What psi do ya'll run in the tires?

[rammertide07]

Just curious what ya'll run in ya'lls tires. I went to wally world the other day for an oil change....they went ahead and put 70 pounds of air in all of my tires....they only call for 50. I know some people run more air in the front vs back. I was looking at my VIN sticker on the door and it said my rear vehicle weight was more than my front. Thats not what I expected with the engine being in the front. I'm fixing to put about 1200-1400 miles (unloaded) on my truck in the next 5 days and I want to make sure that I have the "right" pressure in them. Thanks fellas...

 

[BIG JOE]

JMO but it depends on the Tire construction.. # of ply's and so on.

I always go with what manufacturer sez, on the tire itself.. + - a few pounds, depending on the Load.

On my GoodYear 235/85/16, G647's (E rated, 10 ply's) Loaded & Empty, I run 60 in the backs, 70 in the fronts. Year 'round.

Joe

(2WD, DRW)

On Edit: The best thing to do is.. Get yer truck weighed, get a front and rear axle weight, empty & loaded.. go to the manufacturers chart for PSI per (divided by 2, or 4) axle weight. (make any sence ?) Those will be No S**T numbers to PSI from.

FWIW ? I used local CAT scale.

 

[rammertide07]

JMO but it depends on the Tire construction.. # of ply's and so on.

I always go with what manufacturer sez, on the tire itself.. + - a few pounds, depending on the Load.

On my GoodYear 235/85/16, G647's (E rated, 10 ply's) Loaded & Empty, I run 60 in the backs, 70 in the fronts. Year 'round.

Joe

(2WD, DRW)

On Edit: The best thing to do is.. Get yer truck weighed, get a front and rear axle weight, empty & loaded.. go to the manufacturers chart for PSI per (divided by 2, or 4) axle weight. (make any sence ?) Those will be No S**T numbers to PSI from.

FWIW ? I used local CAT scale.

My tires are 8 ply. Can I not go by the VIN sticker on the door? It has a place for the rear weight and front weight.

What does your tires say on the side-wall for the psi rating?

 

[dpantazis]

google chalk test for tires. better yet, search here.

if you have 8 ply tire, you are SERIOUSLY under rated (OVERWEIGHT!) and you pull a 5th wheel?

 

[BIG JOE]

My tires are 8 ply. Can I not go by the VIN sticker on the door? It has a place for the rear weight and front weight.

*You can.. as a reference... but (IMO) those PSI numbers are for the OEM tires that came on yer truck ... New. Prolly 215 or 235, Firestone's.

What does your tires say on the side-wall for the psi rating?

**80 psi for the MAX load. For these [specific] Tires.. not the MAX GVWR of an F-350, DRW, and that's where the math comes in.. with a Known.. Axle weight, in relation to the Brand Specific tire, and It's [needed] PSI, for that Known weight.

If a tire says X? psi Max.. that doesn't mean you Have To.. run X? in it.

JLDickmon is a "Tire Guy".. maybe he'll jump in here for ya too ??

 

[BIG JOE]

google chalk test for tires. Better yet, search here.

If you have 8 ply tire, you are seriously under rated (overweight!) and you pull a 5th wheel?

x2 on the 8 ply's

And Yes... dp's Chalk method is a VERY good way of getting to proper PSI.. specific to Your truck.. and it's load(s)

 

[rammertide07]

Side wall says 50 psi cold. So with the outside temp being in the 90's.....???

Load index for the tires is 3197lbs. If that is per tire then thats a total of 12,788lbs spread out across all the tires...if that is a correct method. I can understand possibly being underated when pulling my 5th wheel. I just dont know how much more weight is being put down on my bed. I've only pulled it once....75mph for 4hrs.

Any suggestions on 10ply A/T's?

 

[AK Rover]

I run 285/70R17 D-range tires at 65 psi. That is the max listed on the sidewall and gives a trade off of traction to fuel mileage.

The larger tires will have higher weight capacity despite the lower load range rating. You shouldn't exceed the max psi listed on the sidewall. The idiots at walmart looked at a chart that said your truck should have a certain size and load range tire and that it gets inflate to 70 psi. They aren't smart enough to read the sidewall and realize they overinflated your tires.

At very minimum you should be running a D-load range tire, but since you tow a fifth wheel E-range would be better. Even though your current tires have the same load capacity as the factory E-rated tires their construction isn't designed for the heavy loads. A C-rated tire like you have is best suited for 1/2 ton trucks and SUVs that don't carry the heavy loads our trucks are designed for.

 

[rammertide07]

Where do you get that chalk at?

 

[BIG JOE]

Any Snap Line chalk works well