oh shoot, if that's the only reason then I would just run reg. rims and rotate the fronts between each other and make your spare a reg. rim incase you blow a front tire. cuz you can run on 1 tire on one side if you blow one in the rear. rear tires don't really need to be rotated because they don't wear unevenly unless something is wrong with your axle. if you do that then you can run your rear tires about 2-3 times as long as a set of fronts. and then that huge bill for 6 tires only comes like once the whole time you own the truck

 

its christmas in july!!!!!! i called the guy up on this and he said he would sell me the axle with it for $450!


F 350 Dually Bed

 

The SRW and Dually axles are interchangable. Same frames on the regular F250's and F350's SRW and Dually.
The cab and chassis (F-Superduty) has a narrower axle and frame.

 

The dually rear axle is 4" wider overall. Unless it's a cab and chassis axle, then it's 4 " narrower than a SRW axle.

The dually wheels won't clear the springs on a SRW rear axle. Other than the 4" extra width and different size brakes the axles are the same though.

 

I would rather do it the correct way, I see what your saying but it was done this way for a reason. also IMO a local guy did a dually conversion on a F250 and it looks stupid with regular front wheels. But hey there is nothing wrong with it and its your truck, if it makes you happy I am happy =)

 

I wish I had kept mine a dually...and kept the 4.10 gears.

Actually I wish I could have the dually but the same width as the SRW. I don't like the rear fenders and tires sticking out that far.

I need a cab and chassis frame and rear end. haha

 

The substiture teacher for the autoshop when I was in school drove a cab/chassis truck with a welding rig on back, was a great truck, 5 spd.

 

So my 250 SRW and a 350 SRW have the same everything. But the 350 DRW has a wider axle because the tires won't clear the springs... i guess, because I don't have both axles and a tape measure in front of me i'll have to take your word for it, but I have always thought they were the same axle just with a dually set of rims, that's why the outside rim is so neg. offset, so the inside tire cleared the springs... oh but you said you did the conversion, so you have had both axles in hand... i'll shut up haha. Ah, how nice it is to dream about the things I would love to do with my truck but can't afford... Anybody have a CC 350 psd 4x4 that's willing to donate to my dream fund? I think I have $3.... and i'll give you my truck haha

 

To answer your first question, No, it doesnt add extra stress to the outer wheel bearing. The stress is the same whether you run a SWB or a DWR set-up. I know the appearance can seem that you are adding stress to the outer wheel bearing because of the point of stress, but its the same on a SWB. Nothing changes. You are still applying the same amount of force to the outer hub assembly on both versions. By extending the mounting surface you would think you would apply more pressure, but the placement of the mounting surface of the wheel in combination with the wheel contact to the ground remains the same on a dually as compared to a SWB.

Now if you were to flip the wheel outward, then yes, you would add more force to the outer wheel bearing, but that is due to the point of contact for pressure and stress changing and placed out further.

For the second question, yes and no. You can use just duals in the rear, while a single set up in the front. But no, there is a difference with the rear axle as Brown Falcon stated. The axle is longer in the rear, which again goes back to your first question in an answer. By spacing the wheels further apart on an axle you can carry a heavier load, based on the build of the axle and the capability of the wheel assembly (duals). It has to do with weight per PSI. If you spread your weight over a larger area, your PSI drops. By having twice the contact area on the tires, you dont bring the load ratio down, hence the dually.

Those are the explinations for the front and rear axles. As for why the front shares the same wheel for the rear, I think it was answered already, which is interchangability. You go running down the road and have a flat, you dont want to have to carry around two different spares, one for the front wheel design, and one for the rear wheel design. You are also able to swap wheels on the road if you have a flat, and dont have a spare. You move your flat to the inside of the dual rear, while moving one of the rears up front. This is good for short range, and even shorter distances under load.

Hope that helps!

 

Not quite same everything.. Then there would be no F-250 or F-350 models that are sold differently. The F-350 utilizes different rear springs for more payload. I will see if I can go out and get some measurements to help clarify this for you, as I have both set-ups out back.

The axles for the rear I do believe are the same, but I will have to double check first. What the major difference is between the two, other then one being dually and one being single, when it comes to the axle itself, is the spring mounting locations. Let me see about getting some pics and specs up to see if that can help a little!

 

I was told by a bunch of folks that the spring packs for the 250hd and the 350 in the rear were the same. That the only difference between the 250hd and the 350 was the d50 ttb in front and the d60 on the 350. That was from a ford heavy line mech. when i was talking to him about my truck when i first go it. I think I'm happy with the rear springs, might want a heavier load spring, it does tend to sag alot with a heavier trailer... But I plan on bagging the rear end anyway, so I should be fine if I just get a heavier duty bag. I'm going with upgraded front brakes, and one day a d60 swap with an RSK in front too. I want to make this thing a 350 so it can do what it sounds like it can do. once it's bagged in the rear and my brakes are replaced, im sure i'll be able to handle anything I might have to...

