Hi,

My wifes truck is ready for a set of tires, so I just ordered a set of new tires for her from Tread Depot. She uses this truck for work and it is running around at max payload all the time.

You can see the truck here:

https://www.f150forum.com/f38/our-ec...review-208509/


My question is, will I need to have the TPMS system re-calibrated to accomidate the higher pressure of the load E tires?

It is a 2012 FX4


Thanks

 

Hi Stinton,

Just replaced the P rated tires on my 2009 F150 with E rated LT tires about a month ago. As far as I know the TPMS only comes into play when pressure gets too low. Discount tire replaced my tires and TPMS works fine with the new tires.

 

I have a 2013 F150 4x4 SuperCrew with the HD Payload pkg. which has the E rated tires. Door sticker says 55 psi front/60 psi rear. The TPMS doesn't come on until the pressure is about 30 psi. I tried it, lowering the pressure 5 psi at a time.

On other vehicles I have had the TPMS would activate when about 6-8 psi low. I don't think Ford uses a different TPMS stem in the trucks with the E rated tires. If your wife is running at 80 psi it will be a long time till her TPMS warns you that a tire is low.

 

As far as I know, Ford's TPMS only warns for a low tire, somewhere around 30-35 psi. If you want to set it to a higher psi, a ford tech might be able to but I know for sure you can set it for whatever value with a SCT tuner.

 

something to keep in mind, max payload does not necessarily mean that you should be running the tires at 80psi. The higher the pressure the more they can carry but unless you have a maxtow/hd payload with the 4800lb RAWR, chances are 60psi in a load range E tire is rated for more than the axle already so the extra 20psi will just make the ride worse and cause the tires to wear faster down the middle.

 

Yes, I do not plan on running these at 80psi, but it will be higher than the max pressure of 44 psi on the stock P tires.


Thanks for everyones input.

 

I would run at 60PSI and ensure you have high pressure valve stems used

 

I replaced my Pirelli P's, which were supposed to run at 35psi, with LT's that Michelin tells me to run at 48psi (to meet or exceed the Pirelli's weight rating).

Normal driving, the TPMS seems to work fine.

But when towing all day, I'll often get a TPMS Fault message after a few hours. Since I changed the rims as well as the tires, I could just have a wonky sensor in one of the new rims.

But maybe you have to inform the truck's computer what tires you are running? I've heard that somewhere in there you can specify size and maybe type? Next time I take it in I'll ask.

 

Interesting, I have not towed more than an hour at a time since I got my tires (I have mine at 50psi) but I will be this weekend. I'll have to keep an eye on it.

 

Go by the load/inflation table for the new tires. DO NOT pump up the new tires to higher weight capacity than is on the sidewall of the stock tires. Here is the load inflation table for size LT275/65R18E mounted on single wheels (not duals):

LT275/65R18 Single
Max
Wt...@PSI
-----
1940 ..35 PSI
2130.. 40
2310.. 45
2535.. 50 (max for load range C)
2660.. 55
2825 ..60
3000.. 65 (max for load range D)
3150.. 70
3305.. 75
3415.. 80 (max for load range E)

Probably about 50 PSI is the max you want in the LT tires. That will give you 5,070 pounds of weight capacity on the rear axle, which is probably more than your rear gross axle weight rating (rGAWR). Higher PSI will gain you nothing but a stiffer ride and faster wear on the center of the tire tread.

Note that some brands of tires have a LT275/65R18C tire (load range C with max 50 PSI). Those will give you all the weight capacity you need. Here's one:
http://www.tirerack.com/tires/tires.jsp?tireMake=Bridgestone&tireModel=Dueler+A% 2FT+D695&partnum=765SR8D695OWL&vehicleSearch=false &fromCompare1=yes&tab=Specs