What's the "heavy duty brake system?" I see it on Rockauto.

[robroy]

Good evening,

Lots of the brake parts on Rockauto say that they're for the "heavy duty brake system," or that they're for "H/D Brakes."

Some parts include "H/D Brakes" with "drum brakes," which makes me think that there was a heavy duty drum brake option for Bumpsides.

Is that what's going on?

Here's another way to phrase my question, which is probably more to the point: Are all Bumpside disc brakes the same? Like when it comes to ordering wheel bearings, seals, calipers, rotors, and hoses, as long as it's disc brakes and it's for a Bumpside, will it fit? Or were there any options or variations on Bumpside disc brakes?

Thanks!
-Robroy

[fordman]

i'm going to guess. and say that it could be that size of pads or size of the discs. or the size of the wheel cylinder or caliper fliud capcity. do you have a specific link for what your looking at?

[robroy]

Hi Fordman, thanks for your reply!

I can't provide a direct link to what I'm looking at, but I took a screen shot that shows a H/D and L/D brake option difference for different seals. In other parts of the Rockauto site I've seen the "heavy duty brakes" note where it doesn't also mention whether they're drum or disc brakes.



Thanks Fordman!
-Robroy

[fordman]

for those seals it seems to be talking about the size of the drum or disc bearing hole. whihc could mean that the hd have a larger bearing in the back part of it.

[robroy]

Hi Fordman! You're probably right. Since my truck's fifty miles away I can't easily go measure the rotors to see which size I need. But if I knew whether or not there were any variations on Bumpside disc brakes that would help. From what I've read, it seems like all Bumpside disc brakes were created equal. But maybe not!

Thanks Fordman!
-Robroy

[robroy]

I just found this 1972 truck option list in Keith's amazing library. It suggests that F250s were available with three different brake packages: standard brakes, which were 12 1/8" x 2" drums on the front and rear, "Power Disc Front," which included 12" x 2.5" rear drums, and "Heavy Duty Front & Rear," which had 12" x 2.5" drums on the front and rear.

So this means to me that the "Heavy Duty" option applies to drum brakes only, at least when parts pertaining to the front brakes are concerned.

Here's the sheet I found in Keith's collection:

http://www.fordification.com/lit/images ... bro_30.jpg

Thanks!
-Robroy

[papabug71]

robroy, the 72' F-350 my in-laws have ( the one I want soo bad) has the heavy duty brakes. Its not discs however, its power drums. The drums on the front of it are MASSIVE. They even have x-tra tall ribs, I would imagine for cooling. I have yet to see another truck with similar brakes, & I have looked at alot of 1 tons in the last 6 months.

I can only imagine the difficulty in finding new drums for it. Let alone good used ones.

[fordman]

that info is probably all correct. and it kind of confirms what i was thinking about drum brakes being larger in the drum size and the shoe for it. i wouldn't get ahead of myself yet. i think i would measure your disc first and see if it is considered hd or not. your truck is almost a f350 so things can change as i've noticed with your trucks weight rating.

[Hawkrod]

I ave not checked the 68-72's but the 73-79 have three different front discs depending on load capacity and there are two different spindle sizes on front disc brakes. I will bet that there are two for the 68-72 as well. Hawkrod

[FLATBEDFORD]

My F350 DRW has 12x3 drums front and rear. Those are some monster drums. They are $149 at Rock Auto.

[robroy]

Hey Hawkrod! It makes sense that there could be two options, yet in the factory option papers I see only one. And I have a hunch that I'd have heard of two different disc brake sizes from reading all the drum-to-disc conversion articles, but who knows!

Thanks Hawkrod!
-Robroy

[Hawkrod]

I just went and looked it up for you. It is actually quite confusing as there are 6 different spindles used on 71/2 F250 2 wheel drive trucks based on capacity but when I look up rotors it only lists one and says 3000 pound axle. I assume that means they all used the same rotor but the spindles varied (I noted two king pin sizes) with axle rating. I did note two different drums for the 68-72 F250 2 wheel drive fronts. Hawkrod

[robroy]

Hi Hawkrod, thank you! Where did you gather that info?

Thanks again,
-Robroy

[Hawkrod]

Ford Truck Master Parts Catalog. Hawkrod

[robroy]

Okay thanks! Do you have a hard copy of that or is it online somewhere?

-Robroy