So here's the deal

[Hd74ica]

Have a new 2021 6.4 2500 4x4 bought with 10 miles on the clock. Get 1900 miles on the clock and a chime sounds. WTF? sez I. Low tire pressure shows on the instrument panel, I get out and look at the tires, all look normal so I drive to my local "Discount Tire" store and get a free check. Both front read 73lbs and both rear show 78lbs so now I'm confused and cycle through the dash "vehicle info" until I get to Tire pressure and the following message says "Tire pressure currently unavailable." Get home with plans to go to the dealership next day. In the morning I start her up and have the same Low tire pressure light. 2 miles down the road another chime and the light goes out and the vehicle info shows normal tire pressure. Any ideas? Thanks.

David
Michigan's thumb.

 

[MADDOG]

Sounds like a glitchy TPMS in the wheel.

 

[retired]

there is a tsb on this.

 

[Irishthreeper]

I’ve got the same truck and the first thing you need to do is lower the pressure to about 60F and 65R, as recommended. When I drove mine home it rode like a brick and the pressures were near 80 lbs.
Twice my low pressure indicator has come on and I got the same “not available” message. Tires were fine and after sitting for a bit the low indicator went out. Not sure what causes that!

 

[Hd74ica]

I’ve got the same truck and the first thing you need to do is lower the pressure to about 60F and 65R, as recommended. When I drove mine home it rode like a brick and the pressures were near 80 lbs.
Twice my low pressure indicator has come on and I got the same “not available” message. Tires were fine and after sitting for a bit the low indicator went out. Not sure what causes that!

Really 60F and 65R? My door jam says 75F and 80R.

 

[Hd74ica]

there is a tsb on this.

Thanks I'll do some research.

 

[Irishthreeper]

Really 60F and 65R? My door jam says 75F and 80R.

Maybe totally different tires. Mine shows 60/65

 

[dhay13]

Mine also shows 75/80. I have the 20" factory Firestones but did lower mine to about 65/73. Rides much better

EDIT: actually mine says 65/80.

 

[mtnrider]

Maybe totally different tires. Mine shows 60/65

Your door jamb label shows that?

.

 

[Fatbob Frank]

Maybe totally different tires. Mine shows 60/65

My 17" PW says 65Lbs too...

 

[mtnrider]

My 17" PW says 65Lbs too...

Power wagon will be different then a regular 2500/3500. Doesn't have the load carrying capability rating.

.

 

[Irishthreeper]

Your door jamb label shows that?

.

Yep. I’ve got Firestone Transforce LT275/70R18’s. Calls for 60/65 cold

 

[68PowerWagon]

Really 60F and 65R? My door jam says 75F and 80R.

I run my 4th gen at 55-60lbs. Rides much better. When I am pulling the 5th wheel I bump it up just a bit but I probably don't need to as there is no tire bulge at all. No tread wear problems either. I got 35k out of the Firestones & will get 45-50k out of the Coopers I now have on it.

 

[huntergreen]

Always thought the rear tire pressure should be lower than the front when running empty.

 

[retired]

Always thought the rear tire pressure should be lower than the front when running empty.

unless you like your fillings jarred loose ..makes no sense to run high psi in back when empty to me. I bet if people weighed their trucks empty they would be surprised how little weight the rear tires need to support.

 

[dhay13]

unless you like your fillings jarred loose ..makes no sense to run high psi in back when empty to me. I bet if people weighed their trucks empty they would be surprised how little weight the rear tires need to support.

Ask and ye shall receive. This was mine this spring with an almost full tank of fuel and me in it. My 2.5" solid hitch insert was in too. It probably weighs about 30-40lbs

 

[Wycheguy]

It always amazes me how people are still going off what the door sticker says. Doesn't anyone remember the Firestone tire debacle from the late 90's? While both sides, Firestone and Ford, did blame each other it was noted that people kept their tires inflated by the door sticker and not the recommended values on the tire. It could have been a bad tire design too but I seem to remember that the sticker PSI value was a contributing factor.
Personally, I don't care what the door sticker says, the tire was manufactured for a maximum PSI and I step down 5 PSI and run them there.

 

[Wycheguy]

Regarding the original post, I also had the TPMS ding at me 2,000 miles in. I checked all pressures, which they were within range, and ignored the light. It went away 2 days later and hasn't come back. Although now after writing this I fully expect to go out today and have it ding at me......

 

[retired]

Ask and ye shall receive. This was mine this spring with an almost full tank of fuel and me in it. My 2.5" solid hitch insert was in too. It probably weighs about 30-40lbs

View attachment 476184

yup, each rear only needs to support 1600lbs so no need to be running max psi which supports over 6000lbs for the pair of rear tires.

StackPath

 

[JRs 17 Ram]

I did the chalk line to find my ultimate pressure. Then used the Alfa OBD app to reset the tpms alarm settings. This was on a ‘17 2500.