Finned drums

[SIPLOWGUY]

I recently bought a 1969 Fury III. It's the first 1969 I've owned. I was a little surprised it had non-finned front brake drums. I was a little more surprised the LF drum DID NOT have reversed thread studs. the LR axle DOES have reversed threads. It became apparent to me the LF drum was replaced at one point. However, I thought starting with the 15" wheels in 1969 the drums were finned with the recessed hub. I once had a 1968 Fury III and the RF drum was finned. I was quite surprised when I popped off the wheel cover, and the studs were only 1/2 way into the lug nuts! I quickly fixed that! My 1971 Fury I had finned drums, so I assumed they started in 1969. My point here is, according to the Dealership Data Book on page 20 it shows the Fury comes with finned drums. My car DOES NOT have them. The parts catalog shows my size brake shoes DO NOT have finned drums and only lists a finned drum for the RF. Very odd, unless the hub had to be swapped. The non-finned drum shows left and right numbers. What does everyone think?

 

[MoPar~Man]

Your left (driver's side) front studs are right-hand thread, yes that means the studs were changed. Can you separate (remove) that drum from the hub? I think normally if the front studs have been changed it will mean that the drums will now be (relatively) easily removable. Or - it means someone took a right-side hub/drum and put it on your car's left side as a replacement.

Your drums are all 11-inch inside diameter, yes?

what is the width of the rear shoes? Is it 2 or 2.5 inches? I assume your front shoes are 2.75 inches wide.

 

[SIPLOWGUY]

The studs are still swedged so the drum does not slide off. The front brakes are 11 X 2&3/4, the rears are 11 X 2. The rear drums look to have fins. My 1966 Chevrolet front drums do. It's interesting that Chevrolet did that when all the other GM lines did not. I'm thinking a used drum was put on. I might change the LR studs to keep it uniform. When I needed a drum for the 68, a guy was parting out a 66 Fury that had a blown engine. He had Just done the front brakes, and the drums were freshly cut. I took EVERYTHING right down to the backing plates and used it on my 68. lol That was the late 80's and that 66 was considered "not worth fixing".

 

[MoPar~Man]

From what I've seen on Rockauto in terms of rear drums, they list a small variety of 2-inch drums that are 1969 and up, which have different P/N as the 2-inch drums for 1968 and down. I think one difference is that 1969 and up have fins. I have found that the finned drums still mount fine on my 1967, but there is one possible issue:

That's a new Raybestos 2" rear drum, but note the raised lip or edge on the center hole. You can tell me if your finned drums have the same lip. The non-finned drums are flat, no lip.

Regarding your front drums, I wouldn't change the studs. I de-swedged my hubs and drums and pressed in all new studs - right-hand thread for both sides. I can now remove and replace the front drums easily without messing with the hub.

 

[SIPLOWGUY]

From what I've seen on Rockauto in terms of rear drums, they list a small variety of 2-inch drums that are 1969 and up, which have different P/N as the 2-inch drums for 1968 and down. I think one difference is that 1969 and up have fins. I have found that the finned drums still mount fine on my 1967, but there is one possible issue:

That's a new Raybestos 2" rear drum, but note the raised lip or edge on the center hole. You can tell me if your finned drums have the same lip. The non-finned drums are flat, no lip.

Regarding your front drums, I wouldn't change the studs. I de-swedged my hubs and drums and pressed in all new studs - right-hand thread for both sides. I can now remove and replace the front drums easily without messing with the hub.

I don't have the lip on my drums. I don't plan to replace the studs on the front. The rear has the left hand studs. Those are the ones I want to change to right hand thread.