My tires hold 80 psi do I set my default to 80? It came from the factory at 72.4 psi and in a short ride, three of the tire alarms went off. They were all indicating 86 to 88 psi but temp was only 64 degrees. Please respond in elementary language, as I am not a techi!
I used my system for the first time this past Wednesday on a 250 mile trip. The ambient temp was in the high 60's when I checked and set each tire at 80 psi. By the time I had driven 100 miles or so the psi of each tire was approaching 90. After another 100 miles and the ambient temp increasing to the high 70's, the psi in each tire was 92'ish. I talked with friend that has had his system for awhile and he said this is normal for his tires.
I knew the tire pressure increased with temp, but I was surprised at the amount of the increase. I can't help but wonder what the psi will be when the summer ambient gets up to 100'ish.
I have been using a TST monitoring system for 5 years for 80PSI LT tires, and have set my upper limit at 93PSI and my lower limit at 70PSI. "IF" your tires say 80PSI, you should put 80PSI in them. I do know the TST system has a +/- 3PSI reading. When I was at the Phoenix GS ralley last month I stopped by the TST booth and asked if the +/- 3PSI was normal. Answer was yes.
2011 Arctic Fox 29-5T 5th Wheel
2011 Silverado HD 3500 6.6L Duramax Diesel Crew Cab
Short Bed 4X4 SRW LT
50gal Transfer Flow Aux. Tank
16K Valley Hitch w/bed saver
That is where I got mine. Guess I will have to try and figure this thing out! I am NOT mechanically inclined at all. I do keep 80 lbs in the tires. So, set the default ones to 93 and 70?
Check your tires 1st thing in the morning before using your truck. This would then be your "cold" tire temperature.
Set your parameters for 15% above and 10% below that tire temp. Those are the parameters TST suggests but we have found that setting our parameters 20% above and 15% below the cold tire temps works best for us. Using these parameters we are still fully covered but don't get false alarm readings. I hope this helps. Diana
blue trawler wrote: My tires hold 80 psi do I set my default to 80? It came from the factory at 72.4 psi and in a short ride, three of the tire alarms went off. They were all indicating 86 to 88 psi but temp was only 64 degrees. Please respond in elementary language, as I am not a techi!
Bruce
1996 Dodge Dually, Max Brake Controller, Mor/Ryde Susp Rear Spgs, Air Bags, Tailgate Easylift,
1996/2010 Triple Slide Carriage, Mor/Ryde Susp, Kodiak Disc Brakes, Big Foot Auto Leveling System, TST TPMS
10 under and 15 over works in our case. On a very cold morning we can have an alarm for a few miles. We left in 92 temps and the third night later it was 32F
I believe my TSTs are set at 94 or 95 PSI - and in the heat of the summer day they will approach that....at that point I slow down about 5 mph for a while (around 60 mph) and they will actually drop a bit.
I tried to get Michelin to answer at what PSI above 80 do I need to be concerned for my given tires, an average 90 deg day, at 65 mph, with my trailer wt....they wouldn't.
2008 GMC Sierra C/C 2500HD D/A - w/Titan 52Gal tank
Ride Rite Airbags, Trail Air Pin Box, Garmin Nuvi 1450LMT,
Blue Ox Bed Saver, TST Tire Monitor, Yamaha EF2000is,
2009 Cedar Creek Silverback, GII, 32 WRL w/ XPS RIBS
Using the brakes can also heat up the tire inside temperature, wich the TPMS measures. But also to low used pressure for the load, heats up the tire more then it may have.
Made a spreadsheet to first calculate the needed pressure, with the formula the European tyre-makers use, then in Part 2 and 3 you can play with the temperature, to see what it does to the pressure.
Placed it in the next map on my skydrive, where you can first load it by clicking on the line , but not on the name of it, then in the right barr at download. Open after download in Excell or compatible programm to use it. 2nd from bottom , "pressurecalculationwith temp".
I would agree with Diana. I used 15% over 80 on my trip this past week, reported above, and it wasn't enough. 15% 80 psi is 92 and my tires got up to 92. I will use 20% on my way back to my home base this fall and see what happens.
I have written a note to Good Year to see what their expected pressure rise is based on a fully loaded tire that is properly inflated. They may be like Michelin, reported above, and not respond. If they do, I'll post it here.
We all know tire pressure increases with usage/tire temp, but I was surprised at the amount of the increase.
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