Originally Posted by TonyD
I used a temp gun. Tire pressures were up about 3.5 psi and that was a combination of temperature and increase in altitude. My tire were set to 78 psi out of max 80 and I was comfortable with the temps and pressure I observed.
Speed limits on the interstate is 75mph here. Driving any slower causes all sorts of problems with other drivers too eager to pass.
I decided to get L/T tires when I put brand new ST tires on my camper and had a tire delaminate 10 miles from my home. With ST tires, I drove 65mph in the far right lane so speed wasn't an issue; neither was tire pressure or loading. Not too long afterwards, I blew another ST trailer tire on my sled trailer. It was 25 deg F outside and I was driving 70mph. The tire that hadn't blown was cold so tire temp form excessive speed wasn't an issue. Ironically, both tires blew on the same section of I-25 but one heading S. Bound and the sled tire heading N. Bound.
The engineering math would indicate the average "c
emp" to be about 25F above the ambient when pressure was originally set with a 3.5 psi increase. TPMS temperature is not "CAT" with external sensors due to cooling from external air. IR guns can be way off due to critical nature of hitting the right spot on the shoulder with being off by as little as 1/8" resulting in readings being off by 20 to 50F
By "delamination" are you saying the belts & tread separated from the body of the tire and looked like this?
and you had no warning of air loss from your TPMS? Tread separations can usually be discovered many hundreds of miles before the tire comes apart if a close examination
Speed and load at he time of a separation is not an indicator of the root cause as this type of structural damage takes place over many months and thousands of miles of operation.
By "blew" do you mean there was a sidewall "Run low Flex Failure" that many call a "blowout" and looked like this
This type of failure occurs when the tire looses significant air pressure. This can occur due to cut, puncture or many times a leaking valve. This is why the use of metal valve caps with good sealing "O"rings at strongly recommended. Was the tire pressure set when ambient was 20F ?
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. 40 years experience as tire design engineer. Freelander 23QB on Chevy chassis is my RV. Giving seminars on RV Tire applications (not selling)@ FMCA Conventions. Next in Mar 2021 in Perry, GA