Tire Pressure

[TopoTony]

I just picked up a pre-owned '21 Hideout 174RK. The tires say max 80psi, the sticker on the unit says 80psi. The current pressure is 70. I thought there should be a recommended, but all I see is the max stated on the tires and on the side sticker. Thanks for any advise on this. Sorry if this has been discussed...couldn't seem to find my specific details.
https://www.keystoneforums.com/forum...1&d=1632244101


https://www.keystoneforums.com/forum...1&d=1632244101

[wiredgeorge]

Load range E tires need to be filled to 80 PSI else they will not support the weight they are manufactured to support. This is especially true on ST (special trailer) tires.

[TopoTony]

Thanks...the previous owner was not very attentive to quite a few things, and I see we can add tire pressure to the list.



I'll fire up my compressor. Is there any advise on filling them? Generally, it's a straight forward thing...put the hose on and pump it up, checking the pressure after short bursts of filling, until I reach 80. But, I've occasionally seen reports of people being injured, and I've never pumped up a tire to such high psi.


thanks again

Originally Posted by wiredgeorge

Load range E tires need to be filled to 80 PSI else they will not support the weight they are manufactured to support. This is especially true on ST (special trailer) tires.

[wiredgeorge]

Originally Posted by TopoTony

Thanks...the previous owner was not very attentive to quite a few things, and I see we can add tire pressure to the list.



I'll fire up my compressor. Is there any advise on filling them? Generally, it's a straight forward thing...put the hose on and pump it up, checking the pressure after short bursts of filling, until I reach 80. But, I've occasionally seen reports of people being injured, and I've never pumped up a tire to such high psi.


thanks again

Make sure your compressor regulator is set to a value over 80 PSI and use a good pressure gauge. I have quite a few air chucks with built in pressure gauges and these are really inaccurate. I use a Slime brand digital gauge. Air the tires when they are cold. I doubt you will need to feel in any danger. Next, read the threads on TPMS systems. There are usually several floating around and lots of good recommendations. A blow out on a trailer tire WILL cause extensive damage to your trailer. Last, you didn't mention what brand and date code are on your tires. The date code is generally in an oval on the sidewall with four numbers representing (first two) week in year of manufacture and second two year. So 3520 means 35th week of 2020 manufacture date. Camper tires don't wear out generally but age out and most cautious folks replace tires after 3 years. Doesn't matter if the trailer has few miles; age kills them and sunlight so many folks also cover their tires if they park outside.

[TopoTony]

Great..thanks. The date code is 1820, so, I'd think these are still worthy. I'll check out the TPMS stuff.

[travelin texans]

Always check & adjust pressures in morning before you travel inflating to the cold pressure as indicated on the sidewall.

[Javi]

Just a note... if the tires were filled to 80 psi at say 90 degrees and the current air temp is say 75 it is not unusual to see a drop of 10 psi..

[JRTJH]

Additionally, previous "abuse" by towing a heavy trailer with tires not properly inflated can damage the tires....

For you, those tires are an "unknown" and as you indicated, the previous owner was "selectively negligent in a variety of maintenance actions"... If he towed the trailer with underinflated tires and if they were damaged by that underinflation, you may not be able to rely on them as being "safe at the rated pressure"....

With "used tires in an unknown status" you might find it advantageous to just "take the hit and buy new tires that have a known quality"....

Tire safety is much more than just "They aren't outdated yet".....

[CWtheMan]

The USTMA says any tire operated at 80% of its recommended cold inflation pressures is in a "run flat" condition. The past owner was getting close and may have damaged the tires. If they are a few years old I would replace them with some tires sized at ST225/75R15 that have a load range that will provide at least 15% in load capacity reserves above the vehicle’s certified GAWRs.

[flybouy]

You have been given good advice. I'll just add one thing that I've found that makes "airing up" easy. First off the TPMS. I had a early system by Tire Minder. It worked but it would not read unless either I removed and reinstalled the sendor or the tire was rotating. I bought the TST 507 system because it will read all the time.

That said, I now know the tire pressures before starting out. Now back to my "hack" if you will. I have a coiled hose with quick releases that I attach to male QR, then a 1/4" ball valve, then a mini regulator, then a screw on inflation valve that screws on to the tire valve. I screww on the setup to the tire with the valve off. After it's secure I turn the valve on. The set the pressure to around 80.5 psi.to compensate for the minimal amount of air loss while removing it from the valve stem. No worries about over or under inflation and I don’t need to monitor the process. This works for me, YMMV.

[Roper46]

Originally Posted by flybouy

You have been given good advice. I'll just add one thing that I've found that makes "airing up" easy. First off the TPMS. I had a early system by Tire Minder. It worked but it would not read unless either I removed and reinstalled the sendor or the tire was rotating. I bought the TST 507 system because it will read all the time.

My TireMinder has a function on the monitor of holding the center & right button down until it beeps, which resets the indicated tires pressires to zero. It then reaquires all tire pressure readings. This sometimes takes ten to fifteen minutes.

I activate this function before I start towing for the day. It's a really nice function I discovered in the manual.

[wegone]

The sticker on my 2019 Bullet says 65 PSI cold, not 80.

How is this factored in then?
Why one pressure for one, and not the other?
Little confused here.

[sourdough]

Originally Posted by Island Eddie

The sticker on my 2019 Bullet says 65 PSI cold, not 80.

How is this factored in then?
Why one pressure for one, and not the other?
Little confused here.

What tire size and load range do you have? 225/75r15? If LRD it IS 65psi.

Edit: If you would go to the user CP in the upper left hand corner of the page and fill in your signature with trailer and TV info it helps get accurate answers and prevents a zillion needless questions as mine above.

[wegone]

OK. thanks...I will do that...however, I still like coming here to chit chat

[TopoTony]

Is there a recommended portable compressor? My Bostitch is way to big and heavy to tote with us. Anyone use this Ryobi, listed on Amazon?
Ryobi 18-Volt ONE+ Cordless 1 Gal. Portable Air Compressor

[sourdough]

Originally Posted by Island Eddie

OK. thanks...I will do that...however, I still like coming here to chit chat

Chit chat away, we enjoy it as well!

[jadatis]

What is your GVWR, and what are rhe GAWR's of your 2 axles?
Need that to calculate a pressure for you, with maximum reserve, without bumping.

[Miloski]

Good advice but don’t jump on new tires. Have them checked out by a reputable tire shop. 70psi could be from setting or they ran light on carry weight. If they’re not cracking or have have even wear then mostly they’re fine. Most uneven wear is from sharp jackknifing and sharp turns. Round them off whenever possible.

[TopoTony]

GVWR 5200
Each axle 5200

I put in 78psi. Checking them now, after traveling, they are both down 5 lbs. However, we descended from 2800’ elevation to sea level. Wonder if that is the cause of the psi loss?

My much bigger problem is that the trailer brakes aren’t working. I have checked So many things troubleshooting… adjusted brakes, traced current, etc. The Curt controller does not have any problems showing. I can hear the brakes buzzing when applying the manual controller switch. Have not actually tested again while moving. Jacked up the trailer and spun the wheel, but I think you have to be going about 20mph for a test.

Originally Posted by jadatis

What is your GVWR, and what are rhe GAWR's of your 2 axles?
Need that to calculate a pressure for you, with maximum reserve, without bumping.

[jadatis]

Dont you mean 2500 each axle? Or the GVWR must be wrong.

And altitude only gives 2 psi/1mile , with tmps you then read lower pressure then the gauge, and on sea level with gauge then same lower pressure as tmps .