Rim offset and lowering question
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rosspulliam
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The issue isn't the 22" size it's the lack of sidewall required to have a short enough overall tire height to maintain clearance on a lowered Super Duty. In order to get weight rating you must have sidewall, as the sidewall shrinks so does the weight rating of the tire.
Considering the rear of the truck: 305/45R22 in the STII lineup has a rating of 176 lbs lower, is just under an inch taller, and is the same width as the 305/50R20 (2910 lbs vs 3086 lbs). The rear is really a non-issue.
The front is where it gets tougher: The front of these trucks is pretty heavy, somewhere north of 4000 pounds on my truck. I want to say 4400 though it's been awhile since I've been across a scale. That puts us in the realm of around 2200 per tire just to carry the empty truck, or a load rating of 108. In the STII lineup that leaves the following tire sizes: 285/40R22, 265/45R22, 285/45R22, 305/40R22, 305/45R22. Only the 285 and 305 sizes provide sufficient carrying capacity to meet the full front load of 4800 pounds my truck has on the door sticker. I'm not sure if the 285/305 widths will clear on a 0 or positive offset wheel, it will be tight. The 275/55R20 handles the weight of the heavy front with lots of room to spare and gives me a slightly narrower width to more easily tuck the tire with a more positive offset wheel (both goals of mine).
In the end, my decision was made for me because the wheels I like come in 20" and not 22".
I selected my tire sizes based both on fitment and weight rating. Toyo Proxes ST II 275/55R20 (2833 lbs per tire rating) on the front and 305/50R20 (3086) lbs per tire rating) on the rear. Wheels will be 20x9 Raceline 932DM Twist Dark Tint. Door sticker weights are 4800 on the front and 6084 on the rear. This configuration gets me a satisfactory look and maintaining tires with a printed weight rating that is higher than the door sticker (with the exception of the change from LT to P). I wanted to be as close to or over the door sticker ratings just for peace of mind, regardless of it's relevance.
Does it really matter? Maybe not, but that's what I've settled on. I'm just waiting to order wheels/tires until the drop is installed and I can confirm clearance with the +12 offset wheels (otherwise I'll order 0 offset wheels). My suspension parts are at powder coat until Friday, and then I can work on finding a weekend to get them installed.
In the end, if you take nothing else away from my post, you'll at least know that I over analyze the sh!t out of everything. :redspotdance:
Considering the rear of the truck: 305/45R22 in the STII lineup has a rating of 176 lbs lower, is just under an inch taller, and is the same width as the 305/50R20 (2910 lbs vs 3086 lbs). The rear is really a non-issue.
The front is where it gets tougher: The front of these trucks is pretty heavy, somewhere north of 4000 pounds on my truck. I want to say 4400 though it's been awhile since I've been across a scale. That puts us in the realm of around 2200 per tire just to carry the empty truck, or a load rating of 108. In the STII lineup that leaves the following tire sizes: 285/40R22, 265/45R22, 285/45R22, 305/40R22, 305/45R22. Only the 285 and 305 sizes provide sufficient carrying capacity to meet the full front load of 4800 pounds my truck has on the door sticker. I'm not sure if the 285/305 widths will clear on a 0 or positive offset wheel, it will be tight. The 275/55R20 handles the weight of the heavy front with lots of room to spare and gives me a slightly narrower width to more easily tuck the tire with a more positive offset wheel (both goals of mine).
In the end, my decision was made for me because the wheels I like come in 20" and not 22".
I selected my tire sizes based both on fitment and weight rating. Toyo Proxes ST II 275/55R20 (2833 lbs per tire rating) on the front and 305/50R20 (3086) lbs per tire rating) on the rear. Wheels will be 20x9 Raceline 932DM Twist Dark Tint. Door sticker weights are 4800 on the front and 6084 on the rear. This configuration gets me a satisfactory look and maintaining tires with a printed weight rating that is higher than the door sticker (with the exception of the change from LT to P). I wanted to be as close to or over the door sticker ratings just for peace of mind, regardless of it's relevance.
Does it really matter? Maybe not, but that's what I've settled on. I'm just waiting to order wheels/tires until the drop is installed and I can confirm clearance with the +12 offset wheels (otherwise I'll order 0 offset wheels). My suspension parts are at powder coat until Friday, and then I can work on finding a weekend to get them installed.
In the end, if you take nothing else away from my post, you'll at least know that I over analyze the sh!t out of everything. :redspotdance:
Thank you. That's the most helpful post I've read. I appreciate the time you took for that.
It makes sense. And I think I could easily get 22" and be fine. But after reading that I might just do 20" for peace of mind.
I like that rim... Very good looking. I'm also looking at 20x9 in the Metal Mulisha. And I was curious about the 0 offset also vs a positive offset. You will be ahead of me so I can sit back and see what you do ha.
