First off - yes, I still have the Marathons. The trailer is only two years old and the tires only have about 3,000 miles on them and all are dated 2011. Should I keep them? Still not sure with all of the bad press about them and others that have had issues. I had them on my last 5er too and never had an issue. I had about 15,000 on that set when I changed them out due more to the amount of time they had been on the trailer (almost 5 years) than anything else. I check my tires and lug nuts before each trip, normally each stop at a rest area or the like and I have a TST TPMS (507). I know the 507 will not necessarily save me from a blow out damaging the trailer, but it is another level of "comfort" to monitor my tires.
Here is the question- I know "the book" says to check them "cold" and maintain 80 PSI (one tech document says 85 PSI but I have not done that yet). My question is-what does "cold" mean? The mornings around here (near Seattle) this time of year are sometimes a bit chilly. I am normally checking pressures when it is between 45 and 55 outside and after the trailer has been sitting for at least a few days. The pressure at that point on all 4 "on the road" tires is normally 76-78 PSI by both the TST and a tire gage. Once they get warmed up during the continued cooler days on the road to around 75 degrees, the pressure on all 4 comes up to 87-88 PSI and stays constant. So, should I bring them all up to 80 PSI when the temperature is less that 50 outside? I know, I know, don't over think it. What's 2 or 3 PSI between friends?
I guess I am a bit anal retentive with the tires because I really like to see all 4 reading the exact same pressure when I am going down the road. Any thoughts?