As for the wheel setup with the inside rear and fronts being the same, i get that... im just kinda not real partial to the way the inset rim looks in front... is there an actual difference with the rear axle housing? or is it just the drum having that spacer looking thing on the outside of it on both sides? like if I have a SRW axle, is there a part I can buy to make it a DRW axle? or is it two completely different animals? If you got pics midwest, that would be fantastic, im a visual learner hahaha. I'm the picture book kid, not the reader hahaha. you guys are great, i love this site, picking each others brains

 

I believe the differences are the longer (or wider) axle for the F-350 DWR, along with the spring perches. I dont want to get too far ahead of myself as my memory isnt so hot when it comes to the SWB dimensions, but I will check that out in the AM and have actual specs to refer to. That spacer you are referring to on the outside of the hub for the rear axle, is part of the inner axle shaft that runs to the differential. It bolts to the hub on the outside. This makes it alot easier to swap out inner axle shafts, especially when you strip them under painful loads and conditions.

To make that SWB rear axle just like a DRW axle, you will need to actually swap out the entire axle completely. Again, this is because of the length of the DRW axle, which is wider then the SWB rear axle.

But if a person is interested in the putting duals on their SWB truck, just for "asthetic" purposes, it can be done fairly easily. Now, if you want to put an actual DRW axle in, you will have to cut the spring perchs (or mounting plates) on the axle, and move them in closer to match up to your leaf springs. Unfortunately swapping out to a true DRW axle wont give you the same load capabilities as an actual DRW truck. The reason being is the space that is spread out on a DRW truck is greater then that of a SWB truck, as for chassis and bed mounts. This goes back to your question about why the spacing differences.

The best way to understand why a wider or bigger spacing difference between the two, and the benefits, is a blunt vs. sharp object test. Taking something such as phillips head screwdriver, and pressing the tip against the palm of your hand, that sharp pressure will be greater then if you use a flathead against the palm of your hand. You are spacing out the amount of pressure to the contact point surface.

Extra springs will give you more strength for your payload, it will also add some bounce to your ride, LOL! The airbags are a great option too! Those are all wonderful ideas. I think if you just wanted to get away with a simple DRW conversion like I originally posted, you will get benefits from that as well.. and that being more contact surface for you payload to the ground. Your tires will thank you, LOL! I have seen some pretty insane loads on a SWB truck before.. and the truck holds up, however, running that extreme weight on a SWB set-up, you have only one tire per side of truck to support all that weight you are carrying. You can see those tires squeal for relief as the bottom of the tire bulges out like mad. If you have a blow out while carrying a massive load, I am sure you can picture the damage to the wheel, along with control problems while running down the road.

You lucked out in the picture option here.. I am sending my donor SWB 97 F-250 off to salvage tomorrow night, then all I will have left around here are duallys! LOL! No worries about being pic oriented.. it helps a s@@t load, believe me!

Not that a person couldnt tell, but yes, I am very partial to duallys. When I went truck shopping, it was for a dually or nothing. I grew up with nothing but duallys on the ranch, and when I was old enough to get a truck of my own, I bought a SWB.. My regret with the things I do to trucks! It was short lived. I can personally attest to the fact that you can load up 3 round bales, each at 2200lbs onto the bed of an OBS dually truck, and safely make it home! I wanted to push it further with 4, but 3 fit nicely in a triangle stack on the bed, with some overhang. Needless to say, those are the things I end up doing to mine. The best part is, I dont have major repairs to contend with me pushing the envelope. So I understand wanting to get as much carrying capability as possible!

 

damn! three round bails? you're a madman! hahaha get a trailer man!

I understand spreading the load that you're hauling, but I need pics to fully understand how the springs are placed differently. my springs are already outside the framerails, so I dont see how you could get much further out than that without compromising the spring mount integrity. I understand the concept behind how duallies spread the load through 4 tires, and are more stable for towing with a wider stance and all. I guess I'm just all messed up because I always thought it was the same axle with different rim styles on it, that's all.

 

The housings are the same except the axle tubes are wider in the rear on the dually axle. No spacer on the stock dually axles. You can buy spacers to make your SRW axle work with dually wheels.

 

just want to clarify something because itss early in the morning and im still hungover. if i want to use my f250 spring packs the drw will match up. so even though its wider the perches are in the same spots on both axles? i planed on leaving the 250 springs and just bagging it or overloads.