I took my first long trip pulling my boat after installing Ford’s Trailer TPMS Kit. This was the TPMS kit only (no camera). I had to have a tire shop install the sensors. After that, the install and setup was easy. The attached pictures are the pressure and temperature readings just after exiting the interstate, where I had the cruise set at 72 MPH. The outside temperature was about 85 degrees. I keep my tires set at the max of 65 PSI. It’s my understanding pressure and temperature is dependent on outside temperature, as well as other factors. So, I’m assuming these reading are nothing to be concerned about. I’m curious why the right front tire consistency ran a bit hotter than the rest. So far, I’m pretty impressed with the system. I question Ford’s use of sensors that say they’re not compatible with steel belted tires. Is there a trailer tire that doesn’t have some steel in it? Maybe the more you have, the larger the risk of interference.


Does anyone know what the default is that will trigger a low PSI warning? I can run a test to figure this one out. I suspect it’s the standard 25%.

Does anyone know if there is a built in high temperature trigger? I would rather not figure this one out. I guess if a tire is losing pressure it is heating up at the same time, so maybe this would be redundant. Would there be a situation where a tire is getting too hot, but not losing pressure?

 

Do you have a part number handy for the kit you used? I need to add a set to a boat trailer as well. Thanks.

 

I think this is it, but I would double check with your parts department. I chose this option as part of my truck order, so it was just shipped with the truck. The box doesn’t have a part number on it. I believe you have to have Ultimate Trailer Tow for this to work. It was $500 when I bought it. It’s invaluable in my opinion if it gives me advanced notice that I have a tire going flat, before it starts to shred and damage the boat and/or fender.

 

thanks! I too have the ultimate trailer towing package and also bought the camera and tpms kit. The kit did nit arrive with the truck and the set that comes with it will be for an RV.

 

I stand corrected. The part # was on the box.

 

I am curious as to what they measure cold. You stated 65 but the second pic shows 73. I assume the first one is while towing, but I have never seen mine go that high and I tow in 100+ degree temps. What were you towing? How heavy was it?

 

If I understand you correctly, the sensors measure correctly when cold (65 PSI). They climbed to 73 PSI once rolling at highway speeds. I didn’t think to check what the the cold temperature was. Wouldn’t it just be ambient temperature? I’m towing a 8000 pound boat.

 

I see where my confusion is. Your second pic was towing so those are normal PSI. The first one was temp, which my 17 and 21 didnt have. I havent tried the 22 yet.

 

So the TPMS kit requires the sensors to be installed inside the tire? If so, I wasted $500+. I have a TST and thought these were screw on's and would save me a gadget in the cab. I'm not thrilled about the prospect of hauling the camper to a tire place.

 

Yes, they are internal. They replace your current valve stem. Tire shop charged me $75. They look like this.

 

2022+ have pressure and temperature
2017-2021 have pressure only.

My tire temps are similar to OP. However my tire pressures are 80 psi cold and run in the low 90's once up to operating speed on a hot day in the summer months.

This system is invaluable and worth the $500 for the peace of mind. Just more information at your finger tips....

 

I removed the tires and took them to the tire store. Easy peasy. I replaced my TST with these.

 

There can be a few reasons for an outlier tire PSI/temperature.
1. Bearing problem
2. Dragging brake
3. Failing tire
4. Bent rim - I had this exact issue and that wheel/tire was always about 5 PSI above the other three tires.
5. Sunny side
6. Alignment

 

Great list, but add to that an outlier sensor.

Other than buying a heat sensing gun, the easiest way to rule that sensor out is to move that tire to an alternate location and that will tell you if it is just the sensor, or if you need to run down the 6 other potential causes. Until you change your dash setup that tire in its new location will still report as front right. If it is no longer reporting hot, but another one is now reporting hot your problem is not the sensor.

My guess is sensors have a +/-3% range specification, so at 110 psi about 3 degrees would be “normal” discrepancy in reading accuracy, so 107 to 113. If spec is +/-2% that is about 2 degrees. If 2%, then range at 110 would be 108 to 112.