I know this has been discussed over and over. I just traded my 2006 F250 for a 2008. I didn't like the steel rims on the 08 and I got the dealer to let me keep the aluminum rims from my 06 and do a swap. I had BFG 315/70/17's on the 06 and when they got it to the service department, I found out about the TPMS. After some negotiation, the dealer agreed to break down all 8 tires, put the sensors on my old rims and re-mount my BFG's for free. They even gave me new bands for free. All was good until I found out that I had to have 75 psi in the tires that should have 50 psi. So I went through all this trouble to keep it "legal" and still got screwed. I emailed Ford and waiting for a response. Does anyone know if they will ever allow a tire pressure change? Is it really tamper proof? This is the biggest bunch of BS I ever heard of.

 

As far as I know the limits are set in the module,next time I get a SD on the IDS I will see if there is a programmable parameter for the TPMS pressure..

 

You should be able to set to what you want and have them retrained, they will set if the pressures are off by the set PSI. Im not 100% sure with the 08 as I havn't had any issues with one yet. Sometimes you can even adjust them to whatever pressure you want as long as they are the same PSI, you may wan't to get a cheap digital gauge to set them exact to each other.

 

The dealer or some other tire shop with the TPMS management tools ( TPMS Tools - Tire Pressure Monitoring Systems ) should be able to relearn your system for the lower pressures. For that work you should pay.

 

I just went to 37x12.50 x 20 using my stock rims, the tire shop that mounted my new tires was able to adjust the sensors down to 50 psi.

 

Went to pick up my truck today. The tech plugged into my computer and there was a setting for the tire pressure. The minimum pressure was 75psi and the max was 115psi. That doesn't help me since my new tires are 50psi max.

Here is the response I got after emailing a complaint to Ford:

Thank you for contacting the Ford Motor Company Customer Relationship Center regarding the low tire pressure indicator concern with your 2008 Ford F-250.

We would like to assist you; however, more information is needed. Please include your original message with the following additional information to allow us to proceed.

Address:
City:
State:
Zip Code:
Cellular Phone Number:
Daytime Phone Number:
Home Phone Number:
Vehicle Identification Number:
Odometer Reading:
Servicing Dealership:
Has your vehicle already been diagnosed by the dealership:
Clarification of how you would like Ford Motor Company to assist you:

 

There is no programmable parameter for TPMS. The pressure set points are stored in the ICM and the "on/off" switch (so to speak) is located in the SJB. To alter the set points it takes manual configuration (block read/write multiple parameters) of the programming and you would need to know how to convert the numbers/letters used by Ford to actual tire pressures. To actually turn it off, you have to manually configure both the ICM and SJB. There are no simple menu options to do either of these and if you do not configure either module correctly, you end up with a dead truck...

 

Is it completely tamper proof, no, but you do have to have the proper equipment (Ford Test Tools such as IDS) and knowledge of the system so you do not end up with a dead truck. Will they allow a tire pressure change, no, as it is against Federal Regulations to alter it from its factory settings...

 

75-115 PSI you have to be out of your mind, for a F-250 good luck finding a tire that will allow more than 80 PSI! You can set the tires to any number you want as long as they are the same pressure as each other, you do have to have them retrained each time you rotate your tires. If you damage a sensor or it becomes faulty for whatever reason your truck will still be able to be driven and nothing will be harmed other than the TPMS light flashing. I have had many TPMS problems and have not once had one that you had to alter the module setting, when you set your pressure you just have to relearn the system which depends on model some recheck once you go above a set MPH such as 15 or 25 MPH, some have a button that you press, read your owners manual and it will tell you. (have set some that said 35 on door placard to 45 PSI with no issue) You may not be able to turn te TPMS completely off for the 08' as theiy may have mandated it by the federal laws. And Ford probably doesnt have a clue what your talking about and is asking for more info so they can contact the dealership to look into the matter further. TPMS is fairly new to many techs and you may just be talking to someone who is new / has no clue or the service writer who usually talks out his a$$. READ YOUR OWNERS MANUAL AND YOU WILL SEE HOW IT ALL WORKS AND IT WILL SAVE A LOT OF HEADACHE.

 

I just checked the 2008 ford manual and it says nothing about a pressure spec of 75-115, it checks the pressure after exceeding 20 MPH, and rechecks every 60 seconds, set them to what you want, drive and see if it goes away it not you may have to relearn them which you will need the TPMS tool to do it.

