On an F4, does the bigger (longer surface area) shoe go toward the front or the rear of the backing plate? I asked this question in a thread of another topic and got an answer (thanks!), but I have found several conflicting answers for both ways when I did a search.
I have my F4 nearly ready to put the rims on and want to get this right first. My truck had the longer shoe toward the front when I took it apart, and that's how I put it back together.

 

I've been wrong before. I'm looking at my Ford literature now.

 

Self-energizing brakes use the smaller shoe to the front. I don't know why your truck would not be that type, but I can't figure out how the two shoes are connected at the bottom. Is it an anchor, or does it transfer force from the primary (front) shoe to the bottom of the rear shoe? Read here, quite a ways down the page at "Drum Brake Operation"
Brake Fundamentals Training Manual | Wingate Motors

 

Cool. Here are the numbers from the HiPo catalog, they do agree with a post from NumberDummy.

2) 91T-2018-C .. Rear Primary Brake Shoe & Lining.

2) 92Y-2018-C .. Front Primary Brake Shoe & Lining.

2) 91T-2019-C .. Rear Secondary Shoe & Lining.

2) 92Y-2019-C .. Front Secondary Shoe & Lining.

Now, the double anchor brake system uses the primary shoe on front per page 221 of the 54-55 shop manual (sorry, that's the only one I currently have). The illustration does show the primary shoe to be BIGGER than the secondary shoe. The picture could be wrong. Maybe somebody has a pair handy and can compare part numbers to see which is actually longer.
My opinion? If it's working correctly, it just may be right. Mixing the shoes typically causes noticeable problems such as brake grab or locking. Horror!

 

So at the bottom, both shoes are anchored? If so, the front shoe, if bigger, would be doing 75% of the braking and would have more lining so it wears out at the same rate as the rear shoe.

Raytasch has an F-4, you might PM him. So does Jolly Roger Joe

 

Brake shoes are like rabbits . Short legs in the front ! That is what I learned years ago ! The shorter shoe goes to the front , longer to the rear . Just like a rabbit , long legs are in the rear !

 

Usually, but these don't appear to be regular "rabbits"!

 

I saw somewhere that the shorter shoe goes toward the front, but something about the front brakes confuses me. My F-250 front wheel cylinders have one piston pointing toward the front. I just don't see how that effectively uses both shoes. Anyone know? The rear cylinders have pistons pushing both front and back.....

Jeremy mentioned on my thread a while ago. BoB (Big on Back)

 

As does JollyRogerJoe. The double anchor brakes are a different breed. A '48 F4 is a catalog model code "TL" and shows to have come with double anchor brakes - as, apparently, did most of them from the monkey face era.

 

Is this a lockheed type brake system ? Single wheel cyl .or dual per side ? Fixed ,pinned anchors ? The leading shoe is usally the small shoe . Unless an inverted system , lockheed , or lucas system is used . I have seen different styles used , just asking .

 

Doop ! Bendix !

 

I believe the brakes on mine are double anchor, as both shoes are anchored at the bottom. I don't know which way is correct, just that the longer shoe was on the front when I removed the drums from both the front and rear. I haven't had the truck long enough to experience it with working brakes (I'm working up to it though!), so I can't speak for how well it was stopping before it went into storage decades ago before I dragged it home.

I have the truck on blocks now during the brake rebuild and want to get this right before I get it all back together. I thought all was correct until I read something about the shoe orientation in another post and started to question id mine was correct or not.

 

Self energising drum brakes . They work well

 

Thanks for all the help and thoughts on this subject. I had scanned the manual last night but could not find anything definitive on the shoe orientation, but I did this morning. I had to look even further into the brake section, page 233.

 

No, these aren't. On typical self-energizing brakes, the front shoe tips in and helps energize the secondary by pushing the bottom end of the secondary -- the bottoms of the shoes are NOT anchored. On these brakes only the front shoe is self-energizing, it cannot transfer any force to the secondary.

My bet is that the long shoe does go to the front, so that wear is equalized. Also the same force is applied to the two shoes by the wheel cylinder, so the pressure on the rear shoe's lining is higher (same force over a smaller area), and braking force is proportional to the pressure applied.

But I'd sure like to see this confirmed!