My 56 F350 (I named it Brutus) was originally a 9 foot Express pickup but I plan to make it a flatbed dually. Far cheaper that way (about $3000 less!) & easier to refurbish it. The old 5.14 geared rear end went to the scrapyard last week. I've seen a number of later year rear axles with mostly a ratio of 3.73 or 4.10. Which is better? The jury's still out if I'm going to run an original Y-block or maybe an FE block.

The best choice I'm thinking is a 1965-66 rear as it would be the same bolt pattern as my stock front wheels but if I have to have 2 separate spares, oh well.
Imput?

 

Unless you're hauling something- I'd go with the lowest ratio you could find. 4.10 or 3.73 is still an improvement over 5.14 but if there's something you can find in the lower 3.xx's, it'll cruise better at highway speed.

 

With is your bolt pattern ? My 250 is 8 lug 6.5 ( if I remember right). I'm looking into a dana 70 or sterling 10.25 from a cab and chassis F350.

 

53 to 66 f350 were six lugs on 7.25 or something close to that. For the rear axle Im used a sterling 10 1/4 from a 92 f350. 4.11 ratio. I have no problem doing 65. Running 255 85 16 tires that are 33" tall. I then converted my front hubs to the same 8 lug pattern. If you do a search for six lug to eight lug f350, maybe you can find my post or two about converting the front. The front drum is bolted to the hub using the eight on six and a half pattern. I cut the outer six lug flange off and bolted a common toledo adapter for duallies to it. Some machining and welding required,but pretty easy.

 

How did you fit a 255/85R16 on a 16x6" dually wheel? Minimum wheel width of those tires is 6.5" and recommended is 7".

 

Using the '92 wheels. Not sure of the width, but the tire is the same cross section as the common 235 85 16, just taller. My truck is an express 9' flareside, so I'm running singles. I do however run the 255s on my 92 f350 dually service truck, and the 54 gmc dually flatbed I sold last week. My wife's nephew worked at a tire store for 13 years, and at a recent family get together he was very doubtful that a set of 255s would leave enough space between the tires for safe running. I then took him outside and he slid his hand between them ad admitted he was wrong. Lots of room. Tires vary a lot with manufacturers and the ones on the rear of my '59 do look wider than the other sets which are 'dean' brand, from the well known tire store Les Schwabb here in the western states. Im away from home right now and can't do photos, but if you care to see a picture, go to the 57 60 forum and look at a post called ' low to no cost lower' where I post up a picture of my version,which raises the truck a bit. Oh, and since this post was about rear axles, keep in mindthere are two widths. Cab and chassis or dually pickup. Thr former is considerably narrower.

 

Ford only used one size of dually rim from 1985-2004 and it was 16x6. There were several offsets 5", 5.15" and 5.35" (different bolt pattern for 1999-2004). 5.35" was designed for 235/85R16 duals. A 255/85R16 is 3/4" wider than a 235/85R16 plus being 1.5" taller. I know you can physically make it fit a 6" wide rim but it is designed for a 7" which is no problem for SRW.

I'd just like to run a tire equivalent of a 7.50x17".

 

Still on topic, we are talking about axle swaps.
When did Ford change from the lug centric dually wheel to the hub centric wheel? Did the hub centric wheels come along with the Sterling axle or before? The lug centric dually wheels are getting hard to find in my area. The hub centrics are plentiful.

 

I lived,ate,slept and breathed 7.50 17s for thirty years. I have owned many one ton pickups, mostly fords,but also chev and jeep m715. The 255s are the closest thing I have found in a modern radial, ok michellin makes a 750 17 for 359.00. Seriously, tires by different manufacturers vary greatly in ht and width. You can tell from a hundred feet away the 255s 85 16s on the rear of my '59 are much wider than the same numerical size I bought at Les Schwabb. So perhaps we are both right. I'm on vacation right now, but on Wednesday I could measure the width of both brands, both on '92 ford dually rims.

 

Sorry, you're right. Back to axles it is

 

I sure hope you did not think I was being an *** by prefacing my post with still on topic. Not at all, I was just trying to expand the subject since you and 51 Dueller seem to know this subject.

Edit: I just did an axle swap to my '49 F4 to a Dana 70 and would like to do the similar to the '56.

 

Any F-350 or E-350 built after 1/1/84 uses hub centric wheels. If want to use hub centric wheels on an older Dana 70, you will need rear hubs off a 1985-1998 E-350 with drums. Some 1996-98 E-350 Superdutys were equipped with rear disc. So don't be like me and accidentally end up with disc brake hubs.

 

Good information. Reps given previously so thanks only.

 

Also, jic I was missunderstood, it's the axle that comes in two different widths, not the wheels. Dually pickup axles have room for a 4' sheet of plywood between the fenders, no way on the cab/chassis type of dually. I own both types of 10 1/4" sterling. Thats why dually pickups look so wide when you are behind one. 'Cause they are . And lots of good info here, I continue to learn. Thanks. Ok, one more thing on this subject... Why is there that stub on the dually wheels so they can only go on one way? It 's hard enough for an old geezer to mount them already without exact line up for that crazy 1/4" stud thing. Done with rant, getting on plane for home tonight, after my evening cocktail(s)

 

Not entirely sure why only original Ford dually wheels have that little stub. Looks like your missing the hardened roll pin that is supposed to be in the hub. The roll pin makes it easy to line up the wheels and if you had the outer wheel, it makes sure you can check air pressure.

Chevy trucks don't have the roll pin so you can miss-align the wheels so you can't check air pressure.