Tire pressure on other than stock tires.

[tw205]

As I’ve yet to find much in the way of info on tire pressure when running larger tires, what do y’all run on yours. I’ve replaced the 205/75/15 stocks with 31 1050s. They are general grabber ATXs. Great in the snow and sloop up here. My door says 30 lbs pressure but she rides a bit hard. Stiff sidewalls. Any opinions out there?

 

[dvdswan]

What load range are the tires? If they're load range "E" then you're just going to have a rough ride no matter what the tire pressure.

 

[tw205]

What load range are the tires? If they're load range "E" then you're just going to have a rough ride no matter what the tire pressure.

Load range C. Just a little BII. Good lord I couldn’t imagine Es on it. Been running 30lbs per the door sticker. Gonna drop down a few pounds and go jump the tracks. See if it helps.

 

[Uncle Gump]

I did the entire contact patch thing when I put the new tires on my truck. They are E-rated and I was worried about the ride. The ride overall is better then I thought I could get... but I ended up with 29 psi front and less then that rear( I don't remember exactly). I did stagger the pressure in the beginning... now I just run them all at 29.

EDIT... It's hard to find 16 inch truck tires that aren't E-rated.

 

[dvdswan]

You should be good with 30 psi. It could be you were used to the old tires or they were (dare I say) car tires with softer side walls.

 

[tw205]

Actually the last tires where super swampers . Talk about a hard riding tire. Good for the mud but that’s about it.

 

[09fx4guy]

EDIT... It's hard to find 16 inch truck tires that aren't E-rated.

I remember how much time I spent looking for a set of 265/70R16 tires (much, much more than the average person should). Choices are so limited for anything other than a E load. I had wanted to get a set of BFG All Terrains, but I ended up with a set of General Grabber AT2's. They are a pretty good tire. They came out with that AT/X not longer after I brought my tires.


OP- you will probably have to play around a little bit. I know I tried mine at the door rated psi (30 I think), then went up as high as 38 and as low as 28. The sweet spot for me was about 33 front and 32 rear. Don't be afraid to go up a little bit, just don't go too close to the sidewall max rating.

Some C load tires may be a bit much on a B2. Next time, you can also compare tire weight, as the additional weight will also add a little bit to the ride harshness.

 

[sgtsandman]

If you can find the load rating for the original tires, divide that by the max pressure to get the supported pounds per square inch.

Take that number and multiply it by the recommended pressure for the original tires. That will give you the target load capacity for each tire.

Take the new tire and do the same thing as the first step to get the supported pounds for 1 psi on them.

Play with the inflation numbers to match the OEM load rating as close as you can.

My original tires on the 2011 needed 35 psi. After doing the above, I came up with 36 psi to get close to that. I think it is slightly over.

 

[RonD]

In my opinion tire pressure is a personal choice
Tire makers have their opinion for best wear and longevity, but they are not the ones driving the vehicle
Ford also has their opinion on the stock tires, but once the vehicle is sold they are no longer in charge, you are

Tires are the first line of defense for bumps, springs are the 2nd, wrong shocks are the 3rd
Shocks do not support the vehicle, they are there to dampen spring deflection and recoil, that's all, if you put "stiff" shocks on, the springs can't do their job, absorb wheel up and down movement without passing it on to the frame/body
With both shocks disconnected on an axle you should be able to move(bounce) the body/frame up and down easily, but it keeps bouncing because there are no shocks
With shocks added should be just as easy to bounce but won't keep bouncing
If its way harder to bounce then wrong shocks for smooth ride

If its "stiff" with no shocks then its "over-sprung", the spring's weight rating is too high for the weight of the vehicle on that axle, this is a common issue for the rear axle on pickup trucks because they have springs rated to carry 1/2 ton(1,000lbs) more than their empty bed weight, this can be corrected with lower weight rated springs and then an overload spring added, but costs more so car makers don't do that in most cases

Nothing can correct "over-sprung" vehicles except changing the springs or adding more weight to body/frame so spring rating is correct for the weight on that axle

If shocks and springs are OK, then you can set tire pressure for your preference and driving conditions
If your roads have lots of "bumps" you may want the tires to be lower pressure so they absorbs the smaller "imperfections" in the road surfaces, lol
The lower pressure can effect tire wear so you need to keep an eye on that and use your best judgement
Lower pressure also means better traction, and traction is friction, and friction is tire wear, lol, and friction also effects MPG, lowers it a bit, but just a bit

 

[gaz]

tw205,

I have experimented with different tire pressures over the years, my goal may be different from your. I demand 2 specific results:

1) the longest tire life possible
2) highest possible fuel economy

In all my mid sized trucks and any sized cars, 32psi has been and continues to work the best. If the ride quality on the street is undesirable, I look to amending the suspension.

My 3rd, condition is the result of the first 2 being maximized, traction. Traction is maximized by the suspension but with 32psi, the tires have proven more consistent feeling while driving.