Tire Rotation

For vehicles with different front and rear tire pressure (such as E-Series and certain F-Series), the tire pressures must be adjusted and the tire pressure sensors must be trained following a tire rotation. Refer to Tire Pressure Monitoring System (TPMS) Sensor Training in this section. Failure to train the sensors will result in a false low tire pressure event, which will cause the Tire Pressure Monitoring System (TPMS) indicator to illuminate.

For vehicles with the same tire pressure for front and rear tires, tire rotation will not affect the system.



Turn the ignition switch to the OFF position, then press and release the brake pedal.
Cycle the ignition switch from the OFF position to the RUN position 3 times, ending in the RUN position.
Press and release the brake pedal.
Turn the ignition switch to the OFF position.
Turn the ignition switch from the OFF position to the RUN position 3 times, ending in the RUN position.
The horn will sound once and the TPMS indicator will flash if the training mode has been entered successfully. If equipped, the message center will display TRAIN LF TIRE.
NOTE: It may take up to 6 seconds to activate a tire pressure sensor. During this time, the Tire Pressure Monitor Activation Tool must remain in place 180 degrees from the valve stem.

Place the Tire Pressure Monitor Activation Tool on the LF tire sidewall opposite (180 degrees) from the valve stem. Press and release the test button on the Tire Pressure Monitor Activation Tool. The horn will sound briefly to indicate that the tire pressure sensor has been recognized by the SJB. Click here to view an animated version of this procedure.

Within 2 minutes of the horn sounding, place the Tire Pressure Monitor Activation Tool on the RF tire sidewall opposite (180 degrees) from the valve stem and press and release the test button to train the RF tire pressure sensor.

NOTE: Do not wait more than 2 minutes between training each sensor or the SJB will time out and the entire procedure must be repeated.

Repeat Step 7 for the RR and LR tires.
The procedure is completed after the last tire has been trained. When the training procedure is complete, the message center (if equipped) will display TIRE TRAINING COMPLETE.
For vehicles not equipped with a message center, successful completion of the training procedure will be verified by turning the ignition switch to the OFF position without the horn sounding. If the horn sounds twice when the switch is turned to the OFF position, the training procedure was not successful.
Using the scan tool, locate the updated TPMS sensor identifiers trained to the SJB and document them on the applicable warranty claim.
NOTE: This step is required to clear DTC C2780, cause the SJB to exit the manufacturing mode and to make sure there are no other concerns with a newly programmed SJB.

If the sensors are being trained due to the installation of a new SJB, clear any DTCs and carry out the SJB On-Demand Self Test.

Tire Pressure Monitoring System (TPMS)) Pressure Sensor

The SJB monitors the air pressure in the 4 road tires with tire pressure sensors. The sensors transmit radio frequency signals to the SJB approximately every 60 seconds when the vehicle speed exceeds 32 km/h (20 mph).

The tire pressure sensors are battery operated and are mounted to metal brackets (called cradles) on the wheels inside the tires. The sensors are mounted 180 degrees from the valve stem.

The tire pressure sensor can be serviced separately from the cradle and the strap.

 

Relearning doesn't mean relearning to the new pressure. It is about learning the position and the transmitter code of the sensor itself. The only way I can see this working is the Fed changes the spec to be programmable to a set point (which doesn't defeat the purpose of the mandate) or they start making sensors that transmit a predetermined pressure to keep the light off. Since this is "new" I'm sure it will go through some learning phases. With a vehicle that has dynamic loading like a pickup truck it should be adjustable. On a car no so much, since the tire sizes can't really change nor the loading. The point is to alert the driver when they lose air, not when they lose air that someone else determined is right. I would die if I had to keep 75lbs in my tires all the time.

 

my 08 has the tpms. door sticker say 65 psi, tires are rated to go as high as 80 psi max pressure. So I am thinking that I will not have any problems so long as I don't go below 65. In reality I would think with most e-rated tires your gonna run at least that 65 psi.

I am running about 70 right now as I often have a heavy load.

 

Like senix, my '08 says 65 psi on the sticker. I can run down to about 50-55 before it triggers the low pressure light.

 

I have been doing some tests with some vehicles (2006 F-250) and set them all to 40 PSI, drove above 20MPH to see if the light would set and no light, I put one at 35 and drove to 20MPH again and light was set, sensors will not set unless one of the pressures are off by 2+ lbs.

 

Relearning is when setting the pressure, some vehicles learn when driven above 20 MPH others have a button.

Training is when you move the sensors around and have to train the SJB / Module where the sensor is located.