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Thanks Bob, the KYB 344066 looks much better than the 343127. I wish I would've known that earlier. Since I already have the 343127 I may just see how they do with longer bolts and thick washers. Worst case scenario they don't work and swap them out.

Riki - I considered welding, and I may still do that. I can probably just weld on the thick washers I already have and use it that way. Kind of janky though.

I have changed the mounts put soap on the rubber and twist and pull out soaking on warm water will also help. Washers also work longer square carriage bolts are easy to find if needed

Made some progress tonight. Finally was able to get the rear shocks replaced. Getting the first one of wasn't too bad, just lots of stuff in the way. When I did the rear shocks on my '54 it had no fuel tank or exhaust, so I had nothing but space. Much more crowded under a '56. The second upper shock nut was the devil's work. But I prevailed and finally got it out.



Car is nice and quiet now, and the TL so far seems to work way better. The old shocks that I took out would compress, but never return to extension. They would just stay down. I wonder if the TL was having to fight that?

Finally got the driver's rear drum off. It was seized on the hub and lug bolts. I cleaned up those mounting surfaces, and applied a very light layer of anti seize to the interference spots. The drum surface looked good, as did everything inside. Shoes look new. Reinstalled and readjusted the brakes.



The passenger rear drum came off without a problem. Everything looked good in here, until I looked under the cylinder boots. One side is nice and wet, so I'll be needing to replace the cylinder.



Also compared the cheapo paint markers to the Forney. The paint on the Forney is a little more consistent, but the cheap marker is easier to get straight lines because the tip is smaller. I can rest it against the fold in the metal and use that as a guide. I takes yet strokes per line though, one for the top edge and one for the bottom edge. I'm not done with this panel, but it does look much better so far.



Next up is clear coating the emblems and reinstalling. Then figure out where the leaks are coming from in the master cylinder.

Did you check the fit of the shoes to the drums?
While the passenger side cylinder was wet, was the driver side cylinder clean and dry?
Did you check the cylinder size?

Back on the subject of front shocks, KYB does not sell the lower mounts alone so you can’t change the ones you have. KYB also says that the warranty is only good if the shock is used for an application they have on their list. I haven’t heard what it takes to add to their list.

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I did not pull any shoes off yet. All the wear seems to be even across the surfaces of all shoes.

Passenger rear cylinder was the only wet one. All others were dry. I didn't measure cylinder size, but the rears are smaller than the fronts as they should be.

I'll probably tack weld the fender washers to the front shocks as extra security. I don't really anticipate any problems but it won't hurt to add a little extra strength.

Going to get back to the 400 this weekend. I had to move it out of the shop to make room for another project that took most of the weekend. But that project is done, the shop has been put back together, and the 400 is ready to go back on the lift. It was an exciting time compressing very heavy springs, tight spaces, and heavy tires.










A couple of things have come up on the 400:
1.) The under seat heater does seem to be leaking after all. I've noticed a musty smell in the car, and after warming the engine up I found the carpet on the passenger side to be slightly damp. Not sopping wet like it was before, but noticeably damp. The under seat heater is the only thing it could be. So it looks like that core will be coming out when I pull the radiator.

2.) Speaking of the radiator, the pin hole leak on the front is spraying coolant everywhere when the engine is warm. I really can't drive it until I get the radiator fixed. So that has now moved to the top of the list.

3.) I picked up a replacement wheel cylinder for the leaking passenger rear, only to find that the sizes are indeed different. The one I bought was pulled from the parts cross reference here, and is the correct 1" bore. The cylinder on the car is much bigger. So now I'll need to check all the other cylinders to see what size they are. For sure both of the rears are oversized and both will need to be replaced. Not sure on the front yet. I wonder if this might be part of the subpar braking I've experienced?

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Most likely.

With the single circuit hydraulic system the pressure will be the same at each wheel cylinder, but force on the brake shoes is determined by the cylinder size. Also larger cylinders consume more fluid during operation resulting in greater brake pedal travel.

Your larger rear cylinders also result in increased rear brake bias.
You want more braking to occur at the front because more of the car's weight acts on the front tires during braking.
Can't wait to hear what the size other cylinders are.

IDK where you are buying them but you can get a full set on RA for $32...

https://www.rockauto.com/en/catalog/packard,1956,four-hundred,6.1l+374cid+v8,1440836,brake+&+wheel+hub,wheel+cylinder,1952

Just FYI... this is where MM gets theirs as well.

Thanks Bob and William. I bought the replacement cylinder at Napa ($20) because it was close and I thought I'd just be replacing the one leaking cylinder. Once I compared the two I realized they were quite different. So I went ahead and bought replacements for the other 3 on RockAuto. I know for sure the other rear is too big. I'll need to check the fronts and see, but I may just replace all of them anyways.

Larger cylinders will exert more force, correct? Makes sense that the pedal travel would be more.

Yes but there is a proportion of master cylinder volume and wheel cylinder effective area that needs to be maintained so that the master cylinder has enough fluid to extend the wheel cylinders, yet they can back off sufficiently when the brake is released.

Though, since the brake springs pull the cylinders "in" when brake pressure is off, I don't think you could easily get past the baseline "off" position in the wheels, so there would never really be enough fluid in the master to extend them all.