Announcement

Collapse
No announcement yet.

Proper tire pressure on Tow Vehicle and TPMS set up

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • Proper tire pressure on Tow Vehicle and TPMS set up

    I understand I'm asking a group of non-tire salespeople for an opinion. But a lot of you have way more miles towing that I do. While I've been pulling the 5'er for 20 years, most of the tips are less than 500 miles round trip. But end of summer we're headed on a trip that might go 3,000 so now I'm way more concerned.

    In setting up my new TST TPMS I noticed that my truck tires indicate max cold psi of 80. The door sticker on the truck indicates 55 psi for the front and 80 psi for the real (I'm assuming these are both max under the maximum tow weight?) Finally, I kept notes from the last trip to Les Schwab and their expert opinion was to run the truck tires at 50 psi for day to day driving and then increase to 60 psi on the front and 75 psi on the rear tires when towing.

    Now that I type this, I realize that Les Schwab's suggested towing psi is probably close enough to that indicated by Chevrolet's sticker. Does 60/75 seems appropriate given Chevrolet's suggested 55/80?

    Regards the TST TPMS - I bought sensors for the truck tires (I figured if I'm finally going to pay attention to tire pressure, I might as well pay attention to the truck as well.) The TST unit doesn't include a way to program different tow vehicles so I'm thinking A) set the TPMS for towing and just don't monitor when not towing (since the lower non-towing pressure will trigger all the alarms,) or B) manually change the tire pressure settings when towing and not-towing.

    My gut tells me that not monitoring when towing and leaving the settings alone is the "best" option. Less work and I've never had a blow out on the truck. And if I'm not towing it's unlikely, I'm driving very far from home. At 8 MPG I avoid driving it at all costs.

    Love to hear what you big mileage towers suggest.

    Thanks!
    Mike and Rebecca
    2022 Reflection 150 260RD, October 2021 build date.
    2001 Chev 2500 HD 8.1 liter 4x4

  • #2
    I don't think I can answer your question specifically, but I'm going to add a couple of thoughts since I have a similar truck.

    The tires on my 2019 GMC 2500 HD have a load rating of 3195 lbs at 80 psi (cold). That is the maximum load that should be put on the tire. My door sticker says to run the front tires at 60 psi, and the rear tires at 75 psi. I usually keep them close to those numbers. I have CAT scale information that tells me what the load on the front and rear axles of my TV are. I am not near the maximum of 3195 lbs per tire so I don't worry too much about my tire pressure as long as I'm close to the recommended 60 psi/75 psi. However, if I were to approach a load of 3195 lbs on the tires, I would increase the air pressure to 80 psi. (cold). (the pressure will go up as the tire gets hotter while on the road)

    I also have the TST TPMS, but I don't use it to monitor the truck tires. (yet). I rely on the factory installed system for the truck. When I know I will not be towing (i.e. winter) I usually reduce the rear to about 65 psi to make the ride less bumpy.

    If I get the TST sensors for the truck tires, I will not use it to monitor them when I am not towing. When the trailer is not connected, the TST monitor gets turned off and put away.

    Finally, just follow your usual good tire monitoring practices for a 500 mile trip 6 times, and the 3000 mile trip won't be a problem.

    I hope this helps.

    Bob
    Bob & Lynne

    2020 Imagine 2970RL
    2019 GMC Sierra 2500 Denali HD 4x4 Duramax

    Comment


    • #3
      Mike & Rebecca The tire manufacturer should have a tire weight load sheet that will show what weight it will carry at what PSI. That is where the recommended PSI from the truck manufacturer comes from. I run mine at 80 all around (my door says to run them there), but if I was not running so heavy I would work off a CAT scale and load sheet.


      Neil Citro
      2018 Reflection 28bh
      2019 F350 6.7L Long Bed Crew Cab

      Comment


      • #4
        If you don't know your actual loading numbers, run max psi in your TV tires.
        2018 Dodge 3500 6.7 Cummins w Aisin and 9 cup holders
        2021 Reflection 303RLS, Haloview RD7, Strong-arms, Micro-Air364

        Comment


        • #5
          Hi Mike,

          The label tire pressures will match the maximum axle loads on the label. As long as you are not over your axle limits, go with the label numbers . . . not the max pressure the tire can take in a different application. Be particularly cautious about taking front tire pressures above the label number . . . the 5th wheel does not add much weight to the front axle of the truck and higher front tire pressures can upset steering feel.

