Recommended tire pressure for 5th wheel trailer

[Arndog]

What is recommended tire pressure for my 5th wheel? Running Good Year Endurance tires on my Signature Ultra Lite (6600 lbs dry and approx. 8600 loaded)...sticker on 5th wheel states 50 psi cold and max cold pressure on tire states 80 psi. That is a big range! Suggestions?

[SeaDog]

I'm going to assume your rig came with class C tires and not the Endurance tires. Trailer tires are normally inflated to the max sidewall pressure cold.

[NMWildcat]

Originally Posted by Arndog

What is recommended tire pressure for my 5th wheel? Running Good Year Endurance tires on my Signature Ultra Lite (6600 lbs dry and approx. 8600 loaded)...sticker on 5th wheel states 50 psi cold and max cold pressure on tire states 80 psi. That is a big range! Suggestions?

Sounds like the tires are not the same size/load range as the originals that are described on the sticker?
Also, this topic is a regular, well beaten, subject. Search for some other lengthy threads and get more comments that you will need.

[Arndog]

Yes, came with different tires, but I always thought you go with the pressure on the vehicle/trailer sticker...is that not correct?

[NMWildcat]

Originally Posted by Arndog

Yes, came with different tires, but I always thought you go with the pressure on the vehicle/trailer sticker...is that not correct?

For the original size tires specified on the sticker. Not a different size/load range.
Most of us run the max cold psi on the side of the tire for towables. Period.
Others will reduce that psi according to load tables for the particular tire. They say they do this for a better ride. It's a towable, ride has never been a concern of mine.

[TitanMike]

Originally Posted by NMWildcat

For the original size tires specified on the sticker. Not a different size/load range.
Most of us run the max cold psi on the side of the tire for towables. Period.
Others will reduce that psi according to load tables for the particular tire. They say they do this for a better ride. It's a towable, ride has never been a concern of mine.

Not necessarily for better ride but more tire contact with the road for braking. If you inflate a tire more than necessary to carry the rated load of the trailer the tire isn't necessarily providing all the traction needed to stop properly.

There's a reason why tire load tables are published.

[NMWildcat]

Originally Posted by TitanMike

Not necessarily for better ride but more tire contact with the road for braking. If you inflate a tire more than necessary to carry the rated load of the trailer the tire isn't necessarily providing all the traction needed to stop properly.

There's a reason why tire load tables are published.

I could see this possibly making sense if you upgrade to a tire with considerably more load capability than the trailer weight, or for a very light trailer. Then you will see uneven wear patterns (center).
But for heavier trailers, I really don't see psi set by actual load vs max cold psi, making enough difference in actual tire contact to affect braking. But, that's just me and my experience.
I always go up a load range from original, and always use max cold psi on the tire, for towable RVs. I'm too lazy to determine actual weight per trip and adjust psi accordingly to a table. Works for me, everyone has to decide for themselves.

[TitanMike]

Originally Posted by NMWildcat

I could see this possibly making sense if you upgrade to a tire with considerably more load capability than the trailer weight, or for a very light trailer. Then you will see uneven wear patterns (center).
But for heavier trailers, I really don't see psi set by actual load vs max cold psi, making enough difference in actual tire contact to affect braking. But, that's just me and my experience.
I always go up a load range from original, and always use max cold psi on the tire, for towable RVs. I'm too lazy to determine actual weight per trip and adjust psi accordingly to a table. Works for me, everyone has to decide for themselves.

This apparently is the case with the OP's situation. Sticker calls for 50 PSI and tire sidewall shows 80 PSI max. That's a 60% increase in pressure without a corresponding increase in load weight.

If one has a heavier trailer that came with a marginal tire then upgrading to the next load rating makes sense. This often means an increase from 50 PSI to 65 PSI (LR-C to LR-D, average) which is only a 30% increase in pressure which might match the trailer weight better than the original tire.

The Mythbuster's motto of "Anything worth doing is worth overdoing" doesn't always hold true with tires.

[Arndog]

Found a load/inflation table from Good Year for their Endurance tire at https://www.goodyearrvtires.com/pdfs/rv_inflation.pdf. Shows the pressure I need for my max load is 50psi.

[rlh1957]

Always go with the Max Cold Pressure on the Tires and not on the rig.

[Walholler]

Why do people read something into what is written on the sidewall. It does not say to inflate to 80 psi, it says inflate to a max of 80 psi. That means do not exceed 80 psi. So if you are running 70 psi your fine because you have not exceeded the 80 psi. I personally run my tires, that are rated at 80 psi max, at 72 psi cold. When the tires warm up the pressure will be closer to 80 psi.

[dannyabear]

Originally Posted by Walholler

Why do people read something into what is written on the sidewall. It does not say to inflate to 80 psi, it says inflate to a max of 80 psi. That means do not exceed 80 psi. So if you are running 70 psi your fine because you have not exceeded the 80 psi. I personally run my tires, that are rated at 80 psi max, at 72 psi cold. When the tires warm up the pressure will be closer to 80 psi.

