Tire pressure sensor question.

[Ernie Scar]

I've been told that if you have a tire pressure fault (not running factory rims)your timing is retarded. Can anybody confirm this or is this a load of crap?

[Pahrump]

I've been told that if you have a tire pressure fault (not running factory rims)your timing is retarded. Can anybody confirm this or is this a load of crap?

Never heard that...and it did not seem to hurt my truck...if theres more there after I can turn off the TPMS fault then HELL YEAH lets giterdone

[DIESEL FOOL]

Put all four sensors in the spare, pump up to 80PSI, relearn the thruck. It works as I did it today. Then you don't have to be worried about being retarded. lol

[Stroken]

I wish I would have know this before spending the money on 24" bands and installing them in my tires. Know the only way to keep the light off is to run 80 pounds in the 38"X24" Kuhmos..... it sucks

[sporacer1]

I wish I would have know this before spending the money on 24" bands and installing them in my tires. Know the only way to keep the light off is to run 80 pounds in the 38"X24" Kuhmos..... it sucks

You can run 65 psi min in all 4 tires. Just relearn them after setting the air pressure. I have been running this way since new and no light.

[Pahrump]

Even 65 is too high for the 38 Kumhos...mine are rated at 55psi

[DIESEL FOOL]

I don't have to worry about them any more. Yahoo.

[bkuepaint]

I am running 37" tires with 22" tires. I've been running my tires at 55PSI and I have no problems unless my PSI drops below 50, then I get the Low Tire Pressure warning

[Pahrump]

Mine sets the fault at below 65psi...when I had my 37's they were rated for 65 I ran 68 and everything was cool

[DIESEL FOOL]

Yes but the F350's use 80psi sensors and air pressure in the rear only to attain payload ratings from the factory. F250's run 65psi sensor all around.

[Ernie Scar]

Diesel Fool did the sensor in the spare trick like you said and it worked great until I drove a while on the highway and tire pressure fault returned. If the truck is parked for awhile and driven around town there is no fault. Have you experienced this or am I missing something?

[BigIslandBoy]

Mine sets the fault at below 65psi...when I had my 37's they were rated for 65 I ran 68 and everything was cool

At 65psi in the rear of my 350 my light would come on. I pumped it up to 70 and it when off. I'm going to let out1psi at a time to to see where it will set the light off. Is it bad to to have a few psi more than the tire is rated for? My 35's are rated for 65psi.

[sporacer1]

At 65psi in the rear of my 350 my light would come on. I pumped it up to 70 and it when off. I'm going to let out1psi at a time to to see where it will set the light off. Is it bad to to have a few psi more than the tire is rated for? My 35's are rated for 65psi.

The reason your light is on is because your tire pressure gauge may be saying its 65 but the sensors are reading less pressure. The way to set tire pressure is with the vehicle cold and not in the sun.
Tire pressures increase and decrease with outside temp's, sun beating on them, and driving hard in the corners will raise temps.
The pressures will increase as much as 5-15 degrees due to heat build up. The moisture in the compressed air causes this. Thats why race cars use either a air dryer or nitrogen to pressurize tires. Even then there is still a buildup.

[bkuepaint]

I never thought of putting the sensors in the spare. GOOD IDEA!! I think on my next set of 37" tires I will have them put the TPMS sensors in the spare and set my tires at 55psi for a better ride.

[DIESEL FOOL]

I have had the warning come on sporadically but very far in between. It also goes away by itself after the truck sits turned off. Mine seems to only do it if I go over rough road. I have my spare aired up to 80psi because I have an F350. I am going to pump it up to 90psi as it is getting colder here and see what happens. It is a little irritating but is alot better than always being on. I think it may have something to do with how close all the sensors are. It works good enough for me until they figure out how to turn off the sensor system with the DashDaq.

[battlecattle]

couldnt you just get 4 pipes put a sensor in each and pressurize them at each wheel to Xpsi then never worry about it and just check your pressure like a normal before these fangled computer things:p

-Josh

[DIESEL FOOL]

I tried the plastic pipe method and it worked even better than the spare tire method until the plastic gives out. I am not sure if they can transmit through metal or not, otherwise I would make some tubes out of exhaust tubing. i was using black ABS plumbing pipe. The glue would hold but the plastic simply gives up at 90psi.

[sporacer1]

I tried the plastic pipe method and it worked even better than the spare tire method until the plastic gives out. I am not sure if they can transmit through metal or not, otherwise I would make some tubes out of exhaust tubing. i was using black ABS plumbing pipe. The glue would hold but the plastic simply gives up at 90psi.


Dont waste your time with this method. The sensors need to rotate because they will stay in the sleep mode. Here is a note from the ford service manual.

NOTE: The TPMS sensors do not transmit when the vehicle is stationary. If the vehicle has been stationary for more than 30 minutes, it will be necessary to wake up the sensors so they will transmit the latest tire pressure information to the SJB.

[Pahrump]

So then theres no way in hell they are working in the spare....

[Ernie Scar]

I figured it had something to do with sensor rotation. So no the tire in the spare trick doesn't work. It only works for about 30 minutes until the system "wakes up". Would it be possible to use a sensor from a 150 or is the sysrem only calibrated for what the truck came with?

[sporacer1]

I figured it had something to do with sensor rotation. So no the tire in the spare trick doesn't work. It only works for about 30 minutes until the system "wakes up". Would it be possible to use a sensor from a 150 or is the sysrem only calibrated for what the truck came with?


The trucks SJB(Smart Junction Box) recieves the pressure readings from each wheel. The parameters are loaded into the sjb by the factory.

[DIESEL FOOL]

Think what you want about the spare tire method, but mine is working more than 30 minutes. Since I put mine in the spare, I have seen the warning twice but only temporary. After a rough road or something like I said perviously. It has been two weeks since the last time, and I am pretty sure my spare is not rotating.

[sporacer1]

Think what you want about the spare tire method, but mine is working more than 30 minutes. Since I put mine in the spare, I have seen the warning twice but only temporary. After a rough road or something like I said perviously. It has been two weeks since the last time, and I am pretty sure my spare is not rotating.

I am stating facts straight out of the ford service manual.

NOTE: The TPMS sensors do not transmit when the vehicle is stationary. If the vehicle has been stationary for more than 30 minutes, it will be necessary to wake up the sensors so they will transmit the latest tire pressure information to the SJB.

[brad g]

Im running 35 12.5 20 toyo Mts and im running them at 52 psi no problems truck came with stock tires set at 70psi all around I just put my new tires on pumped them upto 55 front 52 in the back took it for a ride to wake the sensors up then I set the sensors ..... no problems at all .. the low tire light should only come on if one of the 4 or 6 tires( duallys ) is 10 psi below the others...

[versitek]

I am stating facts straight out of the ford service manual.

NOTE: The TPMS sensors do not transmit when the vehicle is stationary. If the vehicle has been stationary for more than 30 minutes, it will be necessary to wake up the sensors so they will transmit the latest tire pressure information to the SJB.

So then wouldn't it work to leave the sensors at home! They would never wake up and trip the light?

[sporacer1]

So then wouldn't it work to leave the sensors at home! They would never wake up and trip the light?

The SJB needs to see the sensors. It will throw the light on.

[DIESEL FOOL]

My spare method is still working just fine since last post. Matt is close to releasing a proper fix. :)