Tire question
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Tire question
I have a 2008 F450 and I put a set of american force 22.5 wheels on. The tires are 255/70/22.5. They are a 16 ply tire so I realize they ride like crap and the chance of a good ride is slim. The tire pressure on the tire is 120psi. My question is do any of you guys have a set up like this and if so what pressure are you running to get a good ride. Also what did you do to balance the set. It is a very hard riding tire and I want to get the best ride I can out of them. And I know what Im asking about the ride being good, which is close to impossible with this set up. However I was just wondering if any guys had the set up and what kind of ride they got and how they were running the set up.
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From: Wayyy NoCal, USA
With how much load?
More specifically, what does the truck weigh and what are you normally carrying?
The 120 psi is MAX pressure, which you need if you are loading to the maximum capacity of the tire. Which I suspect you will rarely be doing! So you can run a LOT less.
The tire manufacturer may have charts for how much pressure is required for a given load. Did you check their web site?
More specifically, what does the truck weigh and what are you normally carrying?
The 120 psi is MAX pressure, which you need if you are loading to the maximum capacity of the tire. Which I suspect you will rarely be doing! So you can run a LOT less.
The tire manufacturer may have charts for how much pressure is required for a given load. Did you check their web site?
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From: CA Bay Area
I do have 22.5 wheels on my motorhome, but motorhome is 30,000 lb alone.
You definitely have too much pressure in those tires. Even in my motorhome I pump 90 psi.
Go to tire manufacturer site and find the recommended pressure for your load, or rule of thumb is to pump the same % of the max pressure what is the % of max load you are putting on it.
You definitely have too much pressure in those tires. Even in my motorhome I pump 90 psi.
Go to tire manufacturer site and find the recommended pressure for your load, or rule of thumb is to pump the same % of the max pressure what is the % of max load you are putting on it.
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I checked the manuf. website. It doesnt have anything with the loades and psi. Just shows the max psi. Max is 120. I just took someair out and now they are at 90psi. I will have to drive it in the morning to see if there is a difference. When I talked to American Force they said they put 60psi in them. Which seems low to me but hey what do I know.
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From: SE Wyoming
Our F450 runs out pretty much like yours, weighs just under 11K and tow up to 20K, we run the Ford spec which IIRC is 90-95 in the rears and 105 in the fronts. Door jamb sticker will say for sure. I think the suspension is the biggest problem with the harsh ride, even with 3 tons on the back the truck barely squats.
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You are right about the truck and loads. Its crazy what the truck will tow. But not sure if the chart in the door jamb would be correct since the tires are no where near the factory size.
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Postmaster
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From: CA Bay Area
I checked the manuf. website. It doesnt have anything with the loades and psi. Just shows the max psi. Max is 120. I just took someair out and now they are at 90psi. I will have to drive it in the morning to see if there is a difference. When I talked to American Force they said they put 60psi in them. Which seems low to me but hey what do I know.
Years ago I did own 7 tons motorhome that was riding on narrow tires inflated to 90 psi. Those things have been dancing all over the road all the time. At the time there was a small business advertising wider rims for front axle of those motorhomes. I spend small fortune for those wheels and wider tires that would carry the load at 50 psi. The ride comparison was day and night.
One thing that softened ride of my F450 were suspension helping bags.
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From: CA Bay Area
Is this dually? Assuming your rear axle is 5000 lb, that makes 1250 lb per tire.
1250/5070= 0.246
Now you multiply 0.246 by 120 max pressure to come to about 30 psi pressure.
Most of the manufacturers also list min pressure what mostly is 50% of max pressure, so I would not go below 60 psi, but wait, isn't 60 what the other guys are pumping?
1250/5070= 0.246
Now you multiply 0.246 by 120 max pressure to come to about 30 psi pressure.
Most of the manufacturers also list min pressure what mostly is 50% of max pressure, so I would not go below 60 psi, but wait, isn't 60 what the other guys are pumping?
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Yea its a dually. Not sure what most guys are running. However when I called american force they said they send out there big rig kits with 60psi. Just wasnt sure if that was to low or not. Especially with towing.
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I looked at those. They look nice but expensive. I have the beads in the tires right now. Was thinking of taking them out and road force balancing the tires.
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