Go Back   Keystone RV Forums > Keystone Tech Forums > Tires, Tires, Tires!
Click Here to Login

Notices

Reply
 
Thread Tools Display Modes
 
Old 10-10-2019, 01:55 PM   #61
jadatis
Member
 
Join Date: May 2013
Location: Holland ( Europe)
Posts: 50
There is a difference between maximum(allowed) cold pressure and what most think is max pressure, pressure written behind AT on sidewall, or belonging to loadrange.

The pressure behind AT, will call it AT- pressure furtheron, is the pressure for wich the maxload is determined, for a speed , mostly max speed of tire, but not always.

The maximum cold pressure, is the maximum cold the tiremaker allowes.

The rising of pressure by higher temp in tire is all calculated in in the system, so no problem if pressure rises by driving .

Once read from one of the specialists here, that teststandards are used in tire-desighn, that they have to stand a pressure of 2 to 3 times the AT-pressure. This is for a AT 80 psi tire 160 to 240 psi!!!!!!

In earlyer days tiremakers allowed higher then AT , but nowadays not anymore.

But this all tells us, that you easyly can smuggle a bit with that AT pressure, if needed for laws of nature. Only dont do that with an already damaged tire by overheating , by using to low pressure for the load on tire,only once, then the mechanical forces that tear the beginning cracks furter, only get larger, and tire will fail sooner, and high pressure is blamed.
__________________

jadatis is offline   Reply With Quote
Old 10-10-2019, 02:56 PM   #62
CWtheMan
Senior Member
 
CWtheMan's Avatar
 
Join Date: Feb 2010
Location: Taylors, SC
Posts: 1,554
Tire inflation pressures: There has to be a right way. Who defines the right way? Cold is cold. NHTSA defines cold tire inflation to be performed when the tires are cold,

If the vehicle has been setting in a covered garage for three hours, the tires are cold. If the vehicle has been parked at a campground at the Salton Sea for three hours, the tires are cold. If the vehicle is parked at Lake Tahoe for three hours, the tires are cold.

If the tires do not qualify for cold because they haven't set for three hours and you think the tires need inflation. Inflate them to the placard recommended inflation pressures. Later on, when the vehicle has had a chance to set for three hours, reset the inflation pressures.
__________________

__________________
An Old Navy Aircraft Mechanic that writes about tires.
Our rig. NC mountain pull-off. US-19.
http://www.irv2.com/photopost/showfull.php?photo=35007
CWtheMan is online now   Reply With Quote
Old 10-10-2019, 05:19 PM   #63
rcashdollar
Junior Member
 
Join Date: Sep 2019
Location: Erie
Posts: 22
A couple of months ago I bought a Cougar xlite 21RGS which has the original tires 225/75R/15D on it (date code 2013). I put it away for the winter but will replace with E rated tires in the spring before we use it again. Talking to Discount Tire they tell me that they don’t even stock the D’s since all they ever do is use the E’s. They recommended the 80 PSI and I would think going form an 8 ply (D) to a 10 ply (E) would be a benefit too. I asked whether the wheels are okay going to E’s and he didn’t think twice about saying it’d work. Is this sound right?
rcashdollar is offline   Reply With Quote
Old 10-10-2019, 05:48 PM   #64
sourdough
Site Team
 
Join Date: Feb 2014
Location: W. Texas
Posts: 7,556
With the size of your trailer I would sure check behind the wheels and see what they are rated for before upping to 80 psi. I am assuming you are meaning 21 RBS? With 2013 tires I would be in the tire store before I did anything else with the trailer as far as going anywhere.
__________________
Danny & Susan wife of 52 years
2014 Ram 2500 6.4 4x4 CC
2014 Cougar High Country 319RLS
sourdough is online now   Reply With Quote
Old 10-10-2019, 06:07 PM   #65
rcashdollar
Junior Member
 
Join Date: Sep 2019
Location: Erie
Posts: 22
Yes, 21RBS. I always thought the 5 year rule was crap and now I know better thanks to this forum. Like I mentioned I’ll put new tires on in the spring before we use it. I didn’t feel the need to buy new tires and let it sit there all winter.
__________________

rcashdollar is offline   Reply With Quote
Reply

Tags
tires

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

Powered by vBadvanced CMPS v3.2.3
Disclaimer:

This website is not affiliated with or endorsed by the Keystone RV Company or any of its affiliates in any way. Keystone RV® is a registered trademark of the Keystone RV Company.


All times are GMT -8. The time now is 01:47 PM.


Powered by vBulletin® Version 3.8.9
Copyright ©2000 - 2019, vBulletin Solutions, Inc.
×