Tire Pressure

Manufactureres seem to be stuck in the liability world I guess. It makes zero sense to run 60/80 when you're empty. IMHO, what they should do is list 2 sets of pressures, one for empty and one for fully loaded, then interpolate for in between if needed. As it is, you wear out your tires and have a crappy ride when empty if at full pressure. And they figure regular folks aren't smart enough to interpolate or be trusted with such latitude. Ridiculous.

In the winter/empty I've been running 55/65 and I have #840 sand in the back, perfect! Better traction, better ride and better tire wear. I'll be watching my tread wear pattern carefully. If you can't tell, it really pisses me off. Tire shops are the same way, liability- go with the door sticker. Folks need to think for themselves. Or just live with a crappy ride and more tire wear when emptyo_O
 
I run pretty light with my 350 ( 6.7) so tires are 55/60 front rear
I changed the threshold with forscan. Very happy

if i tow my skid loader or 5th wheel I bump the pressure up to the factory settings.
 
I run pretty light with my 350 ( 6.7) so tires are 55/60 front rear
I changed the threshold with forscan. Very happy

if i tow my skid loader or 5th wheel I bump the pressure up to the factory settings.

What value did you use and how hard was it to change with Forscan?
 
What value did you use and how hard was it to change with Forscan?
I just changed today. Super easy. I sent front to 55psi so 0x37h (hex) in the field and rear to 60psi so 0x3Ch (again, hex value) in the appropriate field. All good.
 
I just changed today. Super easy. I sent front to 55psi so 0x37h (hex) in the field and rear to 60psi so 0x3Ch (again, hex value) in the appropriate field. All good.
One thing I should have mentioned - I went a little low to play with the tire pressures. I'm going to try 60/65 to start with but wanted to be able to go down a bit if needed.

That said - the only thing I'm concerned about is breaking a bead on cornering with low pressure. Any concern with this? I mean it is a heavy truck with a very tall sidewall so lots of pressure on the bead. At these lower rates, any concern?
 
I just changed today. Super easy. I sent front to 55psi so 0x37h (hex) in the field and rear to 60psi so 0x3Ch (again, hex value) in the appropriate field. All good.

I will do the same eventually, would you think the values will be the same on a 2021?
 
One thing I should have mentioned - I went a little low to play with the tire pressures. I'm going to try 60/65 to start with but wanted to be able to go down a bit if needed.

That said - the only thing I'm concerned about is breaking a bead on cornering with low pressure. Any concern with this? I mean it is a heavy truck with a very tall sidewall so lots of pressure on the bead. At these lower rates, any concern?
Check out this post I made if you want a bit more detail on why Ford chose the pressures they did. It also includes some other significant pressures based on use case.


TL;DR: 45 psi front and 55 rear (actual pressure) meets GAWR requirements. The rest is an FMVSS safety factor and variance for the sensor.
 
Curious if anyone succeeded in getting the dealer to lower the pressure for the light?

(The only computer I have is a work laptop which has admin restrictions on it).
 
Curious if anyone succeeded in getting the dealer to lower the pressure for the light?

(The only computer I have is a work laptop which has admin restrictions on it).

I doubt they will do it based on safety/legal concerns. You might be able to do it with a tuner, like the NGauge which does not require you to use your computer.
 
Can you take a picture of your door sticker that shows the tire pressures etc? Wondering if it's true the PSI I lower on rears and could have a lower TPMS threshold.
It is 65 front and 80 rear and its a 250..........

Also I am currently running 58 all around with the 6.7 and the tires do not appear any different then 65/80....so no worries breaking a bead......if you load up or tow....raise the pressure
 
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What value did you use and how hard was it to change with Forscan?
easy

you can put in your own numerical values with forscan I may go back and change it to 30 psi on all so I can air down off road with no idiot light
and if I get a flat it will let me know.
 
I had my rears at 66 psi cold until the fall temps started dropping. Over night the rears drop to ~63 psi and the light would come on a short while after driving. Twice after driving and the psi got over 65 psi the light turned off, however, thinking about it I believe both were highway trips so it may have been more than 20 minutes of sustained driving.

I'm in the same boat now though as I haven't put air in it and drive around with the light on. /shrug
When mine went on for going under 65 psi, it made me fill it to 80 psi before it would reset. After it reset, I lowered to 70 psi.
 
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