Finding the "good" wheel cylinder kits...

[rustystud]

I do hate to hear that. I'm sure you are
correct but I like drum brakes.

I'm a big fan of drum brakes, especially on trucks. They can take more damage from rocks and debris than disc brakes can. A small pebble can disable a disc brake caliper !
The sad reality is that disc brakes are cheaper to make and have greater stopping power without brake fade then drum brakes. So every manufacture has gone to them now. Even the big boy "over the road" semi-trucks have gone to "air powered disc brakes" . Really cool to see and easy to work on, but sad it's to see the drum brakes go.

 

[HDN]

I don't think disc brakes stand up to sitting idle for extended periods, especially outside. My 2012 Chrysler 200 sat out about 6 months of driving and the brakes froze up. The front ones freed up but I had to at least replace the rear calipers, and it took a bit of braking to clean the rust off the front discs.

So if you're like me where your truck sits for about 1/2 of the year due to road salt, I don't think disc brakes are going to last long.

I wouldn't mind a full air brake conversion though!

 

[rustystud]

I don't think disc brakes stand up to sitting idle for extended periods, especially outside. My 2012 Chrysler 200 sat out about 6 months of driving and the brakes froze up. The front ones freed up but I had to at least replace the rear calipers, and it took a bit of braking to clean the rust off the front discs.

So if you're like me where your truck sits for about 1/2 of the year due to road salt, I don't think disc brakes are going to last long.

I wouldn't mind a full air brake conversion though!

Yeah, disc brakes have their problems too. Still won't change the minds of the manufactures.

 

[18operator]

I just changed pads and rotors on a 2018 Mazda CX5 with 15K miles on it. It gets driven maybe twice a week, once a month in the winter. The rotors were so rusted up they just acted like sandpaper on the pads. The pads were worn down to nothing! But yet my Deuce sits in the winter with drums and no rust in there. And both vehicles are garaged!

 

[Gypsyman]

I now have two of the Dorman 3577 kits coming in for inspection. If the Dorman kits are of good quality they should be a viable option. They cost less and include the pistons. Fingers crossed. I'll report back when the Dorman kit arrives.

As promised here is the update on the Dorman 3577 kits. While I knew that they didn't include the boots they do include the pistons. Unfortunately what arrived doesn't match the photos. They have the bad springs and unmarked Made in China cups. Add this to your notes and don't be fooled by the pictures shown online. The pistons might be nice to have as spares but most likely I will be returning the kits.

Below is the picture being used by vendors and what I actually received.

 

[18operator]

That drives me nuts when vendors pull crap like that! More and more of them are doing it.

 

[Gypsyman]

It's too bad really. Made in China or not I've always had great luck with the quality of the Dorman brand products.

 

[GopherHill]

Perhaps we can make our own from beer bottle caps. Joking aside, people on this site are quite resourceful.

 

[rustystud]

That drives me nuts when vendors pull crap like that! More and more of them are doing it.

Totally agree ! False advertising should not be tolerated, especially in Automotive Brake Parts ! That could mean life or death if you have a failure.

 

[ckid]

Thanks for the updates @Gypsyman. Quality parts are definitely getting harder to find. National Parts Supply is showing out of stock now, so...

I'm nowhere near mechanically inclined enough to create my own. But with all the creative folks on this forum, it'd be cool if someone did it.

 

[kenn]

I know it is more expensive, but I have found a few places that supposedly have the oem surplus whole assembly in stock. I know it is more expensive to go that route but I have to replace at least two wheel cylinders, possibly more, and I'd rather spend more and get the complete OEM assembly. Correct me if I'm wrong, but the part number 7348976 fits both front and rear wheels correct? Equipment Parts Sales has "NOS" listed but I'm concerned about the rust and rubber caps being dry-rotted and/or brittle.

 

[ckid]

The front and rear are the same. It's certainly worth the cost to have the correct springs I would think. Good point about the condition of NOS rubber. Most of the rubber on other NOS items I have has been pretty good though.

 

[HDN]

Totally agree ! False advertising should not be tolerated, especially in Automotive Brake Parts ! That could mean life or death if you have a failure.

If a crash happens because of it Dorman better have deep enough pockets for lawyers.

But with all the creative folks on this forum, it'd be cool if someone did it.

Brake cylinder boots aren't load-bearing, right? One could make a mold and cast reproduction ones out of an appropriate rubber.

As for the brake cylinders, they can be reverse-engineered and milled out in a machine shop, or perhaps a metal 3D printer can make print-on-demand runs for them. I talked to an unobtanium metal 3D printer who said they could at least print master cylinders for old cars. I'm not sure if the technology is there to print wheel cylinders that can operate without blowing up.

 

[ckid]

@HDN, seems the biggest issue is the proper springs and the metal inserts that keep the rubber cups spread properly. The metal probably could be printed. Shouldn't be under much pressure. The springs though.... I'm not sure.

 

[HDN]

@HDN, seems the biggest issue is the proper springs and the metal inserts that keep the rubber cups spread properly. The metal probably could be printed. Shouldn't be under much pressure. The springs though.... I'm not sure.

I'm not familiar with brake system design for any kind of brakes, but I know that hydraulic systems can be under some high pressures sometimes, like thousands of psi. I'm hoping there's someone here who's more knowledgeable about that who can chime in.

I'd think off-the-shelf springs of the right size could be found with the right tension and cut to length to hold the seals in place. Admittedly I've never taken apart a brake cylinder so I don't understand how a spring holds the seals in place.

 

[rustystud]

I'm not familiar with brake system design for any kind of brakes, but I know that hydraulic systems can be under some high pressures sometimes, like thousands of psi. I'm hoping there's someone here who's more knowledgeable about that who can chime in.

I'd think off-the-shelf springs of the right size could be found with the right tension and cut to length to hold the seals in place. Admittedly I've never taken apart a brake cylinder so I don't understand how a spring holds the seals in place.

The average drum brake system has a pressure of 800 PSI in the 1/4" to 5/16" lines. Now multiply that by the surface area of the piston and you will get the pressure the housing needs to hold. Then you need to factor in a safe working pressure and burst pressure. Usually it is 3:1 . It's been a few decades since I had to calculate the volume of a cylinder (the brake cylinder) and multiply it by the volume of another cylinder (the brake line) to determine the amount of force against the piston. I suppose I could Google it.

 

[Gypsyman]

I received the Napa UP 4419 wheel cylinders today and immediately tore one down. Happy to report that they still have the good springs.

 

[ckid]

Cool. What about the metal caps that keep the rubber cups spread though? Are they included? Curious because all of the cylinders on my truck when I got were the crappy springs with no metal caps. Anywhere to source those?

 

[Gypsyman]

With the "good" springs the ends are formed to match the taper of the cups and act as a built in spreader so no separate metal spreader is required. As far as availability of the metal cup spreaders as a stand alone item, I don't know. Hopefully one of the experts on these will chime in with that answer.

 

[GopherHill]

Cool. What about the metal caps that keep the rubber cups spread though? Are they included? Curious because all of the cylinders on my truck when I got were the crappy springs with no metal caps. Anywhere to source those?

The springs with the formed ends will work quite well. The metal end caps may be just a memory.