Which booster is right for my F250 w/disc (8,100lb GVW)?

[robroy]

Good evening,

I'm interested in replacing the power brake booster on my 1972 F250. It has disc brakes and the 8,100lb GVW rating, which means some parts are shared with the F350 (like springs, and maybe brakes).

I've looked through the Autozone and Rockauto online catalogs for a booster for my truck and have found none. They only seem to have boosters for F250's with four wheel drums brakes.

Here's a photo of the booster they have listed for the '72 F250 with four wheel drum brakes. It's an A-1 CARDONE #5473515.



And here's a photo of the booster they have listed for a '72 F350 with disc brakes. It's an A-1 CARDONE #5473112.



When I first bought my truck it had a booster installed that looked more like the larger one (listed for the F350). It leaked, and at some point through the years I replaced with with one that looked exactly like the smaller one (listed for the F250). I think an auto parts guy convinced me that it was the right one at the time.

Which booster's correct for my truck?

Also, could anybody guess at what symptoms my brakes could have if the wrong one were installed?

Thanks very much!
-Robroy

[fordman]

the difference in the booster size is one is a dual diaphram and the other is a single diaprham. i think the smaller one is a dual and the single is the larger one. your truck would probably be alright with the smaller one. the f250 i just parted out had the smaller dual type on it. but so does my 68 f100. i am unsure about stopping power o resae of pedal with either size. i think the dual diaphram one has the ease of pedal when pushing the brake. i think.

[robroy]

Hey Fordman, thanks for your reply!

In additional to whatever other differences there may be between the boosters, I notice that the push rod leading to the brake pedal is longer on the larger booster.

Is there actually a difference in the length between the brake pedal and the booster on different Bumpside trucks? I'd be surprised, unless the brackets holding the booster to the firewall are also different.

Thanks again Fordman,
-Robroy

[fordman]

67 is different when it comes to rod length. i think the 67 is shorter. the 68-72 are the same they just look longer.

[390F100]

Check out www.mbmbrakes.com

this is where I bought the booster/master/bracket assy for my 68 F100 and it was a perfect fit and looks great too, and for 200.00 it was well worth it.

[robroy]

Hey 390F100, thanks for that tip!

That looks like a good site with quality products.

Did you order universal parts and adapt them to your truck? Or do they make anything specific for our trucks?

And why did you choose to go this route instead of buying auto parts store replacement parts?

Thanks again!
-Robroy

[robroy]

Is anybody else willing to bet on which booster's the right one for my heavy F250?

I'm inclined to try the larger booster that's sold for the '350, because most of the other front end parts seem to be shared with it on my truck.

Thanks!
-Robroy

[robroy]

Does anybody else here have heavy F250 or '350s? Which booster does your truck have? Thank you!

[fordman]

now that i seent he 8100 thing i do remember willow or hawk saying something abotu the f350 booster being the one to use for another truck similar to yours. so it might be ok to us the f350 booster. i think they were going to take one off of a dentside f350 and use it because thats all the choice they had

[robroy]

Hi Fordman! Thank you for the tip; I'll PM Willow' and Hawk' to see if they remember anything about this.

And thanks for answering so many of my questions over the past months!

-Robroy

[willowbilly3]

Hi. I don't have a rock solid answer but here is my experience. My 69 drum brake F250 had the booster that was so big it required an offset mount to clear the engine. I pulled another smaller booster from a junk pickup and installed it. I also got a new master cylinder but not sure now if I replaced them at the same time. Anyway my brakes work fine and I don't think the parts store ask me what master cylinder I had other than power brakes. My best guess is those will interchange if you have the correct Mounting bracket. I am pretty sure the F350 and F250 use the same pedal assembly so there shouldn't be a problem there.

[robroy]

Hi Willowbilly3, thanks very much for responding!

If the large booster you experienced on your drum brake truck is the same as the large booster here, it doesn't like something I'll want to stay away from. Unless there's some great benefit of converting to it.

Thanks again!
-Robroy

[robroy]

So the larger booster arrived and I got some side by side photos comparing it to my previous, smaller booster.




Fordman, you were right about the rod length being the same! Thanks.

And it looks like it'll be a direct bolt up. I'm pretty sure this is what my truck had on it when I bought it, and probably what it had from the factory. So I'll give the big booster a whirl!

Thanks!
-Robroy

[fordman]

that new booster looks very similar to the booster on my 68 f100. i have never seen a booster as small as the blue one on any truck i have ever parted out.

[robroy]

No wonder the brakes never worked very well!