          I used to reduce tire pressures when not towing with the HDPP F150 because it had a pretty stiff suspension. The F350 is so soft at the unloaded end that I don’t bother doing this anymore.

          Rob
          Cate & Rob
          (with Border Collies Molly & Angel)
          2015 Reflection 303RLS
          2022 F350 Diesel CC SB SRW Lariat
          Bayham, Ontario, Canada

          Comment


          • #6
            I would keep the tires near max PSI in the rear for optimum life while towing. The front tires see very little load increase while towing. I would think the 60/75 combo would be fine. The model you have is not very heavy and if your tires are rated 80PSI then they are E rated which have a pretty substantial load capacity. I am not sure how heavy the 8.1 is, but I have to think it's less than a diesel which usually run 65psi front. I rarely change my front tire PSI. It usually stays at 65 PSI, but the Cummins is a heavy motor. The rear tires I keep about 50 non towing and 80 towing.

            For the TPMS, another option is to get 2 or 4 more sensors and program them to a lower PSI and swap sensors when you are done towing. You can program a 2nd set of tires to a different pair on the truck. For instance when towing, program the higher PSI to the outside tires on the TV (on the TPMS), and lower PSI on the inside tires. I have a sensor on my spare and it's programmed to the outside tire on the trailer so I can tell which is the spare.

            2020 GD 320G
            2021 Ram 3500 H.O. SRW.

            Comment


            • #7
              I keep my truck tires at 65 psi front and 80 psi rear, per door post figures, towing or not. Max tire load rating is at 80 psi, cold.

              I'd be concerned that 50 psi would be an under-inflated condition and lead to ruining the tires.
              Ted
              2021 Reflection 310RLS
              2020 F350 PS,CC,LB,SRW

              Comment


              • #8
                Tire pressures on the tire are max pressures. As long as your loads are under the capacity per given PSI you will be fine. For instance you run 65 in the front, which is 15 less than max that you are running in the rear.
                2020 GD 320G
                2021 Ram 3500 H.O. SRW.

                Comment


                • #9
                  the door sticker is there b/c the rear axle rating on the truck is less than the tires can carry at max load. As long as you stay with the same brand, the pressure should be about right.

                  I change my TV tire pressures not for comfort, but for traction and tire wear. Lower pressure for daily as it increases contact patch which results in more even wear across the tread pattern. Higher PSI will decrease contact patch (and rolling resistance), especially in adverse conditions (something we are seeing less of with the drought).
                  Joseph
                  Tow
                  Vehicle: 2018 GMC K2500 Denali Diesel
                  Coach: 303RLS Delivered March 5, 2021
                  South of Houston Texas

                  Comment


                  • #10
                    The tire pressure noted on the sidewall is not max pressure. It is the cold pressure for max load rating. Cold pressures and hot pressures may be higher than noted sidewall pressure.
                    Ted
                    2021 Reflection 310RLS
                    2020 F350 PS,CC,LB,SRW

                    Comment


                    • #11
                      I started paying closer attention to tire pressure on our TV and RV. We use the TST507 also, and drove approx 4100 miles in May/June (from CO to TN / AR and back). Truck tires were kept at 57 front and 79 rear (door says 60/80). So with all that, it was hot out east so the tires got really hot, but no alarms because I adjusted the high end PSI to 25% of tire pressure. Here’s what I did in prep for our trip. When you check your tire pressure, try and do so when ambient temp is ~70 degrees and of course the tires are cool AND not in the sun (one side in the sun can throw off the reading). With CO ambient temps going anywhere’s from 35 degrees to 85 degrees, the tire pressures were all over the place, but at around 70 degrees they kept the PSI I set. What I‘m ultimately saying is that I tried to stay at what the truck door said, or very close to it, and paid very close attention to when I was checking cold tire temps. I also took off the TST sensors and checked manually the PSI, which was 2 to 3 PSI off from TST. I use also tirepressure.org which has PSI and temp calculations. Just a different perspective.
                      heinz
                      Elke and Heinz
                      2018 Chevy 3500 SRW Duramax SB
                      2021 Reflection 337RLS

                      Comment

                      Working...
                      X