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View Full Version : What tire pressure are you running on your trailer tires?



jbeletti
08-24-2006, 04:55 PM
Not trying to put anyone on the spot here. And Jeff posted some great articles in other threads in this forum back in 2004.

But in practice, I am wondering what some people are running as I am considering a change on my trailer.

With my OEM supplied Load Boss tires (ST 235/85-R16 load range G), I kept them at their max cold rate of 110 PSI.

Looking at my actual tire loading (trailer 4 from the image in the 2006 Rally Trailer Weights post (//heartlandowners.org/showpost.php?p=7420&postcount=2)), my door-side loading is the lightest with both tires at 2925. The off-door-side is 3075 (front axle) and 3150 (rear axle).

Using the guidline from load/inflation tables of inflating all tires to the load of the heaviest loaded tire, I would target 3150.

That said, looking at the attached load/inflation table for single wheel configuration, could I really run at 85 PSI? While I would love to run at a softer inflation for maybe a better riding rear-end of the coach, I am thinking it is not a good idea.

Maybe adding 10% and running at 94 PSI?? Anyone have any thoughts on this?

Thanks,

Jim

BluegrassMan
08-24-2006, 06:17 PM
Jim:
As I am NOT a trained technician in the tire field, I can only offer my thoughts on this. Any time that a tire is in use in it's loaded configuration, it should be in it's Max pressure COLD setting. The reason I think this is tires with lower pressure run at higher temperatures, have more rolling resistance, more sidewall flex in turning etc.
I have asked why truckers hit their tires with a "tire club", It is the way the club bounces back tells them of a LOW pressure one. They in turn run hot and "delaminate" to the GATORS we dodge on the interstate. I went to the NAPA store and bought a good comercial tire guage before going on vacation this month. Good luck in your search for tire truths.

jpmorgan37
08-24-2006, 08:13 PM
Jim;
I have to agree with Denny. From everything that I have read from tire manufacturers, and what Stacy told us at the Rally, it is in the tires best interest (and ours) to run at the max rated pressure. They run cooler at 110 psi (cold). I would love to run softer just for the smoother ride but don't want to take the chance, especially in the summer temps.
John

BigBlue
08-24-2006, 08:39 PM
I run my tires at 90 lbs psi which should allow the tires to support 3000 lbs for each tire.
They did a tire segment on RV Today with I believe GoodYear engineers. They weighed each axle of the test trailer and demonstrated how the load varies from front to back if the trailer is not level. Raising the hitch an inch changed the weight on the two axles about 250 lbs if I remember it correctly. Surprising.
They also demonstrated the use of the inflation tables. The GoodYear engineer indicated that you should run the tire at the pressure listed one column up from the weight you weighed. For example if the weight you measured indicated you should have 85 lbs in the tire then you should go to the next column which in their example was 90 lbs. That's the pressure you'd put in.

Ken Washington
08-24-2006, 09:48 PM
Jim, I have never agreed with max preasure unless you have max load. I run 95 psi in my GC and they look fine and don't heat up. Ware looks even also. You wouldn't run max air in your auto because of ruff ride and wearing in the middle would you? I think the danger with trailers is under inflation in relation to load.

davebennington
08-25-2006, 06:57 AM
Jim,

I run 100 lbs cold in the trailer tires (load Boss) and at every stop I check the heat on each tire with a hand held info-red thermometer. So far on the hottest day after running 60 to 65 MPH the highest temp reading was 122 degrees. Now the problem is I am not sure if this is a good thing or not, I put a mental limit of 150 degrees before I would start to be concerned. LOL

Dave:)

Jim_1899
08-26-2006, 01:39 PM
I am getting ready to go to the my Bighorn today and check my tires. I actually skipped checking them for the last two trips and spent some time looking at the chart. I need to find out my weight especially since buying it in April we keep adding more things. Thanks for the reminder. My next post will be #20 and I think I will be a member of the forum.