I assume you are using the DJM drop kit?
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It makes sense. And I think I could easily get 22" and be fine. But after reading that I might just do 20" for peace of mind.
I like that rim... Very good looking. I'm also looking at 20x9 in the Metal Mulisha. And I was curious about the 0 offset also vs a positive offset. You will be ahead of me so I can sit back and see what you do ha.
I assume you are using the DJM drop kit?
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rosspulliam
Member
You might shop tires and see what's out there. There might be some 22s that come with higher tire ratings than the STII tires do. A buddy of mine that works in a hot rod shop has had a lot of experience with the Nitto 420s that seems to be popular but he hates them and will never use them. I trust his opinion enough to not even consider that tire.
The STII has, from my research, been a pretty well regarded tire, it meets the load requirements I want in the sizes I'm looking for, and seems to have mostly positive reviews. When the wheel I want locked me into 20" I quit looking at 22s so I didn't do a ton of research into them or what brand offered the best load ratings in various sizes.
Not to say there aren't other tire offerings that might be better, this one just looks like a good option to me.
Yes I'm using the DJM beams, hangers and shackles but not their shocks.
The STII has, from my research, been a pretty well regarded tire, it meets the load requirements I want in the sizes I'm looking for, and seems to have mostly positive reviews. When the wheel I want locked me into 20" I quit looking at 22s so I didn't do a ton of research into them or what brand offered the best load ratings in various sizes.
Not to say there aren't other tire offerings that might be better, this one just looks like a good option to me.
Yes I'm using the DJM beams, hangers and shackles but not their shocks.
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rosspulliam
Member
DJM front and rear
So I think I'm going to go ahead and go with 20" and I'm looking at 305/50r20 all the way around. I like the idea of what you mentioned above about narrower in the front but I'd like to be able to just rotate them and have the same all around.
And like you, I going to go with the Toyo Proxes. I'm curious to see how your drop goes.
I'm ordering a few parts for my truck such as a compressor wheel, up pipes, etc first. I have a boost leak I need to track down also. No use dumping all this money into a drop and rim and not have the truck running top notch.
I'm thinking August will be when I drop it.
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And like you, I going to go with the Toyo Proxes. I'm curious to see how your drop goes.
I'm ordering a few parts for my truck such as a compressor wheel, up pipes, etc first. I have a boost leak I need to track down also. No use dumping all this money into a drop and rim and not have the truck running top notch.
I'm thinking August will be when I drop it.
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rosspulliam
Member
Cool, hopefully I'm dropped by then! Parts should be back from powder coat this week sometime, and then I just have to figure out how to find time to install them. I'm holding off ordering wheels until the drop is installed so that I can verify what offset I need to order measuring the truck at ride height.
I like it. So that's a +10 offset? Hmmmm. Was hoping to tuck them in a tad more. Would u mind a straight on pic one day?
Freaking love the look of your truck overall. Great good on it.
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UNBROKEN
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You're overthinking the offset thing. A 10" wheel at zero offset is as wide as will tuck. Anything narrower is even easier. That won't change with the drop.
Again...10" wide and zero offset will tuck. I'm speaking from experience.
Ok. Makes sense. I appreciate it. I've looked at a couple rims that I think I'll end up with. And the couple that I like are either 20x10 or 20x9.5
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rosspulliam
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Unbroken, I understand, and I probably am. However if I can get the extra half inch from the +12 I'm going to take it. I'd rather have the wheels under the fender not just even with it. I know the +0 offset will fit, I'm not sure if the +12 will fit.
I think it will, but wanted to drop it and take a look at where things are ending up and then make my final decision.
I think it will, but wanted to drop it and take a look at where things are ending up and then make my final decision.
Thank u for the pics. Love that paint job too. Very helpful.
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A +12 10" wheel with a 305/50/20 will rub the radius arm like crazy. A +12 9.5" wheel will rub pretty bad too. A zero offset 10" wheel will just touch enough to rub off a little paint.
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I had 10-11 sets of wheels on my dropped 04 truck. If my failures can help someone else then that's why we're here. lol
rosspulliam
Member
What about a +12 275/55R20 on a 20x9" rim on the front hitting the radius arm? lol
+12 305/50R20 (again 20x9) are for the back and should clear fine (I think)
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Play around with the link I posted in this thread. It's super helpful for fine tuning wheel fitment.
http://powerstrokearmy.com/forums/showthread.php?t=6229
Use the backspace number for a 10" zero offset wheel as a baseline and you can see how much more or less clearance you'll have with other sizes and offsets.
http://powerstrokearmy.com/forums/showthread.php?t=6229
Use the backspace number for a 10" zero offset wheel as a baseline and you can see how much more or less clearance you'll have with other sizes and offsets.
