Disc brakes on a BB w/20" wheels?

[rainh8r]

I'm starting on a 34 BB 1 1/2 ton flatbed that will be running modern power and rear end, but I'd like to get good front brakes too. I'm trying to keep the original look with 20" steel wheels, so I'm wondering if anyone else has done this with modern brakes? I'm considering some of the later model drums, as they use a similar wheel, but would really like to find discs that work up front on a solid axle. Any ideas? Thanks, Rob

[truckdog62563]

I've been watching this go unanswered for a few days now, so will at least see if I can connect you with somebody that's done a similar conversion. Our member "51dueller" over on the 48-60 forum has done this with his 51 Mercury M-68 (same as a Ford F-3). Here's a link to his gallery.

Ford Truck Enthusiasts User Gallery

What you are hoping to do is gonna be much more difficult because you're trying to keep your stock wheels. Your wheels are the old Budd style that have 5 lugs on a 6 7/8" bolt circle, if I remember correctly. Ford changed to the more common 5 lug on an 8" circle in 1935 I believe. The only other vehicles I know of that used that 6 7/8" bolt pattern were Dodge on WWII era Power Wagons with dual wheel type hubs, and Ford on war era tonners in a single wheel hub configuration. You could swap in a whole rear end from one of them, but you'd still have gear ratio issues to deal with.

So another angle would be to swap in axles/hubs from a later year truck having the 5 lug x 8" circle wheels. They would at least look original. They will be pretty common, but will still leave you gear ratio issues.

To fix the gear ratio problem you could find a Ford 9" or Dana 60 axle and adapt it to one of the old bolt patterns. On my Marmon Herrington trucks the factory mounted rear adapters to convert the stock rear axle with its 8 lug x 6.5" bolt circle to the bigger 5 lug x 8" circle. Here's a pic of one. You might be able to have some made similer to this. One company that does this type adapter is Arrowcraft. Here's their web site: http://www.arrowcraft.com/



On the front I think you'll be adapting later hubs fit your spindles, then working out the geometry of adapting disc brakes to all that. Swapping in a whole modern front axle would be your desire, but then you've got steering/pitman arm/drag link issues to deal with. The steering designs used on modern trucks is much different than on the old ones. Hope that gives you some things to think about. Stu

[rainh8r]

Thanks for the help. I like the looks of the older Budd wheels, but the newer ones are just about the same and will still have the look I'm after. I didn't considered adapters like MH used-that's interesting. I'd like to find a newer axle that would work under the truck but everything late is dual spring instead of cross spring and wider, so narrowing the axle would be necessary to fit the wheels under the fenders. There are lots of 8 lug options that end up with 16 or 17" wheels, but they don't have the same look. This will be a working truck, so I may end up with 8 lug just to have parts availability. I know where there is a 68 C600 sitting around so I may see how the front hubs/spindles look. I was hoping someone else had done this, as I'm familiar with lots of the lighter duty truck parts but not the larger ones. Rob

[truckdog62563]

You may have no choice but to add new spring perches to allow donor axles to mount. Most later trucks will have a SAE standard (I think it's) 32" wide front frames and 34" wide rear frames. If yours fits that standard you'll have an easier time finding donors. A lot of our 48-60 guys have luck using 67-72 donor rears because they bolt right in. And (you'll now see that I've had ideas of doing a similar swap) I've been told that 1971 F-250 spindles with disc brake mounts will fit a 48-52 from axle. Steering would still, though, have to be addressed.

Your C-600 might have the 5 lug x 8" circle wheels, but could also have 6 lug x 8.75" circle. If you can adapt those hubs you may have to accept the 6 lug set up. Be careful, though, that you don't get yourself into dealing with the "widow maker" style split rims. I'll post a couple pictures here to show you what they look like. Nobody will work on them anymore. Also, the late 60s is when Ford introduced "hub piloted" mounting on some models. Earlier trucks were "stud piloted".




Having Chassis Manual diagrams of different axle set ups would be helpful to you I think. There's a 67-72 site called Fordification that has a section with diagrams. There's bad blood between them and FTE so I can't link the site. You might want to do a Google search. Stu

[rainh8r]

Great information-thanks again. I was thinking about ways to mount the cross spring off brackets bolted to the spring pads of a dual spring front axle, maybe off a F450 or other HD series body. The width is the the problem there, as they are all wider than the truck I have. I do have a couple of 9" rear ends from the 67-72 pickups from my F100 projects and a Dana 70, so something could work there with adapters to the 20" wheels. I'll be steering with a power box, probably a saginaw with the Dodge 4x4 mount that steers out the left side to the LF wheel. Cross steering is nice, but may not fit in this application. I didn't know about the F250 spindles fitting the 48-up axle-that may be an answer to machine work to make things fit older hubs (I'd like to use newer parts). Thanks, Rob

[truckdog62563]

Good luck with it. Stu