiple runs with a dump trailer I don't change the air every leg of the trip, but I do have to be much more careful with the brakes and trailer stability on the way back to the quarry than on the way home.

I would be curious what other manufacturers have to say as well. There are some cheap scary ST's out there, that's for sure!