Travel trailer Tire Super Thread

[backtrack15]

Originally Posted by jadatis

Answer to above post #18.

I also expected P-tires but are they XL/extraload/reinforced, or even yust Standard load.

SL AT 35/36 psi and XL// AT 41/42 psi, but sometimes 44psi.
If SL they advice above referencepressure cold, wich is not allowed for LT and ST tires anymore, but done for extra safety reserve.
On most P- tires they only give maximum allowed cold pressure of 44 to 51psi, and XL sometimes 60psi.

And howmany axles, or did you give that already? Also GAWR and GVWR?
Can you also give the exact sise and see if XL// on it, also maxload of tire?

Then I can get a better picture of the reserves your OEM tires give.

If the questions were for me, I don't have the non-ST Trail Guide tires referenced in the original post of this thread. My trailer came with ST tires rated at 2340 lbs/tire when inflated to 50 psi. My trailer has four tires and a scaled weight on the trailer axles (total for both) of 4080 lbs.

I believe the non-ST Trail Guide tires from the original post are 235/75R15XL and rated at about 2270 lbs/tire at 50 psi. Winnebago recommends 44 psi. Most Micro Minnie trailers with this tire (dual or single axles) have an axle rating (GAWR) of 3700 lbs or less.

I personally am most interested in hearing about people running the Endurance tires (E-rated) at less than the max pressure of 80 psi and/or the merits of running the non-ST Michelin Defender LTX M/S in 235/75R15 109T XL. I've always had great service from Michelin tires.

[jadatis]

Then the ST must be smaller sise then the XL, because only 1 LI step more, while going from 44psi( or even 41psi) to 50 psi. Expected 2 li steps higher in same sise 275/75R15 and even because of lower speed a few LI steps more.
Could not find a 2340lbs tire at 50 psi, in old and new Goodyear ST lists.

Will put your data in my spreadsheet, and will even lower maxload by 6 steps , to give highest pressure advice.

It comes to 27 psi for your 4080 lbs on 4 tires, using LI 104/ 1985lbs maxload a tire, so 6 LI steps degraded.
Did everything to get a high as possible pressure, so even if this seems extreme low, it has maximum reserve.

I assume topicstarter to have same OEM tires, but mayby using full GAWR , so mayby higher pressure for him calculated.

[backtrack15]

Originally Posted by jadatis

Then the ST must be smaller sise then the XL, because only 1 LI step more, while going from 44psi( or even 41psi) to 50 psi. Expected 2 li steps higher in same sise 275/75R15 and even because of lower speed a few LI steps more.
Could not find a 2340lbs tire at 50 psi, in old and new Goodyear ST lists.

Will put your data in my spreadsheet, and qill even lower maxload by 6 steps , to give highest pressure advice.

My ST tires are 235/75R15 Westlake CR857+ load range C. They are rated to 75 mph. Max load of 2340 lbs at 50 psi. You can see the D-rated version on etrailer.

[jadatis]

Answer to above post #23.

I know they are given maxload 2340 AT 50 psi, and max speed 75mph. But ST maxload is always calculated for 65mph.
That Is why I lowered it by 6 LI steps , to give it deflection needed for 99mph. All to give a high as possible pressure, with still no bumping.
All to show that the 27 psi is perfectly safe still.
In America they advice not to go lower then 26 psi.
In Europe 21 psi, but calculated loadcapacity that leads to higher pressure. My calc comes even to higher pressure.

[Itsthex]

Chiming in on this thread,

I have a Hike. It came with the Trail Guide ST tires, max 50PSI. So far so good, on and off road, but i've only gone maybe 300 miles.

What's the word on offroad tires for these trailers? Since it's so light, are standard all terrain tires for a light truck OK to run?

[jadatis]

If the maxload is for 99mph is enaugh for GAWR +11% , even a P-tire is enaugh, and those are better for the real offroad .

An ST needs 30% reserve to GAWR to give maximum reserve without bumping.

Why go for yust enaugh, if you can have max reserve.

Only thing is that LT needs higher loadrange to get same maxload as ST, P tire ( offroad eventually), needs larger sise to give same maxload.

In Backtrack15 case even the OEM XL P- tires can easyly carry the GAWR.