Drum size question

[doublehfarm]

Axle is in a 73. Guess it could have been changed at some point, but I’m seeing 11 inch with 2 1/4 shoes. Everything I read says 76-77 ?? Backing plate is benedix 3208560 and 3208561. Not a big deal just trying to get new wheel cylinders. So what you guys think ? Disc / drum. Thank you

 

[Viperwolf1]

I don't recognize those part numbers as '76-'77 parts, but I do find a reference for '92-'95 F150 8.8 brake backing plates.

 

[doublehfarm]

I don't recognize those part numbers as '76-'77 parts, but I do find a reference for '92-'95 F150 8.8 brake backing plates.

It has me confused as well. Is there a stamp on the axle somewhere that would clarify ?

 

[doublehfarm]

 

[Tiko433]

I remember around those years they did a small bearing big drum.. I think they called it a HD axle. The parts store would always tell me I needed the wrong size.
Someone more knowledgeable can chime in and clear it up

 

[DirtDonk]

Is there a stamp on the axle somewhere that would clarify ?

Take a picture of the axle and show us. If it’s a 9 inch, we’ll know. If it’s an 8.8 inch we’ll know.
Or maybe you know that already?
If not, and in lieu of a picture, is there a rear cover on the differential that bolts on? Or is it a solid housing as is typical of a 9 inch?
This may not help with the brake issue, but it will at least clear up what axle/differential you are running. And if the whole thing was swapped, or just the brakes.

One reason a picture might be better, is if somebody swapped in an entire housing out of a 77.
Maybe that’s how you got the bigger brakes and would show that you hopefully also have the correct axle shafts.
Because flange offset matters with brake choice.

 

[doublehfarm]

Take a picture of the axle and show us. If it’s a 9 inch, we’ll know. If it’s an 8.8 inch we’ll know.
Or maybe you know that already?
If not, and in lieu of a picture, is there a rear cover on the differential that bolts on? Or is it a solid housing as is typical of a 9 inch?
This may not help with the brake issue, but it will at least clear up what axle/differential you are running. And if the whole thing was swapped, or just the brakes.

One reason a picture might be better, is if somebody swapped in an entire housing out of a 77.
Maybe that’s how you got the bigger brakes and would show that you hopefully also have the correct axle shafts.
Because flange offset matters with brake choice.

Thank you sir I’ll will get those later today

 

[doublehfarm]

Here are some more pics. Pretty sure ford 9 with a bronco axle. Measures 58 hub to hub on outside. Back spacing to axle is 2 inches

 

[Viperwolf1]

Looks like F150 brakes bolted onto a small bearing axle. What's it look like on the other side of the backing plate? Are the mounting holes the same or was it redrilled?

 

[doublehfarm]

Pic from front side. They won’t look drilled out.

 

[doublehfarm]

Im just trying to rebuild these brakes but not sure exactly what to pick up at parts house. Thanks

 

[73azbronco]

yeah i have a 73 big drum, big bearing, had a heck of a time determining what was what seemed parts never fit, then i just bought them all and put it together. Sorry, can't help much beyond buy various sizes try them return those that dont work.

 

[Jdgephar]

Appears to be a '77 setup. Axle flange spacing is same as a '77. Do your drums install all the way up to the backing plate when they are installed?

My '72 has the big bearing HD axle. When it was swapped to 31 spline axles, the flange spacing was changed to the '77 style. But the PO kept the 72 backing plate, so '72 11" brakes didn't install correctly, and neither would '77. I had spare later model F150 9" axles, so I used the backing plates from them and used all '77 11" parts.

See here:
https://classicbroncos.com/forums/threads/rear-drum-brakes.299238/

This looks like a small bearing axle...so ?

 

[Jdgephar]

My only other clue (but not necessarily good information) is a question posted in a 1967 - 1972 F-100 & Larger F-Series Trucks forum. There was no answer to the question of what Bendix part #'s 3208006-R & 3208560-L fit.

 

[doublehfarm]

thanks for all the info... thinking I will just get new 2 1/4 shoes and try to locate the larger drums. any guess on wheel cylinders?

 

[dmoses42]

Not sure if this will help, but... I googled the 3208560-L number and got an Ebay listing, stating 8.8 for F150 and Bronco. So I went to Rockauto and looked at an 88 Bronco (since 86 was the last year for the 9") and looked at brake shoes. Wagner has a set there that is stated to be 11-1/32 x 2-1/4 (Z263R) so I'm guessing that is what was swapped on there, 8.8 backing plates from a 87-96 Bronco or F150. No idea if that is correct for brake spacing and such, but that is where I'd start looking for parts if it was operating as it should before you got in there.