Posting here from another forum for you guys.


Well I got tired of waiting for the custom hubs for my 10.5 conversion so I decided to experiment with the hubs. I have a few sets of hubs so I'm gonna play around with them some more. First I redrilled the 8 on 6.5 between the original 8 on 170 holes to get the OBS pattern. This is easy and doesn't cost much to do and the correct bolt pattern. You can use off the shelf wheel studs if you do it this way.

My next set of hubs should be done soon, hopefully in a week if I have the time to do them. With these hubs I plan on going thru the existing 8 on 170 holes, using a larger wheel stud and machine the stud down for the 9/16. I think this will be a "cleaner" way to do it but alot more time and money. Its really not needed as the dual pattern hub is plenty strong enough. The flange is 1/2 thick. Here are some pics of the work so far...









On this pic I went thru the one of the 8 on 170 holes and was almost able to use the stock wheel studs. Its close, but not close enough, so the larger knurled studs should work fine.



Here is a pic of how much the bolt pattern is off. Not much. (8 on 170 hub to the 8 on 6.5 rotor)

 

Here is where I machined the off the shelf wheel studs to the correct 9/16 for the obs pattern.







Left, off the shelf stud. Middle, machined stud, right, OEM F and E series stud.

 

So with this, you get a wider rear axle to match the front. Real disc brakes made for a 1 ton truck and a carrier that is stronger. And a parking brake that will work like it should.

 

Very nice! So this would allow you to use the 10.5 rear in an OBS with 8 on 6.5 wheels correct? And you're able to do it by machining out the hubs to fit the oversize studs and then installing the oversize studs into the machined hub.

If you could design a system that would allow someone to field modify(or essentially drill) out their own hubs without having to have them machined out with a mill and then install your custom studs, you could sell a lot of those studs. My guess is that it is tough to drill the hubs out to the correct spacing without having the hub clamped in place on a mill, even with the oversize holes. If there was a way that the average Joe could modify the hub with the use of a hand drill or even a drill press, you would have a VERY marketable product on your hands.

All that being the case, I think the best route for the average shade tree mechanic who doesn't have a full on machine shop at his disposal would be to do what you did in the first place there and just drill out their own holes in the hub. I'm also curious what the 8 on 6.5 rotor for the hubs you have pictured is from.

 

So what are you going to do for rotors, E series rotors I presume?

 

How about Van rotors. They are 8X6.5. Or even find a full van rear axle and do the swap.

I too would be interested in a set of those machined studs. Got a price for 16?

 

Correct E350 rear rotors.

 

The bolt company I work with is going to quote it out and I'll let you guys know what they would cost.

 

Will a van axle bolt up to a F250 or will you have to move the spring mounts ?

 

Couple things wrong with that axle.

Wrong spring perches
Offset pumpkin
Axle shafts not as strong
Smaller ring pinion (if I remember right)

 

Your correct with the 10.5 to be used. I won't be getting involved in a "kit" to drill out your hubs. It's not worth the liability. And a local machine shop can do the hubs easier and drilled right. I may do a group buy and have the studs made if there is enough interest. Basically I was just showing how to do this so you can run the sd rear axle.

 

Can you buy just the hubs? I'm thinking rather than swap the whole axle a guy could swap hubs and run the van rotors to save on cost a little.

 

Q... what is the real upgrade here? i am not familiar with the differences between SD and OBS hubs.
Thanks for the info.

 

You get disc brakes and 3.73 gears

 

ooh, would be very nice