tire pressure

[rally]

does anyone put MORE then the recommended cold tire psi in rear tires when hooked up to a 5-er? My truck says 60 psi but i think 5lbs would be better

[Country Campers]

I do not . I use the label on the door jam of the truck for both front and rear.

Brian

[howson]

does anyone put MORE then the recommended cold tire psi in rear tires when hooked up to a 5-er? My truck says 60 psi but i think 5lbs would be better

No. I also follow the door jamb recommended pressures when towing.

[Cate&Rob]

If there is room between the label spec and the max pressure on the tire sidewall, anywhere in this range should be OK. I used to do this on my HDPP F150 with factory 80 psi tires and a label spec of 60 psi.

Rob

[rally]

OK, here is another one. On my Lippert TPM I put correct PSI in then it wants max/ min temp of tire. what is that for/?? How do know how cold i\I want the tire? Also what is the range PSI y'all use? I need to find a vid I think LOL

[Scott'n'Wendy]

Well, I ignore the label PSI rating and go by the tire rating. When towing my tires are at max pressure. Truck and trailer.
For my 80 psi trailer tires I have max pressure on TPMS at 90psi. I only set off the high alarm once when going from freezing temps in MN to comfortable temps in Kansas in one day. So with cold inflation at 80 at the freezing point, I hit 92psi at 70mph in 60-65* temps.

[Jkwilson]

OK, here is another one. On my Lippert TPM I put correct PSI in then it wants max/ min temp of tire. what is that for/?? How do know how cold i\I want the tire? Also what is the range PSI y'all use? I need to find a vid I think LOL

158 maximum temperature and 20% over normal pressure is the norm for the alarms. I set my low pressure alarm close to the normal pressure because I want to know the first hint of a problem. I have the low pressure alert at 76 for my 80psi tires, high at 96psi.

[ThePowells]

I run what the manufacturer sez for the weight. Empty I rum 35 PSI.

[TucsonJim]

I've never understood the "cold" tire inflation number on the tire. Cold for me on an August morning in Arizona may be 90°F. But a person in West Yellowstone may be at 40°F. If we both inflate to 80 PSI, our tire pressure will be quite a bit different if I drive to a cooler climate, or they drive where it's warmer. I wish the tire manufacturers would specify an actual temperature. For example, 80 PSI at 70°F. And then you could use a compensation table to properly inflate the tires.

[Jkwilson]

I've never understood the "cold" tire inflation number on the tire. Cold for me on an August morning in Arizona may be 90°F. But a person in West Yellowstone may be at 40°F. If we both inflate to 80 PSI, our tire pressure will be quite a bit different if I drive to a cooler climate, or they drive where it's warmer. I wish the tire manufacturers would specify an actual temperature. For example, 80 PSI at 70°F. And then you could use a compensation table to properly inflate the tires.

That wouldn’t work. The tire needs at least 80psi to hold its rated weight regardless of the ambient temperature.

[TucsonJim]

That wouldn’t work. The tire needs at least 80psi to hold its rated weight regardless of the ambient temperature.

I hear you. But what does a tire manufacturer define as "cold" on the sidewall?

Jim

[howson]

I hear you. But what does a tire manufacturer define as "cold" on the sidewall?

Jim

The same as the current ambient temperature?

[hduring]

I’ve tried to be smarter with checking tire pressure on our RV and truck. While using ambient outside temperature is what I use, I also try and check PSI/fill before the sun hits the tires (that’s what ‘cold’ means to me) because i found skewed PSI readings when one side of the RV tires’ get the sun making them hotter than the other side where there is shade. It may be 50 degrees outside before the sun hits the tires, so I’ll fudge the air fill to about 74 PSI - 80 PSI being my ultimate goal. I will check the PSI throughout the day using the TPMS system (TST) and air pressure gauge. My air pressure gauge and VIAIR air pump to being really close on readings. Once the outside temps hit 70 degrees, I found the PSI to be on the shady side of the RV to be at 80 PSI, while the sunny side is around 83 PSI or more. I check in the evening when the ambient is around 60 degrees, and get around 77 PSI on all four RV tires. My TPMS has shown some tire high temps and high PSI driving in 95 ambient degrees, but I have the TPMS set for a high PSI at 96 (20% above 80 PSI) and high temp of 112 degrees (cannot remember the math I used for that). I also use tirepressure.org (calculator) for some additional temp / PSI info. I’m open to suggestions on a better way of doing this, but it seems to work and I get consistent readings of what PSI I want a few days later.

[TheNescios]

Having done a bunch of research on tires after figuring out my 5th wheel has what is referred to as "China Bombs", here is what I came up with.
"Cold" means the relative ambient temperature - and HDuring is on the right track with doing it before sunlight hits the tires - after monitoring the tire pressure & temperature with my Tire Minder TPMS there is a distinct difference between the side with sunlight and the side without. It's the rise in pressure from cold to running down the road at speed.
Regardless of what the door sticker says, go by the max pressure stamped on the tire and NEVER over inflate the tire - over inflation is a recipe for disaster.

Final part of this is inflation - just because the tire will carry 5,000 lbs. at 110 psi doesn't mean you should run 110 psi for your application.
If your RV is less than 20,000 lbs. fully loaded, you can reduce the inflation psi by the same factor as the max capacity less the actual weight being carried - but not by more than 85%.
The not less than 85% is from a tire manufacturer website, but I'm not recalling which one.

Will add in that I'm running a Tire Minder i10 TPMS and like how well it works that I use the same sensors on my pickup vs the manufacture tire monitoring system - it works VERY well monitoring the pressure and temperature of the tires.

[Jkwilson]

Having done a bunch of research on tires after figuring out my 5th wheel has what is referred to as "China Bombs", here is what I came up with.
"Cold" means the relative ambient temperature - and HDuring is on the right track with doing it before sunlight hits the tires - after monitoring the tire pressure & temperature with my Tire Minder TPMS there is a distinct difference between the side with sunlight and the side without. It's the rise in pressure from cold to running down the road at speed.
Regardless of what the door sticker says, go by the max pressure stamped on the tire and NEVER over inflate the tire - over inflation is a recipe for disaster.

Final part of this is inflation - just because the tire will carry 5,000 lbs. at 110 psi doesn't mean you should run 110 psi for your application.
If your RV is less than 20,000 lbs. fully loaded, you can reduce the inflation psi by the same factor as the max capacity less the actual weight being carried - but not by more than 85%.
The not less than 85% is from a tire manufacturer website, but I'm not recalling which one.

Will add in that I'm running a Tire Minder i10 TPMS and like how well it works that I use the same sensors on my pickup vs the manufacture tire monitoring system - it works VERY well monitoring the pressure and temperature of the tires.

One very important caveat on reducing pressure: You HAVE to know individual wheel loads and set your pressure on all tires to handle that weight. It’s not unusual for side to side weight distribution to be very uneven, and just dividing the total load by four can leave you under inflated on some tires.