looking to put larger tires on by 2019 f-450 to get rid of the skate board look., thinking about these 255/70r22.5's which are 37" in diameter. would be interested in other options.

https://buytruckwheels.com/collectio...h-m647-mix-use

 

Not that the current crop of OEM Ford factory aluminum dual wheels are any better, or any more "American", but what is the vetting process for verifying the mechanical integrity of wheels from an importer who advertises "American-Located" by virtue of a sales distribution center just a semi truck ride away from the shipping port in Long Beach... that lacks the vetting process to verify the correctness of the syntax used in the language of the foreign market they are trying to reach, never mind claim origination from, on the home page of their website?

 

 

Try Dually Wheels - American Force Wheels - Fuel Off-Road Truck Wheels - Free Shipping, they have 20's, 22's, 24's and 22.5's.

 

also is the problem of " American distributor" who has a "vetting" process published but in reality the process is based on a bell curve in that 25% will have a problem within warranty, 50% will never have a problem, and 25% will have a problem after warranty.....while at the same time sourcing the merchandise from the same imported source, changing the label, marketing up the price 40%.

 

My 2020 F450 converted to super single
2.5” lift with 42” Continental MPT 81
work done by DBL Design

 

Truck looks sweet, but honestly I've always wondered what the purpose of Super Singles are? Wouldn't you lose a ton of payload/towing capacity when you lose the dual tires?

 

let me attempt to splain, can you air down 19.5” commercial tires and drive on sand ?
Continental MPT81 are rated at 6779 lbs....

 

Good question, unfortunately, I'm not an expert on tires, or driving on sand. It was a simple question... forums are a place to ask questions if you have them.

 

It is a good question. And a simple one. And the rhetorical question offered as an answer might not adequately "splain" the answer to anyone who isn't already familiar with some key characteristics of 19.5" wheels and tires.

19.5" tires and wheels, and in fact any ".5" tire and wheel, are mated with a significantly shallower bead taper than evenly sized tire and wheels, which have a bead taper that is 3 times steeper of an angle. The shallow bead taper of a "half size" tire and wheel assembly provides all the more reason to follow the manufacturer's directives for properly matching tire width to wheel width, in accordance with well researched and field proven industry standards. Fortunately, these standards exist, because while we can easily see how tires and wheels fit up when the truck is standing still, it is a lot more difficult to evaluate the stresses acting against tire retention and sidewall distention when the truck is fully loaded and careening around an off ramp cloverleaf, or clawing through sand.

While it is a common practice to "air down" tires to allow the tire to distort into a wider footprint, increasing the contact patch size over deep and soft sand to avoid the tire "digging in", it is ill advised to "air down" 19.5" tires to enhance traction in deep sand because unlike whole size rims for tires having a steep 5 degree bead taper, half size rims tires have a shallower 15 degree bead taper that makes it easier to mount the much stiffer sidewalls of 19.5 tires onto the rim. Easy on, easy off. That shallow bead taper means that 19.5" tires are more likely to walk off the rim when underinflated and rolled under load at the same time.

But a far more important reason not to air down 19.5 truck tires is because of what makes the sidewalls so stiff... the steel cord(s) in the sidewalls. Under inflation of a steel corded sidewall tire, combined with rotating the underinflated steel corded sidewall tire, is like taking a metal soda can and bending it back and forth rapidly. Eventually, the metal will fatigue at the bend, and the two halves of the can will tear and separate.

The thin steel strands that make up the steel cord in the sidewall of 19.5 tires can fatigue in much the same way when insufficiently supported by adequate air pressure. The underinflated tire rotating from loaded radius to unloaded radius 650 times a minute (at 60 mph) is the same thing as rapidly bending the coke can back and forth. The steel cord may not tear from that alone... but when the tire is reinflated back up to the proper pressure to meet the load rating, the metal fatigue in the sidewall cord caused by the continual flexion can spontaneously give way to a zipper failure.

The difference here is that 16", 17", 18" and 20" truck tires generally do not have steel sidewalls. The steel cords in these whole size tires are limited to just the tread belts. Military tires and wheels are often equipped with bead locks.

With 19.5" tires, one not only needs to be aware of the maximum inflation pressures... which are quite high at between 90 to 110 psi, depending on load rating... but one also has to be aware of maintaining MINIMUM inflation pressures, which can be as high as 70 psi, and usually never lower than 65 psi, again, depending on the specific tire model and load rating. The consequences of running a 19.5 tire underinflated below the minimum inflation pressure can be injurious. Even deadly. Once a 19.5 tire with a metal fatigued sidewall is reinflated to the tire's normal operating pressure range again, a sudden, catastrophic zipper failure can occur in an instantaneous burst, maiming or killing all in it's immediate vicinity. There are videos on YouTube of these incidents.

Ford began putting big labels on all chassis cabs recommending that operators use a 6 foot long extension on any inflator for 19.5 tires. The Tire Industry Safety Council and the Rubber Manufacturers Association strongly suggest that tire shops use an inflation cage when dealing with 19.5 tires, since it is not possible to know if a customer has run their steel sidewall truck tire in an underinflated condition previously... (like trying to air down for more traction in sand, for example).

 

Love it when someone who knows what they are talking about can give a clear, simple explanation for those of us that are here to learn. Thanks @Y2KW57!

 

Interesting... thank you very much, Y2KW57. Wasn't aware they put steel cords in ".5" size tires, very informative. Would this cause a large loss of payload when you go to singles, since you're essentially going from a DRW to a SRW?

 

it will depend on the specific tire, but generally no it won’t limit payload.

The OEM duals are rated at 3,750 lbs each in Dual configuration, so a combined 15,000 on the rear axle. F450 pickup rear axle max is 9,900 lbs, so the tires are not a limiting factor.

The MPT81’s mentioned in this thread have a rating of 6,779 lbs in a Single configuration, which is 13,558 lbs combined. Still well over the 9,900 lb axle rating for the rear.

Of course, those MPT81s also have a max speed of 66 MPH, so all the F450 speed demons would not be happy.....

 

Agreed... I know a fellow truck camper owner that's running them on a converted F-450!

 

The wheels in the original post are f-450/f-550 wheels

16 ply tires rated at 5500lbs each at 120psi.

6 tires will give you a gvwr of 33000 lbs. my truck is only 14000 lbs gvwr. And a stripped down f-550 is 19000 gvwr.

the mixed use tire has the deepest threads.

i gave myself a week cool off period before pulling the trigger and so far...haven’t heard anything that would be a show stopper.

the real only concern I have is that they band 3 per pallet and they seriously believe that the carrier will not stack them.

i had a $5k shed delivered to me that came on two pallets that said do not stack and they were stacked when they pulled up to the house.

The wheels don’t come boxed, just Reynolds wrapped, banded, and stacked on a pallet.