I was rummaging around in some stuff this morning and came across some old Chevy ('49 to ??) backing plates and drums/hubs. I'm pretty sure they came from a pickup axle I had for a project a long time ago, but I was surprised they were 5 X 4 3/4" pattern. I thought pickups would have been 6-lug, but maybe I'm wrong. Anyway....I have a drop, tube axle for Chevy spindles that came with Pinto/MII discs and the Chevy spindles that are modified for the disc brake hubs/rotors. I got checking to see if I had the parts to go back to drums if I would ever use the axle. I knew there is a difference in backing plate mounting hole spacing between car and truck spindles, but in checking a set of what I think to be stock, car spindles into the backing plates, it appears the top pair of bolts line up. The backing plate would have to be re-drilled for the bottom 2 bolts for the backing plate to fit on the car spindles. Just holding things together even the spacers appear to be about the right length and the center hole for the axle stub would line everything up to do the re-drill. The backing plates have what I would call "Bendix" brakes (adjuster at the bottom), rather than "Huck" style that have the adjusters built into the wheel cylinder. The shoes measure about 11 1/2" diameter but I didn't check shoe width. There's a slight interference between the top of the spindle casting and the wheel cylinder hydraulic fitting, but it seems a tiny bit of grinding on the spindle and the wheel cylinder casting would make enough clearance. So....all that leads to my question and that is, has anyone done such a conversion using re-drilled truck backing plates on car spindles? Are there pitfalls that I didn't see to making the adaptation? I suppose I could find Chevy car backing plates easily enough, but I'd like to make use of what I have rather than buying even more stuff. I'm really trying to reduce and use from my parts stash, and getting "Bendix" brakes in the process would be nice. Thanks Lynn
This may help answer your question. When I was in high school I drove a 48 chevy truck with the 6 lug wheel pattern. Wanting to change to chevy 5 lug wheels, I took the spindles off of a ,I believe, 50 or 51 chevy car. To install them on the truck, all I had to to was re-drill the bottom two bolt holes. Everything was kept stock including the drum brakes. I don't remember having to do anything else. I hope I'm telling you this correctly as that was a long time ago !! Should'nt be hard to mock up to verify without spending money giving the description of the parts your trying to use.
figure out how to get pictures on here, so we can see what you have. Huck brakes were used on cars and trucks through 1950, so they would be 51 or newer. The truck bendix brakes from 51-59 fit on the earlier solid axle car spindles, with some adapting for different size bolts, etc. The 51-54 car hubs will replace the 51-59 truck six lug hubs easily. There was a change in inner bearing ID somewhere between the early 30s and the 50s, so you have to make sure the bearing matches the spindle you are using.
It should work with a little massaging of parts...... What steering arms do you plan to use? I have a Chevy PU axle('55?) under my <<coupe, using the PU brakes and car hubs(5 on 4 3/4"). I used the car steering arms to get away from the old ball and socket design, but I modified the backing plates a bit and they worked fine.
Thanks to all. Sounds like what I have has a good chance of fitting together with just a little fitting and drilling. I'll dig the parts out again and get a couple photos, but it might be a couple days. Doing something with these parts is not a rush by any means since it would be for "future" project #2 or 3. How knows....it might be info and documentation someone else would want some day though. Lynn
Reidy....that's a very helpful article. I think somewhere in there I came to believe what I hope to do will actually work. Fiddling around this afternoon backed that up. Apparently what I have are '52-'59 pickup backing plates and '52-'54 passenger car hubs/drums. I've included a few photos of the spindles and brakes I have. Turns out there isn't any interference between the top of the spindle and the fitting for the wheel cylinder after all. I bolted the backing plate to the spindle with the top two bolts which lined the axle in the center of the backing plate just fine. Since the backing plates were originally on a pickup the lower two holes in the spindle did not line up with the holes, and I knew they wouldn't. Bolts were also 1/2" in the pickup backing plates where the passenger spindles have a 7/16" hole, but the spacers seem the right length. Simple enough to make some new spacers. It appears it will just be a matter of drilling the backing plate to line up with the lower two holes in the spindle and I'll have Bendix brakes. I'm almost positive the tube axle I have has the kingpin inclination for 49'-'54 passenger car spindles as I've never seen a tube axle listed for use with pickup spindles. If it weren't for the inner races for the inside hub bearings being AWOL I could put the parts back where I found them knowing I can make use of them someday with my tube axle. Thanks to all! Maybe this and the photos will help someone else as well. Lynn .
Maybe double check to be sure the spindle snout wasn't machined to adapt the disc brake hubs; used to be a pretty common thing.
The spindles that are on the tube axle currently (not pictured) have been machined for the disc brake hubs, but the spindle in the photos is a stock spindle. in case I decide to change back from disc to drum brakes. Lynn
The red primered spindles in the photos are a stock pair I've had for a long time. The spindles that are currently on the tube axle (not pictured) are indeed modified for discs. I'll probably list the modified pair along with the hubs/rotors and caliper brackets for sale at some point. As I see it, all I need to do is drill 4 holes (2 in each backing plate) then clean, check and refresh re-fresh wheel cylinders shoes and bearings as needed. Lynn
...I think those backing plates are Chevy pass. car ...51-54,...Here's pics of my 37 Chevy car axle that I put 51 Chev car brakes on,..only needed to redrill lower holes in backing plates,...you need spacers like those you've shown,... I used Speedway steering arms on spindles and their steering /tie rods,...you can get them made to your specs for length. ..I went with cross-steering,made my own steer. box mount for 65 Chevy (Malibu)manual steering box,,...works really well.
We used the stock steering arms most all the time "back when". When we needed something different; I cut the arms out of 3/4" plate and welded them to two pieces of heavy wall DOM used as the spacers. This way the arms were thick enough to drill and taper for tie rod ends instead of heim ends. Upper steering arms for side steer were made this way also.
AS the others said, swapping 51/54 Chevy car (Bendix) 5 lug backing plates and drums and hubs to AD trucks and the drums to TF trucks has been standard procedure to get 5 on 4-3/4 bolt pattern for years. I first did mine in 1973. Along with drilling two new holes to match the truck spindle you have to make two spacers to fill the gap between the backing plate and the spindle. On the earlier rigs you also have to mix and match inner bearings to get the right size inner races as the spindle diameter is a tad smaller.
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