The increase in pressure because of heat buildup is calculated into the max pressure shown on sidewall

[TitanMike]

Originally Posted by rlh1957

Always go with the Max Cold Pressure on the Tires and not on the rig.

Not wise if one has jumped two load ranges (like from C to E).

Smart move is to take "Scale Weight" and add 10-15% then consult load/inflation table for the calculated weight.

If only going up one size (C-D or D-E) then it's OK to use sidewall pressure.


The tire was designed to carry a given load at a given pressure and provide proper contact with the road for grip and even wear. Over-inflating can actually make the tire more vulnerable to road hazards and cause trailer bounce more easily.

[dannyabear]

Maybe Tireman will post the article about 'inner ply shear' for those who missed it the other 20 times he posted it

[Airdale]

Originally Posted by Arndog

Yes, came with different tires, but I always thought you go with the pressure on the vehicle/trailer sticker...is that not correct? Yes, that is correct for the original tires and any replacements of the same designated size.

The following information is from tire industry standards (USTMA).

Replacement tires must provide a load capacity equal to or greater than the Original Equipment tires provided. If the replacement tires are the same designated size as the OE tires, the tire placard is valid for both the OE tires and the replacement tires. In other words, a ST225/75R15 LRE will provide the same load capacity at 50 PSI as a LRC with that size designation.

When using a plus sized tire size such as a ST235/85R16 LRE to replace a ST235/80R16 LRE, load inflation charts for both designated sizes will be needed.

When using replacement tires with higher load ranges or plus sized tires that provide more load capacity it’s a common practice to insure you gain at least 10% in load capacity reserves from the replacements. To do that you need to use load inflation charts to insure your new tires are inflated to a load capacity equal to the OE tires and then add 10%- 15% of extra load capacity with your inflation pressures.

NHTSA allows the use of an auxiliary tire label to identify the new tire sizes and recommended inflation pressures. That placard should be placed adjacent to the original tire placard.

The PSI value found on the sidewalls of all tires is often misunderstood. It is there to inform the user that the tire is providing its maximum load capacity at that cold tire inflation pressure.

[TitanMike]

Originally Posted by Airdale

The PSI value found on the sidewalls of all tires is often misunderstood. It is there to inform the user that the tire is providing its maximum load capacity at that cold tire inflation pressure.

And the primary reason for this misunderstanding among Trailer Owners is that the manufacturer almost always puts a tire on that just meets the load requirement for trailer axles. The axles will always be the limiting factor so why put more tire on than necessary (at greater expense) and then the suggested inflation on the vehicle sticker will equal what's on the sidewall.

This is why we see LR-C tires capable of 1760 lbs at 50 psi installed on 3500 lb rated axles.

[DieselDrax]

Originally Posted by rlh1957

Always go with the Max Cold Pressure on the Tires and not on the rig.

So you run the sidewall PSI with the tires on your Ford? How's that ride?

I don't understand the folks that say to run the sidewall PSI and then don't actually follow their own advice for all their tires on all their vehicles.

Follow the tire placard and inflation charts. Sidewall PSI is the pressure needed for MAX load, not ALL loads.

[Maggot]

Originally Posted by DieselDrax

So you run the sidewall PSI with the tires on your Ford? How's that ride?

I don't understand the folks that say to run the sidewall PSI and then don't actually follow their own advice for all their tires on all their vehicles.

Follow the tire placard and inflation charts. Sidewall PSI is the pressure needed for MAX load, not ALL loads.

My door sticker says front 50psi and the rear 80. Tires say 80 both on truck and rig, so 80 all around for me.



Ride empty is stout but with camper it is fine. I only get about 10-15K miles out of a set of truck tires as it is not my daily driver and they age out before wear out.



One thing that is unknown with OP is, was his tires changed to the E rating and if it was is his wheel able to take the 80psi. Probably so but just a thought. My take for the OP is run the 80psi like the side wall and roll it down the road.

[5picker]

This is yet another tire thread where those that believe running the MAX pressure on the sidewall is always the correct answer.

And then... we have those that believe running the pressure from the manufacturers load chart is the correct answer.

Finally we have those believing the pressure should only be what is on the manufacturers sticker as long as you have the OEM tire size.

I'll never live long enough for any of the three to agree on anything other than what THEY believe to be correct. Tire threads are more so 'closed loop' than any other forum thread besides diesel-vs-gas.

This is one of those topics where I feel bad for the ones that ask the question because we really never help them. They turn into way too much misinformation and utter confusion you'll never get a consensus.

My suggestion to the OP... read as much as you can stomach (and there's days worth of reading!) and try to come to a conclusion that YOU are comfortable with.

[valleyduo]

Originally Posted by Arndog

Found a load/inflation table from Good Year for their Endurance tire at https://www.goodyearrvtires.com/pdfs/rv_inflation.pdf. Shows the pressure I need for my max load is 50psi.

Run the 50 PSI then and all should be good. You've got lot's of room to play with til your max PSI, so if you don't like the way it rides at 50 then try 55 and so on til you get a ride you like. Just don't go below 50.