Tire Pressure.... again, sorry.

[100ton]

I am upgrading to E rated tires (Maxxis) on my 2005 5th wheel (CF29RK). I do not have an issue of the 5th wheel being overweight, in fact it's probably on the light side compared to many trailers. I am only upgrading to E rated tires to gain a little extra piece of mind.

My question is this, since the trailer is within the weight limits for my current D rated tires (225/75 R15, 2540 lbs. @ 65 PSI), I thinking that I might run the new D rated tires at 75 PSI (2720 lbs.) instead of the maximum 80 PSI (2830 lbs.) thereby providing a "softer" ride. What say you?

By the way, my current (aluminum) rims are rated for 80 PSI and I also have the Equa-Flex system.

Thanks for your input.

See you out there,

Robert

[geondebi]

I have load range E tires on my PP and run them at the max pressure as stated on the side of the tire. I have not had a problem with a soft ride, however, with some of the pot holes on the freeways it would bump things around.

[Hunter11]

I don't think 5 lbs of pressure in anE rated tire is going to make any difference in ride. Once you get the new tires try both pressures and see if you notice any difference.

[fixit5561]

I wou;d run them at max pressure if it was me. Thje rteason why is, when a tire is underinflated, it doesnt run flat to the road, it is cupped where it meets the road. What I mean by cupped is, the outer edges of the tire have more preassure on them because the tire in the middle isnt touching the orad as much because it is underinflated. What Im taling about is better explained on this website. http://www.topspeed.com/cars/gas-saving-tips/under-inflated-tires-cause-additional-fuel-consumption-ar29652/picture154278.html

[Hamops]

I don't see any reason to worry about running E rated tires at 70 to 75 PSI as long as all the tires are at the same pressure. What you need to do is to monitor the tire temperature. If the tires seem hot to the touch, then maybe bumping the pressure to the max is needed. Most trailer tires are the radial type as opposed to bias ply, and cupping should not be an issue. Twice on separate two occasions, I had to replace tires on the road. One setis E rated and the other setis D rated. (no choice in the matter) All the tires are pressurized to 65PSI. I havemonitored thetire temperatures with a heat temperature gun andfound them all to be about the sametemperature. (plus or minus 2 degrees F.)

[fixit5561]

Originally Posted by Hamops

Most trailer tires are the radial type as opposed to bias ply, and cupping should not be an issue.

Maybe Im not using the correct terminology by saying cupping. What I mean by cupping is thetire doesnt touch the road all the way across the tread pattern, the middle of thetire, while underinflated, doesnt touch the ground as hard as the outside edges which inturn makes the outside edges of the tire wear abnormally, and causesthe tire to run hotter as explained in the second paragraph in this article

http://www.icarumba.com/cobrands/contentmodules/resourcecenter/articles/icar_resourcecenter_articles_tirecare.asp







Edited by: fixit5561

[100ton]

Thanks to all that replied to my tire pressure question. I now have some (experienced) direction in this matter. This is one of those subjects that may not have one absolute answer. Unfortunately, asking this question to a tire dealer is like asking the IRS a tax question....... the answer many times depends upon who picks up the phone.In my experience, many of the tire dealers really don't want to give a definitive answer. CYA, I guess, in this day and age I really can't blame them. At this point I am leaning toward running the E's at max (80 PSI) and going from there. Thanks again.

Robert
Huntington Beach, California





Edited by: 100ton

[happycampers]

i would run them at the max pressure. the last trailer i had i ran them a little light for a softer ride and i had a blow out. now, always at 80psi. i check them every time i hitch up and long drives i check halfway thru the day. just my 2 cents.

[avvidclif]

I just bought (last week) the TST Tire Pressure Monitoring System. At $200 shipped (4 tire version) if it saves me one tire it almost paid for itself. Not counting damage to the trailer. The peace of mind it gave me rolling down the road has no price tag.



When you take a short trip and roll into your destination and the friend there asks "How long you been running on that flat?" and your reply is "What flat?" Get out and look and there is only the bead left of the right rear tire. Luckily no damage but the mind starts asking, "When did this happen and why didn't I know it?"



Uh, A/C and windows rolled up. Gotta be a better way, bought TPMS.

[Flyone]

All--keep in mind that tire inflation pressure is with cold tires. Inflate the tires to max or very near it when they are cold (unused).



Flyone